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120V vs 240V Heat Pump Water Heaters
Compare 120V and 240V heat-pump water heaters by circuit, recovery, first-hour rating, backup heat, efficiency, and retrofit cost.
Electric2029 Water Heater Standards: What Changes
The 2029 federal standards affect newly made water heaters, not your installed tank. See what changes for electric, gas, and tankless models.
Troubleshooting5 Flashes on Water Heater: What It Means
Five flashes is a brand-specific code — usually the upper element on electric, or a gas-valve/false-pilot fault. Decode it before you reset.
TroubleshootingAERCO Water Heater Troubleshooting
AERCO Innovation or SmartPlate not making hot water? Lockouts usually trace to condensate, flow, ignition, or scale. Safe checks before calling a pro.
RVAirstream Water Heater Troubleshooting
Airstream coaches use Atwood/Dometic, Truma, or Suburban heaters. Identify the unit behind the exterior door, then follow the right checks.
TanklessAirthereal Tankless Troubleshooting
An Airthereal electric tankless running cold usually means no 240 V, low flow, a clogged inlet screen, or an E1–E4 code. What each code means.
RVAlde RV Water Heater Problems
Alde no-heat is glycol, 12 V, mixing valve, or a lockout — not an Atwood tank. Photograph the panel.
RVAlde Water Heater Not Working: RV Fixes
Alde Compact hot water failures come from 12 V power, low or air-locked glycol, LP supply, pump, or a panel lockout. How to narrow it safely.
ElectricAlpha Water Heater Red Light Blinking
Record the Alpha model and exact red-light pattern. Keep electrical covers closed and use model-specific instructions to interpret a fault.
GasAmerican Water Heater Pilot Won't Stay Lit
An American standing-pilot that dies is a thermocouple, FVIR, or gas valve. If you smell gas, leave.
TroubleshootingAmerican Water Heater Troubleshooting
American water heaters share A. O. Smith hardware. Diagnose a cold, blinking, or leaking unit by reading the LED count and finding the wet part.
TroubleshootingAmtrol BoilerMate Indirect Problems
BoilerMate no-heat is the aquastat, circulator, or scaled coil — not a dead boiler. A wet jacket is replacement.
TroubleshootingAO Smith Blinking Green Light Codes
A slow green blink on an A. O. Smith gas valve is often normal. Two or more flashes is a fault code. How to count the pattern and read it.
TroubleshootingAO Smith Blinking White Light
A white or pale LED blinking on an A. O. Smith gas valve can be normal, a call for heat, or a lockout. How to tell them apart from the count.
ElectricAO Smith E02 Code: High-Limit Trip
E02 on an A. O. Smith Energy Smart electric tank is a high-limit (ECO) trip. Why it happens, when one reset is reasonable, and when it isn't.
ElectricAO Smith E55 Code: Leak Detected
E55 on an A. O. Smith Energy Smart tank means the leak sensor found water. Shut off power, find the wet part, and learn when the tank is done.
GasAO Smith Gas Control Valve Problems
A. O. Smith gas control faults usually come from a weak thermocouple or thermopile, an LED lockout, a clogged FVIR screen, or a failed valve.
GasAO Smith Gas Water Heater Reset Keeps Tripping
An AO Smith gas reset that trips again points to venting, flame, or a failing control. Stop resetting.
ElectricAO Smith Hybrid Problems: Codes
A. O. Smith Voltex hybrid not heating? Common causes are a dirty filter, vacation mode, an element or ECO fault, a compressor code, or a leak.
GasAO Smith Igniter Not Working
An A. O. Smith that won't light often has a hot-surface igniter that never glows, a control lockout, or no 120 V. How to narrow it down.
TroubleshootingAO Smith Leaking From the Bottom
Water under an A. O. Smith can come from the drain valve, T&P discharge, a fitting, an element gasket, or the tank. How to find the source.
TanklessAO Smith Tankless Reset Button
Most A. O. Smith tankless units reset by cycling 120 V power, not a hidden button. When one reset is safe, and when a code or gas smell means stop.
TanklessAO Smith Tankless Water Heater Troubleshooting
An AO Smith tankless that is cold needs a code, flow, power, gas, or vent check. Photograph the display.
TanklessAO Smith Tankless With No Hot Water
An A. O. Smith tankless with no hot water usually has no 120 V, no flow signal, a lockout code, or no gas. Read the display before resetting.
TroubleshootingAO Smith Water Heater Blinks 3 Times
Three flashes on an A. O. Smith means different faults on electric, power-vent, and atmospheric models: thermistor, pressure switch, or other.
TroubleshootingAO Smith Water Heater Humming Noise
An A. O. Smith humming can be a transformer, element, gas valve solenoid, or hybrid compressor. Match the sound to when it happens.
TroubleshootingAO Smith Water Heater Troubleshooting
A. O. Smith troubleshooting by product: gas, power-vent, Energy Smart electric, Voltex hybrid, or tankless. Identify yours, then follow its checks.
TroubleshootingApartment Water Heater Not Hot Enough
Lukewarm apartment water is a mixing valve, crossover, dead element, or building recirc — not a bigger tank.
TroubleshootingApartment Water Heater Not Working
Apartment water heater not working or leaking? How to make it safe, what to report to your landlord, and which repairs to leave to them.
TroubleshootingApollo Water Heater Troubleshooting
Apollo can mean a HydroHeat coil system, a mixing valve, or a compact electric tank. Identify the product from the plate before troubleshooting.
RVAqua-Hot Water Heater Problems
Aqua-Hot no-heat faults usually come from power, diesel, boiler fluid, or circulation. Check the display.
TanklessAquah Water Heater Troubleshooting
An Aquah tankless that stays cold usually has a power, flow, LP, clogged screen, or E-code problem. Safe checks for electric and propane units.
TroubleshootingAriston Leaking From the Bottom
Water under an Ariston Andris, Velis, or Pro1 can come from the drain, T&P, a bottom fitting, or the tank itself. How to find the wet part.
TroubleshootingAriston Leaking From the Front Panel
Water at an Ariston front cover comes from behind it: an element gasket, thermostat pocket, or the tank. How to tell a gasket from a failed tank.
TroubleshootingAriston Pressure Relief Valve Leaking
An Ariston T&P valve that drips is reacting to pressure or temperature, often thermal expansion. Why it happens and why it must never be capped.
ElectricAriston Water Heater Reset Button
The Ariston reset is a high-limit (ECO) behind the front cover. How to press it safely on a full tank, and what a repeat trip means.
TroubleshootingAriston Water Heater Troubleshooting
An Ariston that is cold, leaking, or showing a fault needs a power, flow, sensor, or tank check. Photograph it.
TroubleshootingAriston Water Heater With No Hot Water
A cold Ariston usually has no power, a tripped ECO, a failed element, or a thermostat fault. Checks for Andris, Velis, Pro1, and tankless models.
TanklessAtmor Tankless Water Heater Troubleshooting
An Atmor tankless passing cold water usually has no 240 V, too little flow, a clogged screen, reversed lines, or too little kW for the fixture.
RVAtwood Clicking But Not Lighting
Atwood/Dometic click with no flame is spark without LP, a dead ECO, or a failed solenoid. Test spark with gas off.
RVAtwood Electric Water Heater Not Working
Atwood/Dometic electric heat dies from a tripped ECO, bypass valve, dead element, or no 120V. Reset safely.
RVAtwood RV Water Heater Troubleshooting
Atwood/Dometic RV water heater not working? Split the problem into gas, electric, ECO, or bypass, then follow the matching checks.
RVAtwood Water Heater Reset Button Location
The Atwood/Dometic reset is the ECO behind the exterior door. Where to find it, how to press it safely, and why a thermal fuse isn't a reset.
RVAtwood Water Heater Will Not Stay Lit
An Atwood/Dometic that lights and then dies is losing flame: low LP, a dirty sense electrode, an ECO trip, or an open thermal fuse.
TanklessBaxi Tankless Troubleshooting: Codes & Lockouts
Baxi combi cold showers often trace to ignition (E133), low pressure (E118/E119), circulation, fan, diverter, or a scaled plate exchanger.
TanklessBosch AquaStar Tankless Troubleshooting
Bosch AquaStar tankless running cold? Causes include low flow, a clogged inlet screen, pilot or igniter faults, a flue limiter, or gas pressure.
ElectricBosch Powerstar Tankless Troubleshooting
A Bosch Powerstar tankless not heating may have a dead 240 V leg, low flow, a stuck flow sensor, a tripped thermal cutout, or reversed lines.
TroubleshootingBosch Water Heater Troubleshooting
Bosch troubleshooting for Therm and Greentherm tankless, AquaStar, Powerstar electric, and Tronic mini-tanks. Codes, flow, power, and leaks.
ElectricBradford White Electric Not Heating Up
A Bradford White electric not heating usually has a tripped breaker, a popped ECO, a failed upper element, or a bad thermostat. How to narrow it.
TroubleshootingBradford White Leaking From the Bottom
Water under a Bradford White can come from the drain valve, T&P discharge, a fitting, an element gasket, or the tank. How to find the source.
TroubleshootingBradford White Leaking From the Top
A leak at the top of a Bradford White is usually the T&P, anode, a nipple, heat trap, or connector, not the tank. How to find the wet fitting.
TroubleshootingBradford White No Status Light
A dark Bradford White status light can mean the control is off, a dead thermopile, a failed ICON, or no 120 V on power-vent models.
TroubleshootingBradford White Not Hot Enough
Lukewarm Bradford White water is a dip tube, lower element, mixing valve, or setpoint — not “buy a bigger tank.” Diagnose it in order.
GasBradford White Pilot Light Reset
How to relight a Bradford White ICON correctly: wait for the status LED to go dark, then one lighting cycle. What to do if it won't hold.
GasBradford White Pilot Won't Light
A Bradford White pilot that never lights usually has a closed gas cock, empty LP, a dead piezo, a clogged orifice, or an ICON still in shutdown.
TroubleshootingBradford White Water Heater Beeping
ICON gas tanks don't beep. A beeping Bradford White is usually an Infiniti tankless, AeroTherm hybrid, power-vent board, or a leak sensor.
GasBradford White Water Heater Igniter Not Working
A Bradford White igniter that will not glow or spark can be power, wiring, the igniter, or control. Stop repeated starts.
ElectricBradford White Water Heater Leaking From Thermostat
Water at a Bradford White thermostat can be a tank leak, element gasket, or fitting above it. Shut energy down.
TroubleshootingBradford White Water Heater Troubleshooting
Bradford White troubleshooting for ICON gas, electric, Infiniti tankless, and AeroTherm hybrid models. Read the LED, then follow the checks.
GasBradford White Weak Pilot Signal (2 Flashes)
Two flashes on a Bradford White ICON means a weak pilot signal: the thermopile isn't making enough millivolts. Causes and next steps.
TroubleshootingBrand New Water Heater Has No Hot Water
A brand-new tank with no hot water is usually an install issue: closed valves, an unfilled tank, power or gas off, or a misplaced dip tube.
TroubleshootingBrand New Water Heater Only Runs Warm
A new water heater that only runs lukewarm is usually a mixing valve, misplaced dip tube, unwired element, or vacation setting. How to check.
TroubleshootingBrand-New Water Heater Making a Popping Noise
Day-one popping is air, pipe expansion, delayed ignition, or debris — not a 12-year tank. Name the sound.
RVBroken RV Water Heater Sight Glass
A cracked Suburban or Atwood sight window can dump LP into the bay. Shut the bottles. Do not spark it.
TroubleshootingBuderus Indirect Water Heater Problems
Buderus Logalux no-heat is usually the sensor, DHW pump, or boiler priority — not a dead tank. Leak from the vessel means replacement.
TanklessCamplux Water Heater Not Lighting
A Camplux that won't light usually has dead batteries, empty LP, too little water flow, a wet electrode, or a tripped overheat or ODS sensor.
TanklessCamplux Water Heater Troubleshooting
Camplux tankless running cold? Common causes are empty LP, dead batteries, low flow, a tripped ODS, a clogged inlet, or an E1/E2 code.
TroubleshootingCan You Use Water If the Water Heater Is Leaking?
You can keep cold water on if you close the heater's cold inlet, but running hot water through a leaking tank empties it. What to do first.
GasCarbon Monoxide From the Water Heater
A CO alarm near a gas water heater can mean a blocked vent, backdrafting, a failed power-vent blower, or overfiring. What to do right away.
ElectricChanging a Water Heater Thermostat
A thermostat replacement needs diagnosis and the correct part. Prepare useful observations and leave internal electrical work to a qualified technician.
TroubleshootingCold Water Inlet Leaking on the Heater
A leak at the cold water inlet is usually a dielectric nipple, heat trap, connector, or Hydrojet adapter, not the tank. How to find it.
GasControl Box Leaking Gas? Get Out Now
A gas smell at a water heater control valve is an emergency. Leave the building and call the gas utility from outside. What not to do.
GasDefender Pilot Light Will Not Stay Lit
A Bradford White Defender pilot that goes out usually has a weak thermopile, a lint-clogged FVIR screen, a draft, or a failed ICON control.
RVDometic Water Heater Thermal Fuse Blown
An Atwood/Dometic thermal fuse opens from flame rollout, a blocked flue, or overheating. Find the cause before replacing it; never jumper it.
GasDon't Match-Light an Electronic-Pilot Heater
Electronic-ignition water heaters should never be lit with a match; it risks delayed ignition. How to tell your ignition type and what to do.
GasDon't Purge a Water Heater Gas Line Yourself
Do not open gas fittings to release air. Learn what to do after a failed installation start and when gas odor requires immediate evacuation.
TroubleshootingDrain a Water Heater With No Floor Drain
No floor drain? You can drain a water heater to a sink, tub, or toilet with a hose or pump. Safe steps, including shutting off power or gas first.
GasEco-Defender Water Heater Won't Turn On
A Bradford White Eco-Defender that won't fire usually has the pilot out, an ICON lockout, a tripped FVIR sensor, or a dead thermopile.
ElectricEcoSmart Tankless Water Heater Low Pressure
Low flow from an EcoSmart can be a clogged screen, closed valve, or house-side restriction. Test a tub spout.
ElectricEcoSmart Water Heater Troubleshooting
An EcoSmart tankless that is cold needs power, flow, error, or element checks. Photograph the display.
ElectricElectric Heater Dead After a Power Outage
An electric water heater cold after an outage usually has a tripped breaker, one dead leg, a tripped ECO, or surge damage. Safe checks first.
ElectricElectric Heater Leaking at the Bottom Element
Water at the lower element is usually a flange gasket or the threads, not necessarily a failed tank. How to tell the difference safely.
ElectricElectric Tankless Gets Hot, Then Cold
Distinguish electric tankless temperature cycling, capacity limits, and shutdowns. Includes a sourced flow and temperature-rise calculation.
ElectricElectric Tankless Goes Cold Mid-Shower
An electric tankless shutdown can involve power, flow, or protective controls. Record the fault and learn when to arrange professional service.
ElectricElectric Water Heater Smells Like Gas?
A gas smell near an electric water heater is still an emergency: another appliance or line may be leaking. What the smell can mean and what to do.
ElectricEnergy Smart Water Heater Troubleshooting
Energy Smart electric tank not heating? Causes include power loss, E01 dry fire, E02 high limit, element codes, or a module fault.
TroubleshootingEnvirotemp Water Heater Troubleshooting
An Envirotemp heater that is cold, leaking, or locked out needs an exact model and symptom check. Stop unsafe resets.
TanklessExcel Tankless Water Heater Troubleshooting
Excel tankless running cold? Common causes are empty LP, dead batteries, low flow, a tripped ODS, a clogged inlet, or a blocked flue.
TroubleshootingExpansion Tank Full of Water? Bladder Dead
If an expansion tank's air valve spits water, the bladder has failed, which often explains a weeping T&P valve. Why adding air won't fix it.
TroubleshootingExpansion Tank Pinhole Leak: Replace It
A pinhole leak in an expansion tank shell means the tank needs replacing. How to isolate it safely and why patches aren't a fix.
TroubleshootingFactory Plastic Drain Valve Is Dripping
A dripping plastic drain valve at the bottom of a tank is usually the valve itself, not the tank. How to confirm and what to replace it with.
TroubleshootingFlashing Green Light on a Water Heater
A flashing green light on a water heater is often normal. Two or more flashes usually means a brand-specific fault code. How to read it.
TanklessFogatti Tankless Troubleshooting
Fogatti tankless running cold? Common causes are empty LP, dead batteries, low flow, a tripped ODS, a clogged inlet, or an E1 lockout.
RVForest River Electric Water Heater Dead
Forest River coaches use Suburban or Atwood heaters. Electric mode fails from no 120 V, bypass valve position, or a tripped ECO.
RVForest River Heater Dead? Read the Door Badge
Forest River coaches use Suburban, Atwood, or tankless — not a Forest River OEM tank. Identify the door.
RVFurrion Tankless E1 Ignition Failure
Furrion tankless E1 means ignition failure: the board never proved flame. Causes include LP supply, low 12 V, spark, or the flame probe.
RVFurrion Tankless Water Heater Troubleshooting
A Furrion tankless that is cold or flashing E1 needs power, flow, gas, or ignition checks. Photograph the code.
GasGas Burner Lights Then Dies, Pilot Stays Lit
Pilot stays lit but the main burner shuts off? Causes include a weak thermopile, a failing gas valve, a rollout or ECO trip, or a clogged FVIR screen.
GasGas Burner On but Still No Hot Water
The burner is firing but the water is still cold? Suspect the dip tube, sediment, a mixing valve, a closed hot valve, or a plumbing crossover.
GasGas Hot Water Heater Power Vent Problems
A power-vent gas heater that will not start or keeps shutting down needs air, vent, blower, or pressure checks.
GasGas Smell After Water Heater Replacement
Mercaptan after a heater swap is a leak until a utility or licensed fitter says otherwise. Leave. Don’t sniff fittings.
GasGas Thermal Switch Keeps Tripping
A gas thermal switch that keeps tripping is rollout, vent, or FVIR — not a reset ritual. Stop jumpering it.
GasGas Thermal Switch Won't Reset
A thermal switch that will not click back is still hot, melted, or a blocked vent. Do not jumper it.
GasGas Valve Electronic Fault Detected
Electronic fault detected on a Bradford White ICON or Honeywell gas control is a valve electronics lockout. What the LED count means.
GasGas Water Heater Burner Not Lighting at All
A gas burner that won't light at all usually has a closed gas cock, empty LP, a control lockout, a failed igniter, or no gas supply.
GasGas Water Heater Dead After a Power Outage
A gas water heater dead after an outage may have a 120 V lockout, a failed power-vent blower, or an extinguished pilot. What to check.
GasGas Water Heater Dead After Rain?
A gas water heater that stops after rain may have a wet FVIR screen, a drowned pilot, a soaked vent, or a wet pressure switch. Safe checks first.
GasGas Water Heater Error Codes
Gas water heater codes are model-specific. Photograph the light or display, check only safe basics, and hire a licensed pro for repeats.
GasGE Water Heater Pilot Light Won't Light
A GE pilot that never lights usually has a closed gas cock, empty LP, a dead piezo, a clogged orifice, or electronic ignition with no pilot.
GasGE Water Heater Pilot Will Not Stay Lit
A GE standing pilot that goes out when you release the knob usually has a thermocouple that isn't proving flame. Other causes and safe checks.
TroubleshootingGeoSpring FF Code: EXV Out of Range
GE GeoSpring F-F (FF) means the electronic expansion valve is out of range, often a sealed-system problem. What you can check before calling a pro.
RVGirard Tankless Reset Button: Clear a Lockout
How to clear a Girard GSWH-2 lockout with a faucet or 12 V reset, when one reset is reasonable, and which codes or smells mean stop.
RVGirard Tankless Troubleshooting: Codes & Lockouts
Girard RV tankless not heating? Most cases are an E1/E2 ignition lockout, low 12 V, an ECO trip, a probe fault, or freeze mode. What each means.
RVGrand Design Heater Dead? Read the Door Badge
Grand Design coaches use Suburban, Atwood/Dometic, or tankless heaters. Identify the unit behind the door, then check bypass, ECO, LP, and 12 V.
ElectricHeat Pump Water Heater in a Garage, Closet, or Basement?
Compare garage, closet, basement, laundry-room, attic, and outdoor HPWH locations by air, temperature, drainage, noise, and service access.
ElectricHeat Pump Water Heater Sizing: 50, 65, or 80 Gallons
Size a heat-pump water heater with first-hour rating, peak demand, recovery mode, inlet temperature, and the home's actual usage.
ElectricHeat Pump Water Heater Tax Credit in 2026
The federal heat-pump water-heater credit ended in 2025. Check the rebates that may still reduce a 2026 installation cost.
TroubleshootingHeater Connector Leaking, Not the Tank
A leak at a water heater's flex connector, dielectric nipple, or union is usually the fitting, not the tank. How to identify and isolate it.
ElectricHeater Trips Breaker After a Few Minutes
A delayed breaker trip can have several electrical causes. Learn what to record, why repeated resets are unsafe, and what a technician should check.
ElectricHeating Element Stuck in the Water Heater?
A heating element that won't come out is usually seized by scale. When to stop before damaging the tank fitting and causing a leak.
GasHoneywell Thermocouple Will Not Hold the Pilot
A Honeywell gas control that won't hold the pilot may need a thermopile, not a thermocouple. How to identify the valve type before buying parts.
GasHoneywell Water Heater Igniter No Spark
No spark from a Honeywell water heater control usually means lockout, no 120 V, a cracked electrode, or a failed module. How to narrow it.
TroubleshootingHot Water Heater Smells Fishy? Split Air vs Water
A fishy smell in the air near a heater can mean overheating wiring; fishy hot water is usually water chemistry. How to tell which you have.
RVHow to Reset a Suburban RV Water Heater
Reset a Suburban ECO once with a full tank, or cycle DSI lockout after you find the cause. Repeat trips mean
TanklessHow to Reset a Takagi Tankless
Reset a Takagi once after you fix the cause — power off 10–30 seconds. Do not reset a 13 remaining-flame or a flooded burner.
TroubleshootingHow to Shut Off an Apartment Water Heater
Leaking apartment heater? Shut off cold water, then gas or the 240V breaker only if safely accessible. Notify the landlord immediately.
TroubleshootingHTP Phoenix Problems: Lockout to Leak
Phoenix lockouts are condensate, ignition, sensors, or scale — not a mystery board. Run this sequence.
TroubleshootingHTP Water Heater Troubleshooting Steps
HTP Phoenix and SuperStor failures follow a short list: ignition, condensate, sensors, scale. Run these checks.
TroubleshootingHybrid Water Heater Noise: What It Means
Hybrid noise is the compressor, fan, check valve, or a failing pump — not tank kettling. Name the sound.
TroubleshootingHydrojet Fitting Leaking, Not the Tank
A leak at a Bradford White Hydrojet fitting is usually the cold inlet nipple, dielectric, or adapter, not the tank. How to tell the difference.
RVJay Flight Heater Dead? Read the Door Badge
Jay Flight trailers use Suburban, Atwood/Dometic, or tankless heaters. Identify yours, then check the bypass, ECO, LP, 12 V, and ignition board.
TroubleshootingKenmore Water Heater Troubleshooting
Kenmore water heaters are built by A. O. Smith or Rheem. Identify the maker from the plate, then diagnose the LED, ECO, element, or leak.
RVKeystone RV Electric Water Heater Dead
Keystone RVs use Suburban or Atwood/Dometic heaters. Electric mode fails from no 120 V, bypass position, a tripped ECO, or a failed element.
ElectricLochinvar Electric Water Heater Troubleshooting
A Lochinvar electric tank not heating usually has a tripped breaker, a popped ECO, a failed element, or a thermostat fault. How to narrow it.
TroubleshootingLow Pressure After a New Water Heater
Low pressure after a new heater is closed valves, debris, or skinny flex — not a booster. Run the cold-vs-hot test.
TanklessMarey Tankless Water Heater Not Igniting
A Marey gas tankless that won't ignite usually has dead batteries, too little water flow, an LP supply problem, or an E1 ignition lockout.
TanklessNavien Condensate Drain Leaking
A wet Navien condensate fitting is a trap, slope, freeze, or loose union — not always a dead exchanger. Fix the drain path first.
TanklessNavien Constantly Running: Recirc or Leak
A Navien that never seems to stop is usually the recirculation pump. If the burner itself keeps firing, suspect a stuck flow sensor or a leak.
TanklessNavien Dead After a Power Outage
A Navien that won't heat after a power outage may have a tripped GFCI, a display set to Off, a lockout code, or freeze damage. What to check.
TanklessNavien DHW Wait: Why Hot Water Is Late
A long wait for Navien hot water is usually pipe length, recirculation turned off, or a combi unit prioritizing heat. How to time and diagnose it.
TanklessNavien E003: Ignition Failure Lockout
Navien E003 means ignition failure: the unit tried to light and never proved flame. Common causes, a safe reset, and when to call a pro.
TanklessNavien Error 598-00: RTC / Display Fault
Navien error 598-00 is a real-time clock fault on the front display board, not a heating failure. What to try and when the display needs replacing.
GasNavien Exhaust Smells Like Gas? Leave
Gas odor at a Navien termination is an emergency. Leave and call the gas utility from outside; do not restart the unit.
TanklessNavien Goes Cold After a Few Minutes
A Navien that goes cold after a few minutes usually has low flow, a recirculation cold slug, flame loss (E012), or scale overheating (E016).
TanklessNavien Knocking Noise: What It Means
Distinguish when a Navien knocks: during ignition, water flow, or heating. Record the pattern and recognize when the unit needs service.
TanklessNavien Leaking From the Bottom
Bottom drip on a Navien is condensate, a fitting, the PRV, or a heat exchanger. Identify the fluid, then shut it down.
TanklessNavien Low Pressure? Find the Restriction
Navien low hot-water flow is a clogged inlet filter, scale, valves, or undersize — not a booster setting. Diagnose it.
TanklessNavien Tankless Vibration Under Fire
A Navien that vibrates while firing is usually the recirculation pump, combustion fan, scale, or loose mounting. How to identify the source.
TanklessNavien Tankless Water Heater Exhaust Blockage
A blocked Navien exhaust can cause a lockout, gas odor, or no heat. Check the termination from outside.
TanklessNavien Tankless With No Water Flow
No water through a Navien usually means closed isolation valves, a clogged inlet filter, scale, a failed mixing valve, or frozen pipes.
TanklessNavien Water Heater Error 773-00
Navien 773-00 points to a model-specific control or communication fault. Photograph the display, power-cycle once.
TanklessNavien Water Heater Not Getting Hot
A Navien that never reaches its set temperature may be undersized, scaled, limited by a mixing valve, crossed over, or short on gas supply.
TanklessNavien Water Heater Not Turning On
A Navien that won't turn on usually has no 120 V, a display set to Off, no flow signal, or a lockout. Safe checks before calling a technician.
ElectricNew AO Smith Electric Not Heating
A new AO Smith electric that is ice-cold is fill, 240 V, ECO, or an install miss. Do not dry-fire it.
ElectricNew Element, Still No Hot Water
Replaced an element and still no hot water? The other element, the thermostat or ECO, a breaker, the wiring, or a dry fire may be to blame.
TroubleshootingNew T&P Valve Still Leaking? Why
A new T&P that weeps is debris on the seat, still-high pressure, or no expansion tank. Do not cap it.
TroubleshootingNew Water Heater Has Water in the Pan
Water in the pan under a new heater is often condensation, T&P discharge, a loose fitting, or a drain valve, not a failed tank. How to tell.
ElectricNew Water Heater Keeps Tripping the Breaker
A new electric water heater that trips its breaker may have a dry-fired element, a wiring fault, or an undersized breaker. Why it must stay off.
TroubleshootingNew Water Heater T&P Keeps Opening
A new heater's T&P valve opening repeatedly usually points to thermal expansion or high house pressure, not a bad heater. Causes and next steps.
TroubleshootingNo Hot Water After Flushing the Tank
Cold showers after a flush are a dry-fire, tripped ECO, out pilot, or a breaker. Do not reset empty.
TanklessNoritz Code 11: Ignition Failure
Noritz code 11 means ignition failure: the unit tried to light but never proved flame. Common causes, a safe reset, and when to call a pro.
TanklessNoritz Code 12: Flame Failure
Noritz code 12 means flame failure: the burner lit, then lost flame. Common causes like gas supply and venting, and when repeats need a pro.
TanklessNoritz Code 29: Neutralizer Lockout
Noritz code 29 means the condensate neutralizer cartridge needs service. What it means, how it's cleared, and when a repeat code needs a pro.
TanklessNoritz Leaking From the Bottom
Water under a Noritz can be condensate, a relief valve discharge, a filter or drain plug gasket, or the heat exchanger. How to identify it.
TanklessNoritz Tankless Not Hot Enough
A Noritz running lukewarm may be undersized, scaled, limited by a mixing valve, crossed over, short on gas, or simply set too low.
TanklessNoritz Tankless Water Heater Not Working
A Noritz tankless that won't heat usually has a power, flow, lockout, freeze, or gas problem. Read the code first, then follow the checks.
TanklessNoritz Tankless With No Hot Water
A Noritz with no hot water usually has no 120 V, no flow signal, a lockout code, or a gas or ignition fault. Read the display first.
TanklessNoritz Tankless With No Water Flow
No water through a Noritz usually means closed isolation valves, a clogged inlet screen, scale, a failed mixing valve, or frozen pipes.
RVOasis Heater Dead? Name the Module First
On motorhomes, Oasis usually means an ITR diesel hydronic system. Cold showers trace to coolant, flame-out, 12 V, the pump, or a mixing valve.
TroubleshootingPhase 3 Water Heater Troubleshooting
Identify a Triangle Tube Phase III water heater before troubleshooting. Separate indirect-tank and gas-fired models and find the appropriate manual.
GasPilot Dies When You Turn the Temp Dial
If the pilot goes out when you turn up the temperature dial, suspect millivolt sag, a weak valve magnet, or the main burner lifting the flame.
GasPilot Light Goes Out in Cold Weather
A pilot that goes out in cold weather is often caused by drafts, LP that won't vaporize, a sealed closet, or a clogged FVIR screen.
GasPilot Lit but Main Burner Never Opens
Pilot lit but the main burner won't come on? Check the knob and temperature setting, then suspect a weak thermopile, an ECO, or the gas control.
GasPilot Still Dies After New Thermocouple
Pilot still goes out after a new thermocouple? The part may be wrong or out of the flame, or the gas valve magnet may have failed.
TroubleshootingPolaris Water Heater Problems: Real Fixes
Polaris condensing water heater lockouts usually involve blocked condensate, hot-surface ignition, the blower, or scale. Safe checks first.
GasPower-Vent Water Heater Blower Not Working
A power-vent blower that won't run keeps the gas valve closed for good reason. What to check, and why the burner must never fire without it.
TanklessQuietSide Tankless Water Heater Problems
QuietSide tankless and combi units fail on ignition, fan or pressure switch, low loop water, or a stuck 3-way valve. What the codes mean.
TroubleshootingReliance 6-06: No Heat, Light, or a Leak
The Reliance 6-06 is an A. O. Smith-built gas or electric tank. Diagnose no heat, the status light, or a leak by fuel type.
TroubleshootingReliance Status Light Not Blinking
A dark Reliance status light can mean the pilot is out, a dead thermopile, the control is off or failed, or no power on electric models.
TroubleshootingReliance Water Heater Leaking: Find the Source
A Reliance leak can come from the drain valve, T&P, a fitting, an element gasket, or the tank itself. How to find the wet part and what it means.
GasReliance Water Heater Won't Light
A Reliance gas water heater that won't light usually has a closed gas cock, empty LP, a lockout, a failed igniter, or an FVIR trip.
GasReplace a Gas Water Heater Burner Assembly?
A rusty burner can signal a leaking tank rather than a bad burner. When a gas burner assembly is worth replacing, and when the tank is done.
RVReplacing an Atwood Water Heater Element
Atwood/Dometic RV elements are 120 V, around 1400 W. How to test one with power off, what else stops electric heat, and when to stop.
GasReset a Locked-Out Honeywell Water Heater
Resetting a Honeywell/Resideo water heater means turning the control to OFF, waiting, and restarting, not pressing a button. When to stop.
ElectricRheem A108 Error: Condensate Blocked
Rheem hybrid A108 means the condensate sensor is wet or the drain is blocked. How to clear the drain safely and when a repeat code needs a pro.
GasRheem Blue Light Flashing 7 Times
Seven flashes on a Rheem, Ruud, or Richmond gas control indicates a lockout, often FVIR related. What it means and why it must not be bypassed.
TanklessRheem Code 11: Ignition Failure
Code 11 on a Rheem tankless means ignition failure: the unit never proved flame. Common causes, one safe reset, and when to call a technician.
GasRheem Failed Ignition Lockout
A Rheem failed-ignition lockout means spark or glow didn't produce proven flame. How to read the LED or code and when a reset is appropriate.
GasRheem Gas Control or Valve Failure
Rheem gas control faults usually come from a weak thermocouple or thermopile, an LED lockout, a clogged flame arrestor, or a failed valve.
ElectricRheem Heat Pump Water Heater Problems
A Rheem hybrid not heating may have a dirty filter, vacation mode, an EcoNet code, a tripped ECO, a failed element, or a compressor lockout.
GasRheem Pilot Light Will Not Stay Lit
A Rheem pilot that dies is a thermocouple, FVIR screen, or gas valve — not a ritual relight. If you smell gas, leave and call a pro.
TroubleshootingRheem Plastic Drain Valve Leaking
Locate a possible Rheem drain-valve leak without forcing the valve. Distinguish tracked water, a leaking outlet, and a tank problem.
GasRheem Pressure Switch Failed Open
Pressure switch failed open on a Rheem power-vent means draft was never proven: a blocked vent, condensate, a cracked hose, or a failed blower.
GasRheem Red Light Flashing 9 Times
Nine red flashes on a Rheem, Ruud, or Richmond gas control is a lockout, usually the chamber temperature sensor. What it means and next steps.
TanklessRheem Tankless Error Code 12: Flame Loss
Rheem tankless code 12 means the burner lit and then lost flame. Common causes like gas supply and venting, a safe reset, and when to stop.
TanklessRheem Tankless Leaking Inside the Cabinet
Water inside a Rheem tankless cabinet can be condensate, relief valve discharge, an O-ring, or the heat exchanger. How to identify the source.
GasRheem Tankless Smells Like Gas? Leave
A gas smell at a Rheem tankless should be treated as a leak until a professional says otherwise. What to do, and which odors aren't gas.
TanklessRheem Tankless Water Heater Flashing 11
Rheem tankless code 11 means ignition failure: no flame was proven. Common causes like a closed gas cock or dirty flame rod, and one safe reset.
TanklessRheem Tankless Water Heater Troubleshooting
A Rheem tankless that won't heat usually has a power, flow, lockout, freeze, or gas problem. What codes 11, 12, and 14 mean.
GasRheem Thermopile Voltage Low
Low thermopile voltage on a Rheem millivolt gas valve can shut off the burner or darken the LED. Causes, what to check, and when to call a pro.
TroubleshootingRheem Water Heater Keeps Turning Off
A Rheem that heats and then shuts off has tripped a safety: an ECO, FVIR, thermopile, pressure switch, or tankless lockout. How to find which.
TroubleshootingRheem Water Heater No Status Light
A dark Rheem status light can mean no 240 V, a failed thermostat or ECO on electric models, or a pilot, thermopile, or control fault on gas.
TroubleshootingRheem Water Heater Not Heating
A Rheem not heating needs different checks for gas and electric: breaker, ECO, elements, and thermostat, or pilot, FVIR, and gas control.
GasRheem Water Heater Smells Like Gas? Leave
A gas smell at a Rheem, Ruud, or Richmond water heater should be treated as a leak. What to do right away, and which smells are not fuel.
GasRheem Water Heater Won't Light
A Rheem gas water heater that won't light usually has a closed gas cock, empty LP, a lockout, a failed igniter, or no gas supply.
GasRichmond Water Heater Gas Valve Problems
Richmond gas-valve faults are a weak thermopile, FVIR lockout, or a failed control. Do not purge fittings.
TroubleshootingRichmond Water Heater Has No Hot Water
A Richmond with no hot water needs a different check for gas and electric: breaker, ECO, element, or thermostat versus pilot, FVIR, or control.
TroubleshootingRichmond Water Heater Leaking: Find the Source
A Richmond leak can come from the drain valve, T&P, a fitting, an element gasket, or the tank itself. How to find the wet part and what it means.
TroubleshootingRichmond Water Heater Troubleshooting
Richmond water heaters use Rheem hardware. Diagnose a cold, flashing, or leaking unit by fuel type: element, ECO, gas lockout, or leak.
TanklessRinnai Beeping With Code 17
Rinnai code 17 on SENSEI units means a venturi blockage in the air/gas mixer. What to check first and why the gas valve should stay closed up.
TanklessRinnai Code 14: Thermal Fuse Lockout
Rinnai code 14 means the thermal fuse or overheat circuit is open. Why it happens, why it must not be bypassed, and when a repeat needs a pro.
TanklessRinnai Constantly Running: Recirc or Leak
A Rinnai that seems to run nonstop is usually recirculation or freeze protection. If the burner keeps firing, suspect a flow sensor or a leak.
TanklessRinnai Control Panel Not Working
A blank or frozen Rinnai controller usually means no 120 V, a panel set to Off, a damaged cable, or a board fault, not a failed heater.
TanklessRinnai Dead After a Power Outage
A Rinnai that won't heat after a power outage may have a tripped GFCI, a controller set to Off, a lockout code, or freeze damage.
TanklessRinnai Error Code 12: Flame Failure
Rinnai code 12 means the burner lit and then lost flame. Common causes like gas supply, venting, or a dirty flame rod, and when to stop resetting.
TanklessRinnai Goes Cold After a Few Minutes
A Rinnai that goes cold after a few minutes usually has flow dropping below minimum, flame loss (code 12), or scale overheating (code 16).
TanklessRinnai Hot Water Heater Code 10
Rinnai code 10 means blocked air supply or exhaust. Common causes like snow, nests, or a crushed vent, and why the unit shouldn't keep firing.
TanklessRinnai Humming Noise: What It Means
A Rinnai hum may involve normal operation, a fan, or a circulation pump. Note when the sound changes and when professional diagnosis is needed.
TanklessRinnai In Use Light Not On
A dark In Use light means no flow, no power, or a dead remote — the burner never started. Diagnose it.
TanklessRinnai Leaking by Exhaust When Turned Off
Water at a Rinnai flue after shutdown is condensate, rain, or a cracked exchanger. Do not silicone the vent.
TanklessRinnai Leaking From the Bottom
Water under a Rinnai can be condensate, relief valve discharge, or a heat exchanger or internal fitting leak. How to tell which you have.
TanklessRinnai Low Pressure? Find the Real Cause
Low pressure at a Rinnai is usually the inlet screen, scale, isolation valves, or a fixture crossover — not a dying pump. Diagnose it.
TanklessRinnai Not Getting Hot Enough
Lukewarm Rinnai water is undersize, scale, a mixing valve, or gas — not a hidden turbo. Measure inlet temp and GPM.
TanklessRinnai R53 Problems: Real Field Fixes
Common Rinnai R53 problems: vent or air faults (10), ignition or flame loss (11/12), and overheating from scale or low flow (16).
TanklessRinnai Takes Too Long for Hot Water
A slow Rinnai is usually pipe lag, no recirc, scale, or a unit undersized for the shower. Fix the real delay.
TanklessRinnai Tankless Water Heater Frozen
A frozen Rinnai needs power, freeze protection, and a leak check before restart. Do not fire a split unit;
TanklessRinnai Tankless With No Hot Water
A Rinnai with no hot water usually has no 120 V, no flow signal, a lockout code, or a gas or ignition fault. Read the display first.
TanklessRinnai Tankless With No Water Flow
No water through a Rinnai usually means closed isolation valves, a clogged inlet screen, a seized flow sensor, or a scaled heat exchanger.
TanklessRinnai TPR Valve Leaking? Stop It Safely
A dripping Rinnai T&P valve means excess pressure or heat. Find the real cause, stop the leak path,.
TanklessRinnai Water Heater Code 25
Rinnai code 25 is a condensate problem: a full trap, a kinked or frozen hose, or a failed condensate pump. What to check and when to call a pro.
TroubleshootingRuud Hot Water Heater Troubleshooting
Ruud is Rheem's wholesale brand. Diagnose a cold, flashing, or leaking Ruud by fuel type: element, ECO, gas lockout, or a leak.
RVRV Water Heater Fault Light On
The red light on an RV water heater switch usually means a DSI ignition lockout. What it means, one safe reset, and when to stop.
RVRV Water Heater Fires Up Then Goes Out
An RV water heater that lights and then goes out is losing flame: low LP, a dirty sense electrode, an ECO or thermal fuse, or a regulator issue.
RVRV Water Heater Leaking From the Bottom
Water at the bottom of an RV water heater can come from the drain plug, P&T valve, anode, bypass fitting, or the tank. How to find the source.
RVRV Water Heater Leaking Outside
Water under an RV water heater door can come from the drain plug, T&P, anode, element gasket, or the tank. How to find the wet part.
RVRV Water Heater Not Getting Hot Enough
Lukewarm RV hot water is usually a half-open bypass valve, one heat source not working, or a mixing valve. How to find the cause.
RVRV Water Heater Pressure Relief Dripping
An RV water heater relief valve that drips usually reacts to high city-water pressure, heating without an air pocket, or a dirty seat.
RVRV Water Heater Smells Like Rotten Eggs
Rotten-egg smell only in RV hot water usually comes from the anode or stagnant water. The same smell in the air may be propane. How to tell.
ElectricSeisco Tankless Water Heater Troubleshooting
A Seisco tankless not heating usually has a missing 240 V leg, air in the chamber, a high-limit trip (122), or a leak detect code (126).
TroubleshootingSharkBite Water Heater Connector Leaks
A leaking SharkBite water-heater connection needs its source and installation checked. Learn what to observe and when to arrange a repair.
ElectricSioGreen Tankless Water Heater Problems
Identify the SioGreen model, distinguish power and flow symptoms, and check heating demand without opening the cabinet or guessing error codes.
GasSmell Gas After Lighting the Water Heater?
A gas smell after lighting a water heater may be unburned fuel or a leak at the control. Why you should leave, not relight, and who to call.
GasSmell Gas When the Water Heater Turns On?
A gas smell only when the burner fires can mean a leak or delayed ignition. Why you should leave and call for help rather than keep cycling it.
TroubleshootingSolar Water Heater No Hot Water in the Morning
A solar water heater cold in the morning may have a freeze dump, a pump running overnight, a stuck mixing valve, or a failed backup heater.
ElectricState Hybrid Water Heater ECC Code
ECC on a State hybrid water heater means the heat pump compressor isn't working. Backup elements may still heat. What to check and when to call.
GasState Select Gas Water Heater Troubleshooting
A State Select gas water heater that won't heat usually has a pilot, thermocouple, FVIR, or control LED fault. How to read it safely.
GasState Select Igniter Not Working
A State Select that won't light usually has a hot-surface igniter that never glows, a control lockout, or no 120 V at the valve.
GasState Select Pilot Light Won't Stay Lit
A State Select pilot that goes out when you release the knob usually has a thermocouple not proving flame, or a clogged FVIR arrestor.
TroubleshootingState Select Water Heater No Hot Water
A State Select with no hot water needs different checks for electric and gas: breaker, ECO, and element versus igniter, FVIR, and gas control.
ElectricState Select Water Heater Reset Button
The State Select reset is an electric high-limit (ECO) on the upper thermostat. How to press it safely, and what a repeat trip means.
ElectricStiebel Eltron Water Heater Not Turning On
A Stiebel Eltron that stays off needs power, flow, filter, or control checks. Leave repeat trips off.
RVSuburban Igniter Clicking With No Spark
Suburban DSI click with no flame is a cracked electrode, melted wire, or lockout. Test spark with LP off.
RVSuburban RV Heater Not Working on Gas
If a Suburban RV heater works on electric but not propane, record the model and ignition sequence. Leave spark and fuel-system tests to a technician.
RVSuburban RV Water Heater Leaking
A leaking Suburban RV heater may be a plug, relief valve, fitting, or split tank. Shut it down safely.
RVSuburban SW10DE Troubleshooting Guide
Suburban SW10DE not heating on gas or electric? Check the ECO, bypass valves, shore power, DSI board, and igniter, starting with a full tank.
RVSuburban SW6DE Troubleshooting Guide
Suburban SW6DE not heating on gas, electric, or both? Check the ECO, bypass valves, shore power, and DSI ignition, and never heat an empty tank.
RVSuburban Tankless Troubleshooting
A Suburban Nautilus tankless not heating usually has an E1/E2 ignition lockout, low flow, low 12 V, an overheat code, or freeze damage.
RVSuburban Water Heater Not Working on Electric
Suburban works on gas but not electric? Suspect no 120 V, bypass valves, a tripped ECO, or a failed element. How to check safely.
TroubleshootingSuperStor Indirect Heater Problems Fix
SuperStor no-heat, leaks, and popping have a short list: aquastat, boiler priority, coil air, or a dead tank. Know when to stop DIY.
TroubleshootingT&P Leaking After You Tested It
You lifted the test lever and the T&P will not reseat — mineral on the seat, not a new tank. Do not cap it.
TroubleshootingT&P Leaking on a New Water Heater
A T&P valve weeping on a new heater usually means thermal expansion, high house pressure, or debris on the seat. Why it must never be capped.
TroubleshootingT&P Overflow Discharging? Do Not Cap It
A T&P overflow that keeps dumping is expansion, high psi, overheat, or a failed valve. Do not cap it.
TroubleshootingT&P Valve Stuck Open? Isolate, Don't Cap
A T&P valve streaming water may be stuck open or reacting to real overpressure. How to isolate the heater safely, and why it must never be capped.
TanklessTakagi Code 111: Ignition Failure
Takagi code 111 means ignition failure after three tries. Common causes like a closed gas cock or dirty flame rod, a safe reset, and next steps.
TanklessTakagi Tankless Leaking: Find the Source
Water under a Takagi can be condensate, relief valve discharge, an O-ring at the filter or water valve, or the heat exchanger. How to tell.
TanklessTakagi Tankless Problems: Codes & Fixes
Takagi tankless not heating? Most lockouts are air or exhaust faults (10), ignition or flame loss (11/12), or overheating from scale (14/16).
TanklessTakagi Tankless Vibration Under Fire
A Takagi that rattles while firing is usually scale in the heat exchanger, the combustion fan, a recirculation pump, or rigid mounting.
TanklessTakagi Tankless Water Heater Not Heating
A Takagi tankless that will not heat needs flow, power, gas, ignition, or scale checks. Photograph the code.
TroubleshootingTankless Coil Heater Problems: Real Fixes
Lukewarm or rusty water from a boiler's tankless coil usually means scale in the coil, a failed mixing valve, or domestic hot water priority issues.
TanklessTankless Dead After Rain? Diagnose It Fast
A tankless that dies after rain is usually a wet vent, soaked PCB, or tripped GFCI. Safe checks first, then a licensed tech if it stays dark.
TanklessTankless Draining Excessively? Find the Source
A tankless that dumps water is condensate, T&P, freeze drain, or an exchanger. Identify the fluid first.
GasTankless Exhaust Smells Like Gas? Leave
A gas smell at a tankless exhaust can mean unburned fuel or a leak. What to do right away, and which harmless smells are sometimes mistaken for gas.
TanklessTankless Goes From Hot to Cold Mid-Shower
A tankless that swings from hot to cold mid-shower is usually low flow, a cold-water sandwich, scale, or a plumbing crossover. How to tell which.
ElectricTankless Keeps Tripping the Breaker
An electric tankless that trips 240V is a grounded chamber, miswire, or undersized breaker. Lock it off.
TanklessTankless Leaking After a Freeze
A tankless leaking after a freeze is a split exchanger or fitting, not a drip to ignore. Shut water and power.
TanklessTankless Pressure Drop: Diagnose It Right
A tankless pressure drop is a clogged screen, scale, valves, or undersize — not a magic setting. Run the cold-vs-hot test, then call a pro.
TanklessTankless Takes Too Long? Time the Delay
A slow tankless is pipe lag, no recirc, or scale — not a hidden turbo button. Time the nearest vs farthest faucet, then hire a pro.
TanklessTankless Water Heater Banging? Shut It Down
A banging tankless can mean delayed ignition, scale boiling in the heat exchanger, or water hammer. How to tell which, and when to shut it down.
TanklessTankless Water Heater Clicking Noise
A clicking tankless is usually ignition spark, a gas valve solenoid, a relay, or a check valve. When clicking with no flame means stop.
TanklessTankless Water Heater Groaning Noise
A groaning tankless is usually scale in the heat exchanger, a dry condensate trap, or a failing fan bearing. How to identify the sound.
TanklessTankless Water Heater Smells Like Sulfur
Sulfur smell only in tankless hot water usually comes from well water or bacteria. A sulfur smell in the air may be a gas leak. How to tell.
TanklessTankless: No Hot Water at the Kitchen Sink
Kitchen cold while the shower is hot is an aerator, crossover, or min-flow — not a new unit. Diagnose it.
RVThor Water Heater Dead? Read the Door Badge
Thor coaches use Suburban, Atwood/Dometic, Truma, or other tankless heaters. Identify the unit behind the exterior door before troubleshooting.
TroubleshootingTriangle Tube Problems: No Heat to Leak
Triangle Tube units are indirects, combi boilers, or coils. Cold showers usually trace to a sensor, pump, 3-way valve, priority, or a lockout.
RVTruma AquaGo Problems: Field Fixes
AquaGo no-heat is 12V, LP, the water filter, freeze lock, or ignition — not a generic RV tank. Decode it.
RVTruma Water Heater Flashing Light Codes
A flashing Truma AquaGo or Combi light signals a lockout or warning. How to read the blink pattern or code, and when one reset is reasonable.
TroubleshootingTurn Off the Heater If the Water Is Off
Yes: if the water supply is off, turn off the water heater's power or gas before the tank can empty. Why it matters and how to do it safely.
TroubleshootingTurned On a Water Heater Without Water?
Dry-fire kills electric elements in seconds and can warp a gas tank. Lock the breaker. Do not reset the ECO and walk away.
GasUnitrol Water Heater Gas Valve Problems
Robertshaw Unitrol standing-pilot problems usually come from the thermocouple, ECO, a weak magnet, or gas supply. Why the valve stays pro-only.
TroubleshootingUS Craftmaster: No Heat, Flashes, or a Leak
U.S. Craftmaster tanks share A. O. Smith/State hardware. Diagnose a cold, blinking, or leaking unit by counting the LED and finding the wet part.
TroubleshootingVaughn Hydrastone Water Heater Problems
Vaughn no-heat is the coil, sensor, or zone — not a pilot. A wet O-ring flange is a repair; a wet shell is not.
TroubleshootingWater Coming From the Top of the Heater
Water at the top of a tank heater is usually the T&P, anode, a nipple, heat trap, connector, or element gasket, not the tank. How to find it.
TroubleshootingWater Dripping From Water Heater Exhaust
Water dripping from a water heater exhaust can be normal condensate, rain, a blocked condensate drain, or a cracked heat exchanger.
TroubleshootingWater Dripping Inside the Water Heater
Water inside a water heater jacket may come from a nipple, element gasket, condensate, T&P, or the tank. How to find the source safely.
GasWater Dripping on a Gas Water Heater Burner
Water near a gas burner may be condensation, tracked water, or a tank leak. Keep wet equipment off and have the source and combustion safety assessed.
GasWater Dripping on the Water Heater Pilot
A wet pilot is T&P tracking, draft-hood drip, or a tank leak at the door. Rust at the chamber means shut gas.
TroubleshootingWater Heater Alarm Going Off? Find the Beep
A beeping water heater is usually a tankless lockout, hybrid alarm, power-vent board, or leak sensor, or a nearby smoke or CO alarm.
TroubleshootingWater Heater and Furnace Both Dead at Once
Both dead at once is a shared vent, gas meter, or circuit - not two random failures. Leave if you smell gas.
TroubleshootingWater Heater Beeping After a Power Outage
A water heater beeping after an outage usually has a tankless or hybrid lockout, a dry-fire alarm, a power-vent fault, or a leak sensor alert.
TroubleshootingWater Heater Beeping and No Hot Water
Beeping with no hot water usually means a tankless or hybrid lockout, a dry-fire alarm, a power-vent fault, or a leak sensor that cut the heat.
GasWater Heater Blinking Blue Light
A blinking blue light is usually the status LED on a Rheem, Ruud, or Richmond gas control. How to count the flashes and what the codes mean.
TroubleshootingWater Heater Blinking Red Light
A blinking red water heater light is usually a fault, not normal operation. How to count the flashes and read them for gas, electric, and tankless.
ElectricWater Heater Breaker Buzzing? Leave It Off
A buzzing water heater breaker can mean a loose connection, a failing breaker, or overload. Why it should stay off until an electrician checks it.
ElectricWater Heater Breaker Getting Hot
A hot water heater breaker usually points to a loose connection or failing contact. Why it should stay off until an electrician inspects it.
ElectricWater Heater Breaker Tripped and Won't Reset
Leave a water-heater breaker off if it will not reset. Distinguish the symptoms and prepare for professional electrical diagnosis.
TroubleshootingWater Heater Burning Smell: Shut It Down
A burning smell from a water heater can mean scorched wiring, an overheated thermostat, hot insulation, or delayed ignition. When to shut it down.
TroubleshootingWater Heater Buzzing Noise: What It Means
A buzzing water heater may be a transformer, element, gas valve solenoid, blower, or the breaker. How to identify the source and what it means.
GasWater Heater Chamber Sensor Failure
A water heater chamber sensor failure is a flammable-vapor or combustion-chamber safety lockout. What it means and why it must not be bypassed.
TroubleshootingWater Heater Check Valve Leaking
A leak near a water heater check valve may be the valve body, a heat-trap nipple, or a recirculation check. How to isolate and identify it.
GasWater Heater Closet Smells Like Gas? Leave
Gas odor in a heater closet is an emergency. Leave, call the utility from outside. Do not soap fittings.
TroubleshootingWater Heater Clunking Sound: What It Means
A clunking water heater is often a check valve, recirculation pump, broken dip tube, or tankless diverter. How to tell it from other noises.
TroubleshootingWater Heater Dip Tube Failure Symptoms
A failed dip tube gives a short burst of hot water followed by lukewarm water. Symptoms, how to confirm it, and when to call a plumber.
ElectricWater Heater Element Keeps Burning Out
A water heater element that keeps failing usually points to sediment, dry firing, a grounded element, or the wrong wattage. How to find the cause.
ElectricWater Heater Element Not Working
An electric water heater element can fail open or grounded, or the real fault may be the ECO or breaker. How to test safely with power off.
ElectricWater Heater Element Troubleshooting
Learn what element faults can look like, what symptoms cannot prove, and which information helps a qualified technician diagnose an electric heater.
GasWater Heater Exhaust Blower Noise
A squeal or grind from a power-vent blower usually means a failing bearing or condensate in the housing. When to stop running the heater.
TroubleshootingWater Heater Fan Keeps Running
Record whether a water-heater fan runs during demand, cooldown, or continuously. Burning odor and abnormal operation need prompt assessment.
GasWater Heater Flame Too High? Shut Gas Off
A lifting or sooting flame is overfire, wrong orifice, or high manifold pressure. Shut the gas cock.
ElectricWater Heater Fuse Keeps Blowing
A water heater fuse that keeps blowing points to a short, wet control, failed element, or overloaded circuit. Leave it off and hire a pro.
TroubleshootingWater Heater Gasket Leak? Name the Seal
A gasket leak is an element, cleanout, or flue seal — not always a dead tank. Paper-towel the source.
TroubleshootingWater Heater Hissing After a Shower?
Hiss after a shower is sediment on the element or burner, a simmering T&P, or steam from a dry-fire. Not normal.
TroubleshootingWater Heater Leaking After a Power Outage
A water heater leak after a power outage is often T&P discharge, a failed condensate pump, or freeze damage. How to find the source.
TroubleshootingWater Heater Leaking From an Outside Pipe
A wet pipe outside the tank is a nipple, T&P, drain, or outdoor union — not always a dead shell. Name it.
TroubleshootingWater Heater Leaking From the Top Plastic Plug
A leak at a plastic plug on top of a water heater is usually the anode, heat trap, or a capped port, not the tank. How to identify it.
GasWater Heater Leaking From the Vent Collar
Water at a water heater vent collar can be condensate, rain, a fitting above, or a tank leak at the flue. When it becomes a CO concern.
TroubleshootingWater Heater Leaks When the Washing Machine Runs
A leak that appears only when the washer runs is often T&P discharge from a pressure spike, a connector, or the washer's own hoses.
GasWater Heater Made a Loud Bang? Stop
A loud bang from a gas water heater usually means delayed ignition. Why it should be shut down, and how to tell it from sediment or pipe noise.
TroubleshootingWater Heater Making a Gurgling Noise?
A gurgling water heater usually means air, condensate in a trap or vent, a lifting T&P valve, or sediment. How to identify the sound.
TroubleshootingWater Heater Making a Hissing Noise?
A hissing water heater can mean sediment, a simmering T&P, steam from a leak, or a gas leak. How to tell which, and when to shut it down.
GasWater Heater Not Getting Any Gas
No gas at the heater is a closed cock, empty LP, locked meter, or a dead valve. Do not crack fittings.
GasWater Heater Piezo Igniter Won't Spark
A piezo igniter with no click or no spark may be a dead igniter, a wet electrode, a broken wire, or a wide gap. How to test it safely.
GasWater Heater Pilot Assembly Replacement
Pilot assembly replacement applies only to standing-pilot heaters. How to identify the actual failure first, and why gas fittings need a pro.
TroubleshootingWater Heater Pressure Relief Valve Not Working
A T&P valve that will not open, reseat, or discharge safely is an emergency. Never cap it; shut energy down.
TroubleshootingWater Heater Problems in a Crawl Space
Leaks, no heat, or venting problems with a crawl-space water heater. What to do first, and when access issues mean calling a licensed plumber.
TroubleshootingWater Heater PVC Pipe Leaking? Name It
A PVC pipe leaking at a water heater may be a condensate drain, a vent joint, or a T&P discharge line. How to tell which pipe and why it matters.
TroubleshootingWater Heater Shuts Off After 5 Minutes
A 5-minute shutdown is flame rollout, ECO, tankless min-flow, or overheat — not a generic lockout. Stop resetting it.
TroubleshootingWater Heater Smells Like a Dead Animal?
Rotten-egg HOT water is the anode. Mercaptan in AIR is a gas leak — leave. A rodent in the FVIR is different.
TroubleshootingWater Heater Sounds Like Rocks Inside
Rocks or popcorn sounds in a tank heater are usually sediment on the tank bottom. When noise is harmless and when it signals a failing tank.
TroubleshootingWater Heater Sounds Like Running Water
A water heater that sounds like running water with taps closed may be discharging its T&P, running recirculation, or leaking. How to find it.
TroubleshootingWater Heater Status Light Blinking 3 Times
Three flashes on a water heater status light means different faults by brand: an ECO trip, a thermistor, or a pressure switch that won't close.
TroubleshootingWater Heater Status Light Blinking 6 Times
Six flashes on a water heater status light can mean a thermostat or thermistor fault on electric models, or an FVIR or valve fault on gas.
TroubleshootingWater Heater Suddenly Too Hot
Suddenly scalding water means a thermostat, gas control, sensor, or mixing valve fault. Shut the heater down.
TroubleshootingWater Heater Switch Not Working
A water heater switch that does nothing may be a tripped disconnect, a blown fused pullout, an RV rocker switch, or a tripped breaker.
TroubleshootingWater Heater Temperature Control Dead
A water heater temperature control that does nothing may be an ECO lockout, a failed thermostat, a gas valve fault, or a mixing valve.
TroubleshootingWater Heater Thermal Fuse Open
A water heater thermal fuse means different parts on tankless, RV, gas, and electric units. What an open fuse means and why it's never bypassed.
GasWater Heater Thermocouple Problems
A thermocouple that won't hold the pilot may be out of the flame, loose, or dead, or the gas valve magnet may have failed. Readings and next steps.
TroubleshootingWater Heater Ticking Like a Clock?
A clock-tick is pipe expansion, a recirc check valve, or tankless post-purge — not harmless. Name the tick.
GasWater Heater Vent Pipe Leaking? CO Risk
Water on a water heater vent pipe can be condensate, rain, or a failed joint. Why a leaking vent can be a carbon monoxide risk.
TroubleshootingWater Heater Will Not Drain: Unclog Safely
A water heater that won't drain usually has a clogged plastic drain valve, a sediment plug, or no air entering the tank. How to fix it safely.
TroubleshootingWater Heater Won't Stop Draining
A water heater that won't stop draining may have a stuck T&P, an open drain valve, or a siphon through the cold inlet. How to stop it.
TroubleshootingWater Leaking From the Bottom of the Tank
A puddle beneath a water heater can come from several sources. Identify exterior clues, urgent hazards, and when repair or replacement is appropriate.
GasWater Leaking From the Gas Control Valve
Water on a gas control valve usually tracks from another fitting or a leaking tank. How to trace it, and why gas fittings should stay untouched.
ElectricWater Leaking From the Upper Thermostat
Water at the upper thermostat usually comes from an element gasket, a fitting above, or the tank itself. How to find the source with power off.
TroubleshootingWeil-McLain Indirect Water Heater Problems
A Weil-McLain AquaPlus indirect with no hot water usually has a sensor, pump, zone valve, priority, or air problem. How to narrow it down.
TroubleshootingWeil-McLain Water Heater Leaking: Find It
A Weil-McLain AquaPlus leak can come from the drywell plate, anode port, T&P, a coil union, or the vessel. How to identify the source.
GasWet Gas Water Heater Pilot Won't Light
A gas water heater that got wet may have a drowned pilot, thermocouple, or FVIR screen, or water inside the combustion chamber. What to check.
TroubleshootingWhat To Do If a Water Heater Bursts
If your water heater bursts, close the cold inlet, shut off the power or gas, and keep clear of the water. Step-by-step first actions.
GasWhirlpool Pilot Light Won't Stay Lit
A Whirlpool pilot that dies is a thermocouple, dirty orifice, or FVIR — not luck. If you smell gas, leave.
TroubleshootingWhirlpool Temperature Sensor Failure
Whirlpool temperature sensor failure means the control no longer trusts its thermistor: often 3 flashes on electric or 5 on gas models.
TroubleshootingWhirlpool Water Heater Troubleshooting
Whirlpool water heaters use A. O. Smith/American hardware. Diagnose gas and Energy Smart electric models by LED, ECO, element, or leak.
TroubleshootingWhite Smoke From a Water Heater
White vapor is often steam; combustion exhaust or electrical smoke is not. Shut it down, tell steam from fire.
TroubleshootingWhy a Water Heater Turns Off by Itself
An unexpected water-heater shutdown can involve supply, controls, or a protective device. Record the pattern instead of repeatedly resetting.
ElectricWhy Water Heater Thermostats Burn Up
Burned water-heater controls can indicate damaged connections, moisture, or an electrical fault. Keep the circuit off and arrange qualified diagnosis.
GasWhy Won't My Gas Water Heater Stay Lit?
A gas water heater that lights then dies is thermocouple, thermopile, draft, or the gas valve. If you smell gas, leave.
ElectricWhy You Keep Resetting a Water Heater
Repeated water-heater resets indicate an unresolved problem. Identify the protective device, record the symptoms, and arrange qualified service.
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Still not finding it? Try the brand and a shorter symptom or code. Model numbers appear only where a guide specifically covers them. For an urgent gas smell, flood, or electrical fault, use the safety checklist.