iFixit - Answers With Device "Water Heater"

Water Heater: no power in lower element?

Sat, 21 Sep 2024 10:33:43 -0700

I can't seem to get power to the lower element of my electric hot water heater the top one reads fine but the bottom one does not

⟐ Commented September 21, 2024 at 10:33 MST

Water Heater: Water heater not heating - RESOLVED

Fri, 26 Dec 2025 07:34:55 -0700

We have a GSW 3000W water heater which is not heating the water at all.

I checked some answers here and went through some checks.

We get power to both screws on both upper & lower elements.

I checked both elements for resistance and got readings of 19.6 on both.

I checked the resistance of the upper element, screws to heater body and no indication of resistance.

I have replaced the upper thermostat.

What else could be the problem?

Thank you,

Dave

⟐ Commented December 26, 2025 at 7:34 MST

Water Heater: Is the thermostat defective

Mon, 17 Feb 2014 20:36:10 -0700

My gas hot water heater is releasing water through the overflow value on a constant basis, which I think is a sign of the water is overheating. Do I need to replace the thermostat?

⟐ Answered February 17, 2014 at 20:36 MST

Water Heater: Thermostat failed, I replaced it ,its still over heating and tripping

Thu, 22 Feb 2018 09:19:26 -0700

The thermostat kept tripping so I replaced it. It fixed problem for couple months now it's tripping again. Should I replace the elements now or just one. It has upper and lower elements. It's a AO Smith that's only 4 years old is that normal.

⟐ Answered February 22, 2018 at 9:19 MST

Water Heater: The fan runs for a very short time every few minutes.

Thu, 12 Oct 2017 20:03:29 -0700

The fan on my vented water heater run for about one second every few minutes. The water heater seems to be working fine.'''

⟐ Answered October 12, 2017 at 20:03 MST

Water Heater: Richmond electric ECO water heater not heating - RESOLVED

Sun, 14 Dec 2025 10:35:46 -0700

I have a Richmond 12E50-DEC 50 gallon water heater which has digital controls in which after powering off/on with the circuit breaker can be set to heat, but oly powers the upper electric element fo around 1 minute, then the digital control disables the voltage to the heater element. Lower element never gets voltage applied.

Both elements are both 11.5 ohms and appear to be good. Am attempting to remove and measure the thermocouple but using the digital diagnostic, I observe lower on at 54 F and upper at 77F, so are somewhat reasonable values for a tank that was at room temperature and then had some water come in from the well into the lower chamber.

I understand that these controls me only turn on one heater element at a time which would explain the upper element getting voltage for 30 seconds or a minute but then unclear why the control with turn off the heat without posting any kind of error code as there are no codes in the history.

Any help would be appreciated.

Called Richmond (Rheam) customer service.The representative felt this was likely a faulty digital circuit board since no error codes were being posted in the history and due to the behavior observed where the upper element was powered for about a minute after a power cycling off/on using the circuit breaker. Service person advised me that the upper heater element would normally be powered for about 20 minutes before switching power to the lower heater element.

New circuit board being sent free of charge under the 12 year parts warranty.

⟐ Commented December 14, 2025 at 10:35 MST

Water Heater: No hot water in boiler, keeps flashing F5?

Thu, 21 Nov 2024 10:51:47 -0700

My furriol boiler keeps flashing F5, and am only getting hot water for a couple of seconds at a time, will i need to get a new boiler, or can this be fixed?

⟐ Commented November 21, 2024 at 10:51 MST

Water Heater: Ferroli DOMICompact F24B F5 error

Thu, 31 Oct 2024 09:46:29 -0700

I also have the issue of the fan not working and error code F5 as someone else posted a few years back, but in my case, the fan is ok, has continuity and resistance of 47.6 ohms and is free moving.

The issue is, the fan isn’t getting power from the PCB so is the PCB at fault or is there something else I can check? Can anyone help?

⟐ Answer accepted October 31, 2024 at 9:46 MST

Water Heater: How often does a tankless water heater need to be descaled?

Sat, 16 Dec 2023 01:01:56 -0700

I have a Rinnai RL94 Tankless hot water heater. It’s not clear to me from the owner’s manual whether the unit needs to be descaled regularly, or whether it’s all right to wait for one of the corresponding “LC” warning codes to appear. I know this depends on the hardness of my local water supply. Is this something that I would be doing pre-emptively, or is it all right to just wait for the warning?

⟐ Commented December 16, 2023 at 1:01 MST

Water Heater: Baxi Luna3 boiler runs out of hot water?

Thu, 02 Nov 2023 15:03:01 -0700

Afternoon, I have a Baxi Luna 3 Comfort Combi Unit, The boiler goes on when I open faucets or showers, But goes cold in about 5 minutes tops, Then takes forever to heat up again. Cant even take showers. The unit is 2 years old, I checked the heat exchanger and flushed it out just incase of scaling or slime. Some dirt but nothing to stop water flow. This has been a constant issue. Was a direct replacement with an old baxi unit due to hurricane sandy.

⟐ Answered November 02, 2023 at 15:03 MST

Water Heater: Worked once then quit please help me!

Wed, 15 Mar 2023 13:49:39 -0700

Purchased and installed brand new rheem 40 gallon electric water heater. It worked great when first turned it on for about a day maybe a day and a half then no more hot water. Checked all electrical connections and all is correct. Have tested everything i can think of all testing says water should be gettin hot. Does not flip breaker at all. What am i doing wrong

⟐ Answered March 15, 2023 at 13:49 MST

Water Heater: How old is my water tank 1131A016009

Sat, 04 Mar 2023 15:06:07 -0700

Model number 153.331661

⟐ Answered March 04, 2023 at 15:06 MST

Water Heater: Why won't the pilot light stay lit?

Thu, 24 Nov 2022 20:18:07 -0700

I'm trying to relight my water tank but the pilot light will not stay lit. What is the reason for this?

⟐ Answered November 24, 2022 at 20:18 MST

Water Heater: Pressure relief valve leaking

Mon, 21 Dec 2020 15:07:11 -0700

I have a leaking pressure relief valve in a electric hot water heater.it heater has been drained and off for about 6 mts, when I filled it up and it got hot it started leaking, now that it’s cooled down it’s still leaking but slower. Do I just replace the valve or is something else causing it?

⟐ Answer edited December 21, 2020 at 15:07 MST

Water Heater: How is the unit supposed to be wired to prevent overheating at connect

Thu, 19 Feb 2026 01:22:04 -0700

The Rheem Essentials on-demand electric water heater (240v, 13kW) that I have does not come with a clear diagram or instructions for wiring properly to install it correctly, not in the owners manual nor is it available online, that I can find. Using the recommended 1x6 AWG wire and 60 AMP dedicated breaker, which wires get connected to which inside the unit to power which system functions? Outside of green to green for ground, instructions say only to "connect the wires"... Where do you connect specifically the red, black, and white wires?

⟐ Commented February 19, 2026 at 1:22 MST

Water Heater: tabodd 16l gas water heater

Thu, 25 Sep 2025 23:56:37 -0700

hi .my water heater will not ignite automatically. if i turn on water and then turn on heater it ignites .but if i switch if i turn on water while its on it will not ignite. also if i leave it turned on with water off it tries to ingnite.the lcd stays on also .be great and much appreciated if anyone can help

⟐ Answer edited September 25, 2025 at 23:56 MST

Water Heater: Leaking Heat pump water heater, AO Smith HPTU-50N130

Sat, 07 Jun 2025 19:30:44 -0700

Chris Stillman

***1 minute ago

UPDATE: The leak is coming from the bottom device. I'm looking into this manual if that pulls out, etc. Any input is welcome.

***

Hello, I woke up to a nice puddle of water underneath the water heater. It is spraying water out from the inside. The water is literally spraying out from behind the section in the photo attached.

I may be in over my head on this one but figured I'd check in with you guys!

Thank you!

⟐ Commented June 07, 2025 at 19:30 MST

Water Heater: Ferroli Optimax HE 18S boiler. Error code T5.

Sat, 23 Nov 2024 09:23:58 -0700

Need help with Ferroli Optimax HE 18S boiler. Error code T5.

Have reset and got flashing P01 but nothing happens. Was working night before last. It was very cold overnight and last night wouldn't come on. Have tried to investigate this evening but all guidance says to reset and when P01 appears, system should fire up.

Nothing happening, house freezing, no other source of heating.

😢🥶

⟐ Answered November 23, 2024 at 9:23 MST

Water Heater: Mx inspiration qi Why is my water cold?

Fri, 16 Feb 2024 07:52:18 -0700

My electric shower is only running cold water. The electrics for it seem ok. But it all started after an electric trip in our house. Is there any way to resolve it?

⟐ Commented February 16, 2024 at 7:52 MST

Water Heater: A.O. Smith water heater

Mon, 09 Oct 2023 00:29:07 -0700

Water heater makes a bubbling sound when reheating water in the tank

⟐ Commented October 09, 2023 at 0:29 MST