Gas water heater dumb question please help

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johnv713

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My gas water heater hasnt been working for a few weeks now. I followed the instruction on the side and still no flame. I saw a youtube video that suggests it could be an easy. Do gas water heater partially power by electric? Do i need to turn off the breaker in the garage. Sorry if that sounded like a dumb question. Just wanna be safe hats all. Thanks
 
Is it in fact an electronic ignition tank or is it a tankless water heater? Can you post a picture? Most residential tanked water heaters are not electronic ignition and are not plugged into an AC source unless you have a high dollar commercial one? Typically a millivolt water heater and a standing pilot.
 
Hope this pic will help. It has ignitor button on the next to the pilot/off valve

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That has no electricity to it and is a millivolt system, did you try lighting the pilot(follow the directions on the label)? There’s a small viewing window to see the pilot. If it doesn’t hold, it can be a few things. I believe that model has a black plastic plastic screen on the bottom that may need cleaning...beyond that you have a screen on the underside with thousands of holes that may be blocked with lint and dust. This is combustion air openings. If it’s caked with lint it will starve for air and not stay running. You can see it best with a small mirror and flashlight. Beyond that, you may have a bad thermocouple. Try cleaning the combustion air openings first. The thermocouple is the copper colored skinny wire on the left that goes from the control and into the burner compartment. It’s a common fail over time. If you aren’t very knowledgeable or handy, you may have to call a contractor.
 
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I followed the instruction on the label. At first both the pilot and flames ignited but only stayed on for like a Quick second. After a couple more tries none came on. My guess is the screening on the underside is plugged due to the flames instantly fizzled out. How do i remove it to clean?

Im not a handy man but not a total dud either :) i never had to replace the thermalcoupler before but i dont think changing it out beyond my capability. Thanks
 
There are rectangular openings around the perimeter at the bottom, shove a brush like these in there and brush away!! It’s about an 8” diameter metal screen with holes but some are rectangular.

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There are also models that set flat on a platform and take their combustion air from the area between the tank and the outer casing.

To access the ignitor and burner and change, or inspect the thermocouple, you'll need to turn the appliance off, disconnect the tubing and the pisiomatic ignitor from the valve. There a couple of sheetmetal screws securing the assembly to the appliance and once they are removed you can carefully remove the mechanism.

You probably find the the thermocouple is corroded and cleaning it may solve the problem, temporarily.
 
Ok i gave the screen at the bottom a thorough cleaning. Hit the ignitor button, flame came on for about 5 second then died. Which is better than before but it wont stay on. Does home depot sell thermocoupler and are they universal? Thanks
 
Ok i gave the screen at the bottom a thorough cleaning. Hit the ignitor button, flame came on for about 5 second then died. Which is better than before but it wont stay on. Does home depot sell thermocoupler and are they universal? Thanks

Some are universal and some are brand specific. What is the serial # of the appliance?
 
Yes i held it for a good min or so. The flames came on for like 5 sec then went kaput in a flash.

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I’m betting a bad thermocouple.

The pilot flame should keep burning for as long as you hold down the preheat knob even with a bad thermocouple or no thermocouple at all. All the thermocouple does is a safety feature in case the pilot blows out it wont allow the gas to come on without a source to ignite it.

That’s the way all the old ones worked anyway.

I just wanted to make sure the OP was holding down the knob in the pilot position until the thermocouple became hot enough to hold the pilot on when you turn the knob to run.


Maybe new ones work different I haven’t been around any new tanks.

The OP held it for a minute but the flame went out in 5 seconds. I didn’t understand that.
 
I just want to clarify i pushed down the knob, clicked the ignitor button, continue to hold the knob down for a minute, turn the knob to on. The flame on the burner came on for about 5 seconds then "poof" it went away. And , yes, the pilot flame stay on as long as the knob is held down.

Btw if its the screen is clog up, is the best way to clean it is to put the tank on its side? Id rather not do that since im not certain how to take it down.
 
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Thanks.

This is, "generally", what your burner assembly will appear as, after you remove it from the appliance, briefly described in post #7; https://www.supplyhouse.com/AO-Smit...rGwqPpULXXqg3sEdTvdky4F1YeUBUE8MaAh2HEALw_wcB

The thermocouple is on the end of the small copper line and it may be individually removable, and may be part of pilot shroud. You'll be able to determine that, once removed.

I was not able to find specifics about the burner assembly or thermocouple using the serial or model #, so the thermocouple may be generic.
 
I just want to clarify i pushed down the knob, clicked the ignitor button, continue to hold the knob down for a minute, turn the knob to on. The flame on the burner came on for about 5 seconds then "poof" it went away.

Working with just the pilot alone, once lit does it remain on?

If it does, this does not eliminate the thermocouple, because the thermocouple generates a voltage the the control reads and subsequently opens allowing the burner to ignite.

If the thermocouple is corroded the voltage can be to low and the burner will not operate.
 
I test thermocouples in my line of work as a service. A good thermocouple read is anything over 8 millivolt. It’s possible it could be reading 3,4 or even 5 millivolt and hold but typically isn’t enough for it to stay on very long= they get weak over time. Think of it like a car battery, it’s crucial that this be strong. No pilot, no main burner. We have testers where we can connect in series and get the read off of them. Typically the reads are 0-1 mv. Can you take a picture of the area where the burner, pilot tubes enter the compartment? If I’m not mistaken, that one has an orange boot around the main burner pipe? That particular assembly is fairly easy to swap out the thermocouple, and yes, you can use a standard 18” thermocouple, assuming that’s what’s bad. 99% of the time the thermocouple fails before the control.
 
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I just want to clarify i pushed down the knob, clicked the ignitor button, continue to hold the knob down for a minute, turn the knob to on. The flame on the burner came on for about 5 seconds then "poof" it went away. And , yes, the pilot flame stay on as long as the knob is held down.

Btw if its the screen is clog up, is the best way to clean it is to put the tank on its side? Id rather not do that since im not certain how to take it down.



NO! Don’t need to turn your tank on its side...simply swab out the underside with that brush...I thought you did that already??! Can you see with a mirror and flashlight the area I was referring to? If you swap the thermocouple, you should be able to clean it from the inside of the burner area as well? Air compressor with a nozzle would work too or spray bottle with a stream of water directed over the holes. It won’t take much. The idea is to get combustion air to those flames.
 
The pilot stay lit the whole time. I got a wire brush yesterday from Target and spent at least ten mins to clean the bottom of the heater. I might have to take out the burner assembly to clean it from the inside. If that doesnt work then i think its probably the thermal couple that needs to be replaced.
 
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