Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Water Heater cycle

Options
hunter29
hunter29 Member Posts: 165
in Domestic Hot Water

Hi Guys, My gas water heater ( Power Vent ) is starting to malfunction. When it needs to heat it will start up , Gas will ignite then a second later it will shut down.

Then it will restart and start heating water. However it's getting worse, it will start stop a couple times now then catch and stay on.

Could this be a thermocouple going bad ?

thanks

Comments

  • Jamie Hall
    Jamie Hall Member Posts: 26,148

    It could. Or… it could be any of about half a dozen other things. Has it been serviced recently? Cleaned? Air and gas pressures checked? Combustion test done?

    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • hunter29
    hunter29 Member Posts: 165

    No, I just looked at the manual and see it can give me trouble codes.

    So I will wait for it to fail again and see what it tells me.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 10,715

    Most power vent water heaters do not have standing pilot ignition with a thermocouple, like the standard chimney vent models.  Your water heater most likely has electronic ignition with some sort of flame detector to prove the flame is established before allowing the main valve to stay open for heating.  The most common flame detector is known as Flame Rectification where the flame must complete a circuit between the burner ground and the flame sensor rod that is hard wired to the ignition control.  You most likely have a dirty flame detecting rod. 

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

    Larry Weingartenmattmia2
  • hunter29
    hunter29 Member Posts: 165

    Right, that's what I was calling a thermocouple, funny I followed the wires into the valve and juggled them and it did not fail when I tried it.

    As soon as I finish cleaning the drain on my furnace I will clean the heater and see if I can get a code.

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 10,715

    You might want to get the instruction manual for the model number of your water heater and review what it says about annual maintenance. HA! annual… right? That should explain the need to keep that electrode wire clean on a regular basis. I'm sure there is a you-tube video on how to do it. Heaven forbid someone pay a pro for that service, and get the combustion analysis that should be completed on each automatic gas burning appliance in your home.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • hunter29
    hunter29 Member Posts: 165

    I reseated the connector again. It's not giving me any problems and the ignition of the gas is quiet now, no more puff back sound if you know what I mean.

    That tells me poor current to the igniter.. ??

    I hadn't realized it got so loud. I still have to take it apart to get access. Then I can clean and inspect.

    It's 11 years old and doing double duty. A few more years would be nice thou..

  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 10,715
    edited July 9

    From your comment(s) it sounds like the ignition module uses one wire to send the spark to light the flame and doubles as the flame sensor once the flame is established. That is very common. Whereas the electrode is engulfed in the flame that it is sensing, (so the electrical current can travel thru the flame) lots of byproducts of combustion and other contaminants that may be floating in the combustion air may from time to time get stuck on the sensor and attach to the sensor. Over time those contaminants can build up and cause a poor electrical connection. Cleaning off the metal flame sensor/ignition rod will restore the electrical circuit. a Scotch-brite pad or some fine steel wool is all you need for that step of the maintenance.

    Edward Young Retired

    After you make that expensive repair and you still have the same problem, What will you check next?

  • mattmia2
    mattmia2 Member Posts: 13,360

    might have to look for the instructions for the ignition control, don't remember mine having much about it in the manual. Mine started doing that soon before it started leaking so i never ended up fixing it.

  • mattmia2
    mattmia2 Member Posts: 13,360

    The burner or pilot burner depending on what system it uses might be dirty so it isn't burning on the flame rod if you were getting delayed ignition.

  • hunter29
    hunter29 Member Posts: 165
    https://forum.heatinghelp.com/discussion/comment/1859793#Comment_1859793

    Three wires…

  • hunter29
    hunter29 Member Posts: 165

    Reseating the connector solved everything. I'm inclined to leave it alone for now. We'll see..

    EdTheHeaterMan

Categories