Sealed Water Heater; Pilot lights outside, not inside.

[Robert S.]

Hello, we have a hot water tank from 2004, a sealed combustion type from GE. Recently our basement flooded which knocked out the pilot. When trying to relight the pilot I could see the spark from the little view window but alas no flame. I uninstalled the combustion unit to check inside and do general maintenance, cleaning the thermopile, igniter and pilot tube. For grins I hooked the igniter and pilot back up while the unit was sitting on the concrete floor to test, and the pilot lit with one spark and looked very healthy. Thinking all it needed was a good cleaning, I reinstalled everything but the pilot still will not light while in the unit. The only thing I can think of is that there isn't enough air in the chamber to get a flame.

I removed everything again and checked the TDR "latch?" in the tank and it is still intact, I can see the glass vial is in one piece. My question is this... I noticed that there was still water seeping from the insulation that surrounds the inside of the tank between the tank and the void where I assume the airflow would come from. Is that most likely what is cutting off the air so the pilot won't light? It's strange because last year our basement REALLY flooded (like 20 inches of water) and the hot water tank never lost flame, this time the flood was a mere 4 inches and all hell broke lose.

I'm totally at a lose, I've done plenty of repairs on other water heaters but this is my first dance with a sealed design and I really would hate to pay for a plumber to come out to tell me to let it air out for a couple more days because there is nothing more they can do. Any advice would greatly be appreciated. Thank you.

 

[Breplum]

Some WH models have a baffle that is spring loaded on the bottom air intake. If the baffle tripped then the combustion air source is closed.
You would have seen this inside, though, when you removed the burner assy.
Take the observation window out and try to ignite it conventionally and get the window back into place if it does ignite, as best you can.

 

[Sponsor]

 

[Bannerman]

Are you certain it is actually a standing 'pilot light' that you need to manually light

With a sealed combustion chamber, I would not expect a standing pilot light to be utilized. Perhaps during each ignition sequence, the burner control will activate the igniter which will then ignite the main burner.

 

[Robert S.]

Bannerman: Very certain it is not an automated pilot. The pilot light instructions pretty much read, red button to activate the solenoid while the gas control is set to pilot. Then press on the red plunger to get spark from the igniter. After pilot is lit, keeping holding down red solenoid for a minute.. etc etc. I've had to relight this before when our gas was turned off due to street construction.

breplum: I tried to gently remove the window, even just to see if the sudden exposure to fresh O2 would solve my problem, but I was getting concerned that I was on the verge of breaking it, and from what I've been told if anything is done to compromise the expected air flow inside the chamber then the TDR latch as you mentioned would surely trip IF I ever got t he burner to light and heat up... so I backed out.

Update: Day 3 and still no flame. Everything is still soaking wet even after having a high volume fan blow on the area for over 12 hours. I'm starting to think that maybe there is a small crack in the tank that is letting water seep slowly but surely. Also wondering if a service tech is worth it or if I should just start looking into getting a new water heater.

 

[Fitter30]

20" of water is that over the gas valve? Read this
https://www.allplumbing247.com/weba...-it-safe-to-use-my-flood-damaged-water-heater

 

[Robert S.]

Thank you fitter for the link. I'm starting to seriously consider just replacing the unit, especially after that read. No the water never rose above the gas valve, but the bottom of the tank up to the valve was swimming, hence my astonishment that the pilot didn't go out that day, no fail safe tripped, nothing... which in itself may be cause for alarm. This thing is starting to defy all logic, I'm just trying to avoid a hefty bill at the end of the day just to enjoy a hot shower.

 

[Dj2]

You are lucky the flood happened to a WH from 2004 and not a new one.
Just replace the WH, it's time.
Good news: prices of gas WHs went down a little bit, at least in my state, so take advantage of this TPR (temporary price reduction).

 

[Master Plumber Mark]

your water heater is a 2004,,,, that makes it like pushing 18 years old

just look into a new unit

 

[MACPLUMB]

GET A NEW WATER HEATER ! AND BE DONE WITH IT