I have a GSW series 6 hot water tank model# G640S34FV-04. Thermalcouple part # needed

SOURCE: I dont have hot water after i change the thermalcouple

diaphrapm valve or micro switch

SOURCE: Water is pouring steaming hot water from a copper

Sounds like the TP valve is releasing water.
http://waterheatertimer.org/Water-heater-leaking.html

To protect your property right now, turn off water heater:
Gas: turn gas valve to pilot so pilot light stays lit but burner will not turn on.
Electric: flip circuit breaker off

Next turn off water valve located on cold water line above water heater.
Last, open tub faucet to relieve pressure on tank.
Once pressure is off after a few moments, close tub valve.

The question is why is the TP valve releasing water.

1) Stuck TP valve: raise lever on TP valve and let back down slowly

2) bad TP valve: replace TP using same temp-pressure rating available from hardware store. Wrap teflon tape around threads and screw new TP valve clockwise until very tight. Make sure water is cool before removing valve from water heater. If you take out valve when water heater is hot, it will spew scalding water all over you. This is serious. Let the water cool down for several hours.

3) Runaway heating caused by bad thermostat
Gas: buy replacement valve at Lowes or plumbing store and replace according to instructions.
Electric: several causes. Test parts to determine which needs replacement.
http://waterheatertimer.org/How-to-troubleshoot-electric-problems-with-water-heater.html


More support:

a) Fixya offers phone support where you speak with a fixya expert on telephone for a fee.
You can use this service if you hit a trouble spot when repairing your tank.

b) You can also call a plumber who will know exactly what to do.

c) You can post questions at a professional plumbing forum:
http://www.thetankatwaterheaterrescue.com/forums/forum3/

SOURCE: we replaced our hot water tank a month ago and now

Water pressure is blowing everyting loose with new heater,give your system a good flush,it will work it self out. RichieRich

SOURCE: WATER HEATER GOES OUT OVER NIGHT

you either have a back draft blowing out the pilot light, or a bad thermal coupling. if coupling is bad it will shut down the gas flow therefore shutting off pilot light. its a safety measure to stop the gas flow if pilot goes out. replace thermal coupling, that may do it. good-day ! but shut off gas first !

SOURCE: i have a mor-flo model # e52-38l-038d serie

I know that every model has different ways to reset them. I would just start my search online. You can try to find a parts diagram that will show you where the reset switch is. Have you tried to look down by the pilot light? That's where mine is. http://aceplumbing.com/water-heaters

Water Heaters

aceplumbing.com

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