I live in an area where in the summer the average temp is 98. It's starts to get into the 90's in late April and early May. When this happens our hot water heater pilot light goes out. When relit it will work when the temp drops down from the fall through the spring. We have had 3 plumbers come out with no success. They have replaced the thermal-coupler multiple times. The heater is in an attic. Any ideas?

Dirty pilot orifice? Happens. Replacing the thermocouple doesent fix everything.

From another source: "Attic installations are especially problematic. If during the summer months the air that surrounds the water heater is higher than tank's set temperature, the thermostat won't open the gas valve to light the main burner. Heat produced by the pilot flame is not enough to make a condition for natural draft, so all the oxygen will burn up and pilot light will extinguish."

Seems you need to increase the air-flow through the attic and/or reduce the temp up there. If recently installed (last few years), get the original installer back out. They should have been aware of this. Maybe a powered attic exhaust fan or two to reduce that air temp. is in order...

The other option is use an electric H2O tank in the summer.

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The big picture...

http://www.waterheatersforless.com/Tips/...risco-plumbers/

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Thanks guys! This really helps. We'll install an attic fan and see how it goes. Can't believe multiple plumbers didn't know this.