Hayward H Series Heater Won't Turn Off

[coilerman]

I have a Hayward H series pool and spa gas heater and it started up just fine this spring but now it doesn't seem to turn off and will not change modes. When I turn off the power button, it just stays on. The Pool button is lit. When I try to put it into Standby, the mode button has no effect. I know I was able to put it in Standby when I started up the heater a few weeks ago. But now, nothing. To turn off the heater, I have to flip the circuit breaker. Any thoughts on what may be wrong?

[txpoolguy]

Most likely the keypad has failed. If it won't switch modes, this is the most likely issue. However, this would prevent the heater from firing, even if the "pool" button is still lit.

When you say "the heater won't turn off", do the burners actually stay lit until you turn off the breaker??? This would be extremely rare, and would be cause for concern. You should turn the gas off to the heater to eliminate any possibility of it turning on, and call an authorized servicer immediately.

You find Hayward authorized servicers by going to www.haywardnet.com, select "locator" and search by your zip code for an authorized servicer. Be sure to select which product you're inquiring about. This will list all authorized servicers by proximity to you.

[Jerry Fanelli]

MY 2004 MILLIVOLT NON DIGITAL GAS HEATER WILL HOT TURN OFF WHEN THE PUMP IS TURNED OFF. I REPLACED THE PRESSURE SWITCH AND MY 3 LIMIT SWITCHES ARE GOOD. IT WILL CYCLE ON AND OFF WITH THE ON/OFF SWITCH AND WILL CYCLE ON AND OFF WITH THE THERMOSTSAT, BUT WILL NOT CYCLE  OFF WHEN THE PUMP IS TURNED OFF.