Hayward H100i Spa Heater


New member
Dec 5, 2014
West Melbourne FL
I have a Hayward H100i 100,000 BTU propane spa heater. I recently had to replace the blower because the original fan blades had rusted off. The new blower runs fine and the heater heats the spa water. However, the heater runs for only a few minutes before shutting down and it feels very hot to the touch. After a cool down period the heater will start on it own and the cycle repeats. I suspect that the blower thermal switch may not be functioning properly because the blower seems to run at high speed all the time.

Can anyone shed some light on what the problem may be?