Could it be a defective pressure switch? they tend to go awry due to corrosion from the pool water. It is relatively easy and inexpensive piece to replace. My pool guy gave me a good suggestion. Fill the end that connects to the water line with a little mineral oil. That keeps water from reaching the mechanical diaphram that senses the pressure.

We just bought a new gas heater, but our old one was alomst 30 years old. Bought a Hayward draft induced heater. It was easy to connect and started right up and so far works wonderfully. I think the biggest problem with heaters is exposure of the electronics to the elements. I am thinking of making a ventilated enclosure for it when we no longer need it for the season and winter.

The problem with heat pumps in colder climates is that they are not very efficient if the air temp is below 60 degrees, e.g. spring when one needs the heater the most.


Hal