I have a Jandy LT400P-L propane heater that is not working. The control panel has a pressure switch alarm LED flashing. From what I read, this could be from the spa pump not running or a water pressure switch needing reset or replaced. Is there a way to test the switch? Is this a DIY project or should I leave this to a pro? I've also noticed a very faint propane smell. I've had the gas company come out and inspect the tank and its fittings and they were good. I am losing propane and suspect the heater to be the culprit. Is there a particular area in the heater I should have a pro check?