I live 50 miles from the nearest pool repair tech and therefore try to fix everything I can on my own before paying for an expensive travel visit. I posted on here about 2 years ago and you guys were able to help me troubleshoot a bad temperature sensor and save me a ton of $$$. Everything has been working fine until about a week ago. I heated the hot tub and even heated the pool up a few degrees on Memorial day, but I shut the heater off was just cycling the filter pump and waterslide and waterfalls later on in the afternoon when I noticed that day one of my chlorinator hoses sprung a leak. I had to shut all the pumps off and replace the hose. When I went to turn the heater back on the next day (I think), the control panel inside seemed to indicate that it was heating but the water temp was not riding. Further inspection revealed that the actual heater is displaying a "service heater" night and not heating at all. The actual heater box has 3 buttons - "spa on", "pool on", and "heater off". If I push the "pool on" button, it lights up and the "service heater" light goes off, but still the heater does not actually turn on. As soon as I hit "spa on" the servie heater light comes back on. I have tried powering off the entire system at the breaker box, resetting the system, etc. No luck. There is a panel inside the heater box that will sometimes (depending on what buttons I have pushed) flash one red LED light and per the display that seems to indicate an "air flow fault". I have no idea what this means. I managed to catch a picture when the light flashed so you could see it. My heater is pilotless so there should be no pilot light to re-light. I have plenty of propane in my tank and the valves are all still on all the way to the heater. There are no error messages displayed on the control display in the house or in the control box at the pump area. There is an on/off switch on the ignitor box inside the heater; I shut it off with the electronics powered off for 5 minutes, turned it back on for 5 minutes, then re-powered the system on hoping that would re-ignite something, but no change. Where else should I start?