I am brand new to the forum today and I am not the most mechanical savy homeowner but I can follow directions.
I have a 28k gal pool with a spa that spills into it and a vanishing edge. We also have solar. Intelliflo pump and Jandy 4 cartridge filter system, Jandy vanishing edge to sheer descents pump, and jandy spa pump. 3/4hp booster pump to get the water up to the roof for solar. Zodiak iAquaLink to control pool with iphone. Polaris Cleaner
We hardly ever use the heater here in the Sacramento foothills and use the Jandy LT 400 maybe 6-10 times a year over the last 10 years that we've had the pool.
When I call for heat, the heater blower kicks on high then drops to a lower speed as it always has, the burners kick on, lots of steam comes out (it's been raining here), and just as (and maybe a split second before) the fan goes back to high speed, the burners kick off. It cycles 3-4 times an then quits trying, with then the Service and Air Flow leds blinking.
I went online and found a Jandy flow chart for troubleshooting. When I measure the voltage o the purple wire going to the pressure switch, I get 28VAC. This of course only when I fire up the heater. The flow chart then says to measue the voltage at the Black/Yellow wire. I'm not sure the proper way to do that. I took it off and it measure 0. When I put it on the spade connection on the back of the pressure switch an stick a meter probe in there, I still get zero. I checked the gray suction tube and it is quite pliable and new looking with no cracks or holes and it has a wire tie fairly securely holding it on at it's non-gauge end.
Am I trouble shooting this correctly? Is the best thing to do to replace the pressure switch. Any thought on other troubleshooting I can do? The air coming out of the exhaust is quite brisk and I found no significant leaves anywhere around the base when I look in the heater with the top off.
Thanks for your time.