Inside the heater should be a black rectangular gel coated square box with wires plugged into it. On that box is a small red led. Is the LED on? (pilot should be lit to check)
Also, If u remove the black wire from the gas valve that's connected to TH on the gas valve and then jump the TH to the PP( pool pump), do the burners come on?.Make sure that when you do this that the pool pump is running and water is going through the heater, because you are bypassing the heaters controls to test the gas valve for operation.
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IF this is what happens:----
Had to hold pilot buttom down to keep pilot lit. held it down and no LED. While holding pilot down removed black wire from TH and jumped to PP, burner did NOT lite.
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Did you leave the pilot wires connected to the valve? Remove the black from the TH position and tighten the screw back down then relight the pilot. It should be able to relight without an issue. The thermopile(pilot generator) has to be connected. Once you get the pilot to stay lit, then jump those 2 terminals. Make sure that the yellow wire that goes from the PP/TH terminal is connected to the gas valve and make sure the connection is clean. The wire nut, make sure thats not corroded under there. A low pilot flame can also be doing this, so you want to make sure the pilot orifice isn't clogged. Do you have an electrical tester that can test millivolts?
OK, if millivolts test more then 500 or 600 then its good thermocouple.
If youre getting 620MV and the pilot wont stay lit then the gas valve is bad. -
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Still try remove and clean the pilot assembly, Also, how is your gas pressure? Low gas pressure can cause the pilot to be low. Its possible you have a defective part there.
There is no pilot flame adjustment from down there, before you do anything else, take a small needle and clean out the orifice. The outside of the pilot may look clean but the actual hole that the gas goes through is actually tiny. tiny enough that a single grain of sand can clog it. The model you list i believe is a natural gas unit. before any adjustments are made to the valve itself, its crucial to know what gas pressure is going into the valve. To clean the orifice your going to have to remove the pilot tube from the pilot assembly and use a pin to clean from the back side. Right now, with what i can read at this time, its pointing to a bad gas valve.
