20 Most Recent Raypak 2100 Pool Heater Propane 206000 BTU' (Pilot) () - Page 8 Questions & Answers

You'll have to replace the entire gas valve.

The thermocouple allows the pilot to stay lit. If your burner will not light but the pilot is lit, there is a problem with either the control or the control valve. Either the signal is not being sent to the control valve to open or the signal is being sent and the valve is faulty.

If a 'SPK' Code appears, this indicates that there is power to Igniter and should be producing a Spark to ignite fuel! And then you have ignition and heater heats the water. If this is actually the case, then it is NOT a safety sensor issue, The igniter serves a dual purpose: produce a spark, and then CONFIRM a flame is consuming the fuel. If it does not get a proper Milivolt reading from the flame, Flame Sensor is part of the igniter, then gas valve will shut off, hence a cycle occurs. Not enough reading is the same to the heater as no reading! Safety issue. If gas valve stays open, and no flame to consume raw fuel, it will build up and accumulate then when ignition takes place, it go...BOOM! Not Good. Either insufficient fuel supply/pressure or faulty igniter. It's also not a Gas Valve. It's a simple switching valve, either open or closed.

thermistor problem

I'm having that same problem and I don't know what to do. I hate not having a nice warm pool. It makes me not want to invite people over. http://poolsolarwa.com/gas-pool-heating/

check the ohms value with it disconnected

if new heater and wired 120 volt try changing the black and white wires might not be reading rectification if old heater could be flame sensor

check your gas pressure if not correct it will soot up overheating as a result

it is located on the header side where pipes go in unscrew it and check to see if the spring is ok and functional

need a new fuseable link but why did it overheat check gas pressure if sooted up clean heat exchange or if ok need a wind stack