Hayward H250 pilot light won't stay lit.

[erikmpower]

I have recently moved into house with a pool and the previous owner did say that the pool had not been opened in about 2 or 3 years. I have never owned a house with a pool so pools are all new to me.

We just recently had the pool opened and the company that we had open it was trouble shooting the heater to get it to start up. After hours of working on it the technician stated that it needed a new pilot light. I received the estimated invoice for the replacement of the pilot light and it had and hour to replace the pilot light ( that a lot of time to removed two screws and unscrew a gas hose). The technicians returned a few days later to finish checking the pool chemicals (that is another horrible experience with them) and install a new pilot light assembly which had a new thermopile. TWO HOURS later he had the pilot light assembly installed (the slowest worker I have ever seen) but he could not get the burners to come on with out jumping the terminals. He said it needed a new pressure switch and limiter switches. He returned a few days later and 30 minutes into working on the heater he just gave up on working on it and left and did not even attempt to install the new parts.

After reading the manual and researching on the internet I decided to try to fix it myself. First I went through the heater and gave it a good cleaning to get all the stuff out of it and cleaned all of the corrosion off all of the connectors and checked continuity between all the wires to verify that the wires are all good, which they were. After about 15 minutes of holding the gas control knob down and turning it to the on position, I was able to get the pilot light to stay lit. The burners would not come on so I jumped the TH terminals and got the burners to come on. When I removed the jumper the burners would stay lit for a moment or turn off if I turned down the temperature switch. After about 20 minutes the pilot light went out and I could not get it to stay lit. I have held the gas control knob down for up to 5 minutes and measure the thermoplie output and was getting over 500 millivolts. I have attempted this multiple times and got the same results. I have followed the flow chart in the manual and verified that the thermoplie is engulfed by the pilot flame, checked that nothing was blocking the pilot light, and removed both TH wires and attempted to relight the pilot. It would light up but wont stay lit. The next step is to check the thermopile, if below 400mV replace thermopile, if above 500mV it says replace the gas valve. It is reading above 500mV, but I have read on the internet that is even better if a reading is that high. The thermopile is new and getting good readings. But before I pull the trigger of a new gas valve, I wanted to get another opinion from people who have more experience with pool heaters and see if replacing the gas valve is the next correct step to getting the pilot light to stay lit.

I do realize that once I get the pilot light problem fixed that I have another problem of getting the burners to work properly.

Sorry for the long post but I just wanted to state everything that had been done to the heater so far.

Thanks

 

[kimkats]

That is a mighty good write up and sounds like you have done some good in cleaning everything else up. I will tell you this is out of most of the people's skill set here. I am going to say this is something best done by or guided by a licensed gas person BUT not the one that showed up before as you well know. Gas work makes most people nervous.

 

[ps0303]

If you are getting the 500MV at the valve while holding down the gas valve pilot option and upon release of the pilot button it won't stay lit, it would make logical sense that the gas valve is your issue.

 

[danpik]

I would agree with Paul. Time for a new Gas Valve.
Dan

 

[erikmpower]

Thanks for the reply. I have purchased a new gas valve from Amazon and it should be here Thursday. I will post an up date once I install the gas valve.

 

[erikmpower]

Update.

The gas valve came in today and now the pilot light lit right up and stays on when I turn it to the gas control knob to the on position. So my gas valve was faulty. But the burners still do not come on when I turn the unit on and turn the temperature knob up.

The next step in the manual says after jumping the TH terminals to verify that the burners come on is to check the pressure switch. So I checked continuity on the pressure switch connections. I get continuity when the pump is on and has pressure through the heater. No continuity when I turn the pump off. So I know the pressure switch is good. Next step is to check the thermostat. I disconnect the wires from the thermostat knob and jump them and the burner starts up. I checked continuity on the connections of the thermostat and get nothing. I turn the knob back and forth to activate and deactivate the switch and I get no continuity. So I know the thermostat is faulty. Hopefully this is all that is wrong with it and that the heater will work properly after I install a new thermostat.

 

[kimkats]

You will have an almost new heater when you get done but you will have a working heater!!!

Kim

 

[erikmpower]

Almost a new heater and still a lot cheaper than purchasing a new one like the pool technician said I needed to do.

 

[ps0303]

Yeah but over time you would have saved money as this unit burns fuel when the heater isn't even running. The standing pilot burns more than you might think. Plus the new one would have a digital read out of pool temp and error codes as to what it wrong when the heater doesn't start up.

 

[erikmpower]

We just moved into this house and will be closing on it at the end of this month. Our plan is to replace the heater and pump down the road as both units are old. We just want to get at least one or 2 seasons out of it before we do replace it.