I have a Hayward h250 that will only fire up by jumping the white and red wires near the front valve for a sec. It worked again this year. Once. Now when i Touch the white to red I head a click and the pilot goes out. Any Ideas? Thanks.
Hayward H250 heater
- Thread starter mak104
- Start date
By jumpering the red to the white on the gas valve you were effectively bypassing all of the safety switches in the system. It may have worked as there may be some corrosion that was "eating" up the voltage signal to power the valve. This was happening because the powerpile may be getting weak. You need to get a volt/ohm meter on the red and white wires to see what millivolt reading you get. Ideally you should see 750 Mv. Anything below ~450 probably will not allow the unit to fire. The powerpile most likely needs to be replaced. You also need to see if the pilot flame is burning properly and is engulfing the powerpile completely.
No I haven't. It makes an audible click when I attempt to jump it. I have the thermopile unit removed. Would ordering a new one be prudent?
hook it back up and close the access door and let it try and fire. Its sounds crazy but when I got my new H250 2 weeks ago I had the same issue with the access door open. I closed it and it fired right up.
I hooked it back up after checking to see that the pilot burners holes were clear and blew the tube out with compressed air. Put the door on. Still nothing. It still clicks and the pilot goes out when I attempt to jump it.
If you're truly jumping the red wire and the white wire on the thermopile, you're shorting it thus causing it to shut of the gas flow for the pilot. Have you measured the mv that the thermopile is generating?
Yes. 500. And momentarily jumping those two wires has caused the heater to fire up in the past.
You need to jump the TH/TP to the TH it should lite. Jumping across the red and white wires of the thermopile will short it and cause the valve to close the pilot portion. Here is an older post that has a great graphic from another tech. Time for a new gas valve, or time for a new heater?
Also, while measuring the voltage across the red and white wires, if you turn the heaters switch to the on position, now what is your voltage?
Also, while measuring the voltage across the red and white wires, if you turn the heaters switch to the on position, now what is your voltage?
Here is the image Paul spoke of. I did not look up the wiring schematic and did not ever register in my head that you jumped the red and white wires. Those are usually/always the powerpile lead colors. As Paul mentioned, you need to check the voltage there both at idle and with the unit on to get a voltage reading. On the below diagram the "d" and "e" terminals will have the Red and White wires
You also need to check the voltage reading thru the whole system with a "call for heat" to see where the voltage drops to.
"d" and "e" will give you the powerpile output, "e" and "f" will give you the voltage thru the system. My bet is "e" and "f" will not give you the 500 mv you are seeing from the powerpile
To test for a possible bad safety switch, you can temporarily jump between "d" and "f" on the below schematic. If the unit lights then you either have a bad safety switch or a weak thermopile (or possibly a lot of corrosion on some connections in the circuit). To test the safeties you need to use a volt/ohm meter and check the voltage thru each switch when in a "call for heat" mode
You also need to check the voltage reading thru the whole system with a "call for heat" to see where the voltage drops to.
"d" and "e" will give you the powerpile output, "e" and "f" will give you the voltage thru the system. My bet is "e" and "f" will not give you the 500 mv you are seeing from the powerpile
To test for a possible bad safety switch, you can temporarily jump between "d" and "f" on the below schematic. If the unit lights then you either have a bad safety switch or a weak thermopile (or possibly a lot of corrosion on some connections in the circuit). To test the safeties you need to use a volt/ohm meter and check the voltage thru each switch when in a "call for heat" mode
I said that iI was jumping d and e earlier and it was firing up. Obviously I was mistaken. As you say Danpik,jumping d and f is what gets it fired up. It still does this. I'm getting a reading of 60 between th and tp WITH THE UNIT RUNNING.Can the safety switches be tested with it running? And wouldn't you have to know if the switches are normally open or normally closed? Thanks again for all the help.
So what do you measure across d and e when you push the on switch? If you drop way below 400, then you have a safety that is causing the issue of it not firing. What you can do is jump each safety one at a time to see which one is the cause of the issue. I usually start with jumping the on/off switch. I find many of these bad. If no fire, then put it back the way it was and jump the roll out switch, and so on right down the line.
Order of items I find wrong, on/off switch, rollout switch, one or both high limit switches.
Order of items I find wrong, on/off switch, rollout switch, one or both high limit switches.
Sorry for the delay.I've been working 12 hour shifts.I tried jumping the on/off and the 3 safety switches.It didn't make it fire. Thermopile?
I re read your posts and you say you have 500mv across the red and white wires while the flame is present. If so, then your thermopile is good. If you were less than 400, then I might suspect it. 500mv is very strong and good.
There is also the possibility that the thermostat or thermostat controls are bad.
What is the exact model of this unit? How about posting a picture of it?
There is also the possibility that the thermostat or thermostat controls are bad.
What is the exact model of this unit? How about posting a picture of it?
OK so what you need to do is start tracing the entire safety circuit to see where you are losing power. If you have 500mv at the valve, you should be able to follow that thru the entire safety loop until you find where it drops out, then that is your issue. Follow danpik's post above and you can traverse thru the safety loop. If you don't find a drop out in the safety, then it's probably the thermostat control.
Ok. I'm hosting my grandson's graduation party on Sat.,So I might not respond for a couple of days. Busier than ****.I'll do the tests as soon as I can. Thanks ps. Just FTR, my pool is 44,000 gallons. I have a pentair chlorine feeder (300) that doesn't inject enough chlorine to keep my level up with the cheap test kit.I ordered another feeder. I figured two might do it. Then I started reading here. I cancelled the extra feeder, ordered up a Taylor test kit and 24 gallons of liquid chlorine.And became a site supporter. I've had this pool for 15 years and most times ll is well. But when algae strikes it's relentless.This is a great place to learn the proper method of pool care. Thanks again.
