Yes the temp sensor is the same as the thermistor. Replace it first to clear that error. Once that is cleared and you know you have good flow, cleaned filter etc, you can try and jump out the pressure switch. 9 out of 10 times the LO is the pressure switch. If jumping it out does not clear the error then you need to investigate the limits. There should be two limits inside on the front wall of the unit and one has a small button on it that you can push to reset.
Hayward H350 heater panel not lighting
- Thread starter binyamingavriel
- Start date
Pull the two wires going to the switch and then just connect them together. I use a small wire I have male connectors crimped onto. Sometimes you can just use an alligator clip to connect them.
Still reading LO after connecting. Also backwashed filter to make sure nothing obstructing flow.
So if you bypassed the flow switch and still get the LO reading, then you need to reconnect and start checking the limit switches.
I was able to get a brief temperature readout a couple of times before reverting back to LO. Does that change anything? Thanks
How do I check the limit switches? Or is it just a matter of replacing them and seeing if they now work?
You can use a volt/ohm meter to check if the are open. Also inside the heater are two limits for the fire box. Once has a little reset switch. You can try resetting it.
For some reason this didn't post, so I'll try again. No luck with the volt meter, but when I pressed the manual button the error message cleared and I got a temp display as long as I held it down. Once I released it reverted to LO. I shorted that switch and it stayed on temp reading and tried to ignite (clicking), but after 3 tries the IF code came up.
So that limit is bad. If it's been a while since the heater has run, you might need to let it try to light a few more times. If it still doesn't stay lit, then it would most likely be the ignitor as it is also the flame sensor.
The ignitor is clicking add if trying to light, but I don't see any flame. Is there something else I an supposed to do? My understanding is that there is no pilot light. Is there a way to prime the gas?
When the heater goes to turn on, you should hear a click of the gas valve, sometimes you have to put your hand on it so you can feel the click. Once that happens, it is opening the pilot portion of the valve for a small flow of gas. If the valve isn't doing this, then your heater will not light.
I'm beginning to think you have a lot wrong with the heater and it's going to cost you over $600-$800 to repair it. Is it worth that kind of money to fix it? I would answer that question based upon it's age and how it looks internally. If you are up close to the $800 figure, I would consider a newer unit.
I'm beginning to think you have a lot wrong with the heater and it's going to cost you over $600-$800 to repair it. Is it worth that kind of money to fix it? I would answer that question based upon it's age and how it looks internally. If you are up close to the $800 figure, I would consider a newer unit.
I appreciate the input. Basically I got the unit for free from someone closing their pool. Forgetting installation costs, which would have been the same for new heater, I've put in about $325 in parts. It's frustrating because I feel that with your advice I've gotten very close to having it run, although obviously I can't know for sure until I try and fix the next issue. If it's the ignitor, it's another $40, no big deal. But if I have to replace the gas valve, that's $225, and that's a little more significant. But my total would still be a lot less than a new heater, which I'm seeing for $1800 cheapest for the same model.
Is there a way to check if the gas valve needs to be cleaned out and to do that? I've heard about obstructions due to spider webs, etc., but don't know if that could apply in the valve as well. Also, when the knob on the valve is open, what, if anything, does pushing it in do? Is that a priming mechanism?
Thanks
Is there a way to check if the gas valve needs to be cleaned out and to do that? I've heard about obstructions due to spider webs, etc., but don't know if that could apply in the valve as well. Also, when the knob on the valve is open, what, if anything, does pushing it in do? Is that a priming mechanism?
Thanks
Your heater is an electronic spark ignition so that means the unit itself light a small pilot at the time you turn it on and then lights the rest of the burners. So I'm not sure why you would have a knob on the gas valve that allows you to push it in. That is usually on a unit that has a standing pilot light and not the electronic start. The spider web issues you might be seeing is usually more on the orrifices or burners. Do what I mentioned about listening/feeling the gas valve when you first start it and see what happens. Also see if you smell any gas around the unit when this happens.
It sure doesn't sound like the unit was in good health sold it to you. Good luck and check out the gas valve.
It sure doesn't sound like the unit was in good health sold it to you. Good luck and check out the gas valve.
I couldn't feel a click but I'm not exactly sure where to feel for it. I tested for voltage across the valve (I placed the probes on the two connectors that are towards the rear - brown wires, pic attached), and it stayed at 0 until the ignitor started to click like it was trying to light, at which point the voltage started fluctuating (too fast to read a number) until clicking stopped, then back to 0.
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I just got home and tried cleaning the nozzles with a needle. Started up the heater and after two unsuccessful tries (clicking) the third time I gaff a small fireball shoot out! Then the display went back to IF.
Almost sounds like the gas valve was stuck open. It should click open when the ignitor is clicking and then close if nothing lights. It will do this three times and then give the IF code if the systems doesn't sense a flame.
Seems like it's lighting but not staying lit. Going to do a clean out to see if that helps.
We cleaned it out today. After this it would light for anywhere between 10 and 45 seconds before going out. The ignitor was clicking away the entire time.