Question about Hayward H Series Pool & Spa Heater 400k Btu Propane Gas Milivolt Ignition H400p1

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I have a hayward H400 serise propane heater. I replaced the gas valve. When it goes tot turn on it takes about a minute then starts clicking to ingnite the gas. SSoem time it lights but then goes out other times it does not light. Each time it takes about 1 minute before it tries to light (click). Any idea what could be the issue?

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0. Check the spark ignitor conection to the board
1. Check the water by-pass valve if you have it
2. Check your gas pressure. (5-7"wc for natural gas, 9-13"wc for propane gas)
3. Clean your filter for your water system or remove it and try again
4. Check the Hi-limits on your heater
5. Replace the thermostat

Posted on May 29, 2010


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Is this a millivolt or electric ignition heater? You can tell by the connections: gas only = millivolt, gas + electrical conduit = electric ignition.
Sometimes people ridicule us for asking the obvious, but I thought this would be helpful: 1) Are your operating the heater with the pump running? 2) Is the gas to the heater turned on; either at the propane valve (is there propane in the tanks?) or is the valve at the meter for natural gas in the on position.
is the code for ignition failure on Hayward Heaters. This could be related to a bad igniter or plugged burner orifices. Failure often indicates that the sensor wire to the ignitor is bad, rather than the ignitor itself. Inspect this wire, and if the sheathing is cracked or worn, replace it.

If the gas pressure and supply is OK, the proper order for parts replacement would be:
Sensor wire, then the ignitor, then the gas valve.
To inspect the igniter for operation, remove the igniter and turn the heater on and watch for a spark (don't hold it, you'll get zapped!). If you don't see one, try adjusting the spark generator relative to the metal ground around it. Clean out the area where it mounts as best you can.
We have serviced similar issues several times where spiders or debris actually kept the spark from reaching the gas.
Check here for manual and diagrams on all Hayward products

I hope that this helps! Please take a moment to give us feedback on the information that has been provided. We all volunteer our time and expertise to help you all out and th biggest compliment is the referral of your friends to the website and feedback from you!
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Gas valve.
Gas valves will often stick in the closed position especially after sitting dormant for a period of time.
if you want the posibility of one more season, You can try to tap on the bottom ans side of the valve with handle of a screw driver while it tries to ignite. Note: This is a technician trick, most manufacturers will not approve in fear you are so lacking in common sense you will go out and beat the valve with a hammer, then sue them when it cracks the metal valve leaking gas while you smoke a cigar ultimately relocating your heater on top of the neighbors please don't do that. BUT, If the valve opens and heater fires with a few love taps try it a couple more times to see if it will work on its own. It will likely continue to work if so.
You will likely need that gas valve next year anyway.

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