Why won't my Hayward H series heater ignite - Hayward Pool & Spa

SOURCE: Problems with Hayward 100,000 Btu Heater

I am sorry to report that this is a very common problem for this heater. Here is more information than you want: http://forum.doityourself.com/pools-spas-hot-tubs/345253-hayward-h100id-ignites-but-cools-quickly.html

Posted on Jun 09, 2009

SOURCE: hayward heater not staying lit

possibly poor pilot adjustment or insuficient mv output from thermopile

Posted on Jun 19, 2009

SOURCE: Hayward H Series 400,000 BTU Pool Heater Won't Ignite

You can not manually light it. Open the front cover look for the gas nozzles brass looking on a tube. on the right side you will see a wire going to a sensor above the next to last burner take the nozzle out for that burner. 7/16 wrench unsrcew the nozzle and see if it is clogged. use something soft to push it out. Spiders love to lay eggs in these. Spray with WD40 and reassemble should work now

Best of luck

Posted on Jun 23, 2009

SOURCE: H Series Pool & Spa Heater 400k Btu Propane Gas Milivolt Ignition H400p1: how do i fix the AO code on my hayward heater?...

AO will apply to your blower, blower tubing, or blower vacuum switch. You need to check these items.

Posted on May 20, 2010

SOURCE: Hayward H-Series 200k BTU Millivolt Heater -

You didn't say what terminals you jumped, but I assume it's the flow switch, or it could be the thermostat. The flow switch is located on the piping inside the heater. This flow switch is very important because if you didn't have water flowing through the heater it would oveheat. These do go bad or sometimes just get stuck depending on what type they are. If it's the thermostat, mounted on the front pane you're jumping, then either it or it's expansion bulb is faulty. GOOD LUCK Who needs a heater in JULY?

Posted on Jul 03, 2010

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