20 Most Recent Hayward H Series Pool & Spa Heater 400k Btu Propane Gas Milivolt Ignition H400p1 Questions & Answers

yes, make sure you order the correct part, youll need the model number and serial number. the ignitor has 2 wires wrapped with white fibers, usually 2 screws to remove it, and theres only one way to plug it back in. NOTE: Ignition failure does not always mean the ignitor needs replaced. make sure your ignitor doesnt turn on and glow when you start the heater. if it does, youll want to clean out the gas orifices.

Hayward H Series... | Answered on Sep 06, 2020

Thank you for posting your question here on Fixya.com.

You will need a monometer to check gas pressure before and after the valve and a voltmeter to check for voltage at the valve.

Hook up the monometer and watch for pressure drop during the ignition phase. If it does and the heater won't light your problem is in the ignitor or control board. If it does not your problem is the board or the valve.

Check for voltage at the gas valve to confirm if the valve or the board is the problem.

If you are unfamiliar with these tools you should call a professional. You are working in a potentially dangerous environment.

If this answer does not fix your problem, please comment with additional details prior to rating the answer. Positive feedback is appreciated once your problem is solved!

Hayward H Series... | Answered on Nov 23, 2017

This is a normal display when heater is being controlled by a remote thermostat. No service is required. If heater is not being controlled by remote thermostat, change setting by using the MODE key to put the heater into STANDBY. Press and hold the DOWN key and then press and hold the MODE key. HOLD down both keys for 3 seconds until the indication "bo" is removed from the display.
The key to this is DOWN first and then together with MODE, both for 3 seconds.

Make sure the display is not showing "BD".

Hayward H Series... | Answered on Jul 07, 2017

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 Buick..so 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.

Hayward H Series... | Answered on Apr 27, 2017

error codes don't appear on millivolt units. LO for digital models is an open safety within circuit, most common being the pressure switch

Hayward H Series... | Answered on May 29, 2016

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