Rheem Raypak igniter failure.


New member
Aug 28, 2019
Minneapolis, MN
I have a Rheem pool heater. The ignition does not work. It is an IID, intermittent ignition device. I have replaced the igniter. However, I fear it is the control board. What voltage should I see on the power lead to the igniter coming from the control board? My transformer is providing 24 V to the control board. And the control board does show CFH (call for heat) and SPK (spark). However, I don't see any voltage going to the igniter?


TFP Guide
In The Industry
Apr 5, 2015
tucson, arizona
There's no way to measure a voltage on this wire I'm aware of. What is recommended is with a pair of insulated needle nose pliers pull the ignition wire off board and hold next to that connection and start ignition sequence. If you see a spark board is okay. If not you should replace PC board


TFP Expert
Mar 2, 2011
The electronic spark generator in the module produces a high-voltage spark pulse output (about 20,000 volts) that lights the pilot burner.

If you're not getting a spark, the board could be bad.

What exact model do you have?

How old is the heater?

Here are some videos that show how the ignition control works.

Last edited:

Pool Clown

In The Industry
Sep 5, 2008
Silicon Valley, CA
The Rheem (Raypak) heaters have the ignition control integrated onto the main board. That video may be a bit confusing. Make sure the blue wire from the board to the pilot assembly is good (not chewed) and the pilot bracket has a good and tight connection to the frame. You may have a ground wire that is connected to that screw on the pilot bracket. When you are trying to fire the heater, do you hear any buzzing? How about the display, what does the display...display? Does it time out and stop trying to light?


TFP Guide
Jun 4, 2012
western NY
On the board, there will be a black circular object about 1/25" dia and about the same height. This will have a heavy wire coming from the top of it. This is the spark coil that sends the high voltage spark down the wire to the igniter. Check the back side of the board to see if one of the solder connections is bad (visible crack around the terminal) If you can find an electronics guy in your area he can re-solder that connection. I had to do this on a similar board earlier this year and a couple last year. The RoHS compliant solder is not as good as the old Lead based stuff and doesn't hold up as well.