Pool heater won't ignite ...


New member
Apr 14, 2017
I have a rheem M407 pool heater. It has electronic ignition and controls.


Last season worked fine. This season - won't fire up.

The controls all seem normal. the temperauture is set above pool temp. The "spark" is showing on the LED panel and I can hear the igniter clicking (sparks?).
I can smell a faint whiff of gas from the pilot tube after I set the unit to call for heat. but no ignition. No error codes either.

Before I call someone, I thought I'd run the problem by this forum in the hope that someone experienced what I am experiencing and can suggest a few more options.

As far as I can tell - nothing is wrong (gas valve is on).



Gold Supporter
Aug 13, 2015
Frisco, Texas
I had similar issues. We (me and my PB) narrowed it down to a overly sensitive flow meter. So when I heat my pool now, I just make sure to bump up the pump's RPM's to increase the flow rate.

BTW, my heater is a Pentair heater and I found a really useful troubleshooting flowchart in the back of the user manual for it.