Honeywell S8600F replacement issues


New member
Apr 2, 2016
San Clemente
I was having problems with my pool heater so I opened it up and noticed that many of the wires had melted and the ignition control module cover was melted as well. I grabbed my multi meter and tried to find the reason my heater was not coming on but decided I should replace the wire harness and the control module while I was in there (it is 14 years old and melting so why not).

I ordered a Honeywell S8610U which should be a direct replacement for my S8600F but after replacing all the wires and installing the new control unit I am not getting any spark and the PV light on my control board is not lit. The strange thing is that if I hook up my old S8600F everything works just fine, when I install the S8610U I get nothing. There is no LED status indicator flashing on the new unit, nothing and no PV light on the board. Hook up the old, melted unit and all is well.

I really would like to replace the old one since I know it will fail sooner or later but cannot get the new one to I missing something?


old unit:


Pool Clown

In The Industry
Sep 5, 2008
Silicon Valley, CA
When you are replacing one spark box for another (different numbers) the wire lineup may not always be in the same order. Make sure that you are transferring the wires by their name and not the order. If there is any documentation either in the box, or something you can get off the net get it, and read up. Even i must do this as old boxes are more and more becoming replaced by new boxes, and i can confirm that they don't always wire up the same as the old ones.

MV, MV/PV, and PV should all go to the gas valve. Spark should disappear under the burner tray. Both the 24V should go to either the power on the board or to the x-former.

Also, maybe most important, confirm that your new box is for the same "kind" of ignition. Either a spark gap ignition, or a hot surface ignition. One wont work on the other, and may ruin parts, ie. the pilot assembly, maybe even your brand new box!