Can't seem to get honeywell s8610u replacement module to work. Original module was S8600. Installed as called for in instructions and will not ignite, but gas is present.Checked grounds etc. all OK. Removed module off second unit and installed on broken unit and it works good.

Need more info. Furnace model and make.
Info on old moudel what wire went to what and where did you put them to new one.what s8610u**** did you get.

Raypak M#W2-o624c-
S8610U3009- replacing S8600H1005.
Replaced wire for wire on new as they were on old. Also tryied putting on twh instaed of 24v supply as book asked.Still no ignition.