I've run into one of my annual problems getting my old-style Mt. Vernon in working order. Combustion blower runs fine on start up and pellets drop, but the igniter does not glow red. I replaced the igniter with a spare one I happened to have (I've found its useful to have plenty of extra parts on this style), but still get nothing. I've noticed that pressing the reset button does not do anything; it's just soft, not the usual click. The only other thing I can come up with is a bad Snap Disk 1, because the combustion continues to run, but I don't see why that would affect the igniter or the reset button. Any suggestions?