It's been a little touchy lately, but now when I turn on the heater, I just get a click at 5 seconds, and a faint smell of gas. My guess is that the igniter is not working. I don't remember if it should click frequently to ignite, but it isn't. When I turn it on, it says RP 22, then 5 seconds later it clicks, and says SPK 22.

I'm thinking the RP is Raypak, and the SPK is spark, and maybe the 22 is a code?