ignition lockout error

I have been trying to get my Jandy LXI 400 (propane) working for the last year and a half and still no luck. Here is the latest: Blower comes on, I hear the 3 clicks, I smell propane, nothing ignites, get “Ignition Lockout” error. So far I have: 1) replaced flame sensor 2) replaced ignighter 3)...