With your question, I will assume all other propane fired devices worked normally (stove, refrigerator, water heater...).
Thermostat set, switch to 'On' fan on 'low', 'high' etc. Heater fans kicked on but the burner did not fire.
With that said, check the intake and exhaust ports on the outside to make sure they are unobstructed. (spider webs, rodent nests.... )
Remove the cover from the heater unit and inspect the ignitor and burner area. Use some canned air or a air hose and clean the area. Test the system. If it still doesn't work look to electrical issue. Power at the ignitor?
2015 White Hawk 25BHS Glacier Package
2004 Dodge Ram 2500, 5.7 Hemi, 5Spd Manual
2008 Arctic Cat M1000 SnoPro
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