Do you know if the burner actually fired off? Meaning you can hear the burner roaring sound and not just the blower running. This is important to know.
Is your battery charged fully? Are you running off of shore power or just battery power?
If you are running off of battery only power, and the battery is not fully charged, the burner can sometimes not fire off as the blower is not running fast enough to activate a sail switch safety when the blower does not runs fast enough. In this case, the blower runs slower then normal, the sail switch never makes contact, the burner never fires off and furnace just plain blows cold air or whatever air temp is in the camper. It's running, but no heat.
We need to know some more about what is or is not working to help better. Try and give us some more to go on.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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