Critt, did you do the test like I suggested in post 10? I still think your regulator is not flowing enough to support flame in the heater but may be able to support just the stove. You never posted the results so I assume it was never performed.
Again, allow the heater to run while you watch the burner on the stove. If the flame on the stove starts turning yellow and dies down followed by the furnace not putting out heat, I'd suspect a bad or misadjusted regulator. Some have an adjustable setting.
*Current: 2005 Ford F350 Crew Cab Dually 6.0 diesel 4x4*
*Retired: 1987 F350 Crew Cab Dually 6.9 turbo diesel
2007 Forest River WildCat 32QBBS