Limit switch trips on Atwood furnace

[LDMontgom]

My 1993 Jayco Motorhome Atwood furnace fan runs for @ 12-15 sec then the furnace ignites, it runs for a sec or two, then the limit switch trips.

[LDMontgom]

I forgot to mention that this started after I replaced the blower motor that was locked up.
All vents and return are clear.
I had thought about replacing the sail switch, but I didn’t just want to start replacing parts and throwing away money.

[BFL13]

Return air vent plugged up, or heat ducts plugged up,(dog hair?) or outlet vents closed in some rooms (open them all)

Remove floor and wall registers to vacuum the ducts out, remove return air vent to vacuum behind it.

It might not be the limit switch, but the flame sensor might not be detecting the flame. Check the prongs in the burner for stuff on them.

[pushtoy_2]

not enough air flow. Voltage low or sail switch badbad