Nt-20SEQ Furnace not working correctly

The “electrode” (which I think you are calling an “igniter”) not only ignites the burner but also detects the burner flame. It sounds like this may be the problem. It may be defective or not properly positioned in the flame. Another possibility is the flame is not burning properly.

try blowing compressed air through the exhaust system and see if anything comes out.  thats the issue I had with my camper furnace and it was bugs in the exhaust and combustion chamber.  

Is this also your Topic under another user name?

Re: Salem Cruise lite RV furnace - Good Sam Community - 3682130

Try the suggestions in that thread. Bad thermocouple, regulator or debris in the exhaust vent would be my guess. And how did you buy an RV less than a year old with no factory warranty?

Here is the original video of what the furnace was doing.   I decided to take the unit completely out last night and do some bench tests.   I removed from housing, put on my workbench, connected propane, connected to 12vs, touched the two blue thermostat wires together and the furnace ran beautifully. So my thought since it ran fine on my workbench that my thermostat in the camper was the issue.   I reinstalled furnace, connected to the thermostat to call for heat.  Same non working results in video.  Disconnected thermostat and connected the two blue wires together and works like a champ!  So my issue is my campers thermostat.  Have a new one on order.   Thanks for all the comments and suggestions.