Suburban furnace quit working (again)

[GinjaTurtle]

Hi Everyone.

 

I have a suburban NT-16 furnace in my 1988 Toyota Odyssey. Back in 2019 I was having issues where the fan would start, but the ignition sequence never happens. To resolve it back then I bought a replacement board from ebay like this one: https://www.ebay.com/itm/386313082243?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=n-ju0w2ptyy&sssrc=2047675&ssuid=1-1GOiu-Twm&widget_ver=artemis&media=COPY. It solved the issue for me at the time, but the issue has returned.

 

I've done some troubleshooting steps including:

-Test the propane supply by replacing the regulator

-Bypass the propane plumbing by connecting the tank/regulator directly to the inlet on the heater

-Test sail switch with continuity tester (good)

-Test resistance over both propane valves (40-45 ohm, good)

-Check for voltage to the control board (good)

-Check for voltage at the propane valves 30+ seconds after fan start (no voltage)

 

I think this isolates the problem to the board.

 

Does anyone have experience with these? Are the newer boards unreliable? Should I buy another one or potentially a Dinosaur control board (https://www.dinosaurelectronics.com/UIB_S.htm)? Should I bail on the whole thing and replace the whole furnace (either with another NT-16 or maybe something else???)?

 

Thanks for being a great group.

 

 

Edited November 7, 2024 by GinjaTurtle

[fred heath]

Dinosaur boards are good quality. One nice feature is they will attempt to light the furnace 3 times before shutting down. Rather then once like the factory board.

 

 

[mattrblack50@gmail.com]

I had an issue like this before. Bought a new board and took the furnace apart too. If I remember correctly it was the small thermocouple / temp sensor that was causing issues. It was good but the spade connections were dirty / crusty. Cleaned them and no issues. 

 

It would turn on the fan and try and light 3 times but no ignition because of the thermocouple.