Suburban NT-30 not igniting

[adwriter73]

Furnace is only 2 years old. Blower comes on, but it's not igniting. Just shuts off. I pulled off the front cover. Don't really see what I should be checking. Owner's manual doesn't offer much help.

[idroba]

Simple things first. Are you sure you have gas? Turn the range on to check that. Also check that the gas valve for the furnace is on. Next would be to be sure the battery voltage is high enough. Is the rig plugged into shore power so you know the battery is charged and the converter/charger is working? Low voltage can cause the furnace to not ignite.

From there, it is stuff like mud dauber nests in the intake/exhaust, the electric gas valve not opening (rare for a 2 year old furnace) and of course a bad ignition module or contacts where things plug into the module.

Those are some places to start anyway.

[adwriter73]

Gas - Check! Propane tank is full.
Voltage - Check! I'm plugged into 30-amp shore power.
Intake/exhaust - Clear!

Must be the gas valve or ignition module. Sounds like I need to remove it and check it out.

[tkasten]

Is it making a clicking sound? (Will do that 3 times trying to light). Could be a bad limit switch or sail switch. Have you tried banging on the side of the furnace? Sometimes switches stick. If it does light after banging on the side then you probably need a new sail switch.

[adwriter73]

Originally Posted by tkasten

Is it making a clicking sound? (Will do that 3 times trying to light). Could be a bad limit switch or sail switch. Have you tried banging on the side of the furnace? Sometimes switches stick. If it does light after banging on the side then you probably need a new sail switch.

Nope. Not clicking like it usually does. Just the blower. I tried banging on it, too. Didn't do anything. Might try to spray some canned air on the components to see what that will do.