What heater part am i missing?

A quick google shows the 30k BTU version of the SuburbanNT to be in the $400 range.

That's like buying a couple of batteries ;)

If you have the money, it's a once and you're SURE you are done and safe. You've replaced the whole thing :C

I agree this is the best option if you can- especially since you don't know who did what or why to it (or other parts of it that you don't see?)

Good luck!

Good call. You can replace it with a new SuburbanNT series easily, the new one will need a small platform to line up with the exhaust vent holes, which is easy to do.

based on my limited knowledgeof these heaters and the cost of having a local shop look at it compared to getting another one i think its a safer bet to get a new one. I wouldnt feel safe with the kids in it knowing that someone monkeyed with it. The lady o bought it from claimed it worked great but of course i wasnt able to test it and took her at her word. Oh well live and learn....

The guts slide out the front of the case, after disconnecting the gas and wiring. I don't know where the limit switch came from, the limit switch is not in the picture, it is on the right side. What is missing is the electrode. That is a specific one, with separate sense and spark electrodes, with sharp terminal that slide in to the wire.

The ragged appearance is due to the remains of the electrode gasket.

ddubble post

That thing doesn't look safe. Looks like somebody has removed the front plate and tried to put it back on with sealant behind it and only half bolted it back on. That's not a stock hole, it's all ragged. I'd buy a new furnace.

Be very careful with that. It is possible the part was removed to render the furnace unusable- perhaps on purpose?

Maybe carbon monoxide, maybe overheating, maybe...who knows?

Can you find out the history and why it was removed? If it was just defective and the PO decided not to spend the money, no biggie.

A word to the wise ;)

sorry yes its a suburban but the model is worn down, but im guessing its a nt-24. It looks like a chore to take this thing out, cause its under a bench and idont see any easy access to pull it with out taking the bench apart. I might order a high temp switch and see if it fixes it. Forgive my ignorance but is it normal to have to tear the benches aprt to get these out?? I dont see any access from the outside either.

You are missing the electrode. That said, that is an old Suburban NT series (maybe NT 30 or 32), but due to the age, it really needs to be pulled and inspected. The cast iron burner no doubt needs cleaning.

Interesting that you get 'spark' firing at all.

High Temp Limit Switch bolts onto heat exchanger.....and has to be CLOSED for DC Voltage to go to circuit board before Ignition can occur