Obsolete direct vent gas-fired wall heater

[Stumpy]

It's been cold and I fired up an old Sears heater. Works great but it won't really turn down very low. The thermostat doesn't really change the output. Don't have a manual, must turn off the gas valve to turn off the burner.

That's the parts diagram and you can see it is just a basic heater that Sears doesn't stock many parts for any more.

Is it worth banging on the valve or wiggling the thermocouple? If I needed the $185 substitute gas valve, I'd probably be better off buying a whole new heater.

[David L. Martel]

Stumpy,

The gas valve has a long copper cylinder called the bulb which senses the air temp. It's probably dead and is not replaceable. You need a new valve or a new heater.

Dave M.

[Stumpy]

Well, it probably was installed in the '60s. Should be retired.

Northern Tool sells a similar one for $400 new. Makes more sense than spending almost $200 to repair the decrepit one.

[Stumpy]

I just looked up "modulating, bulb-type thermostat" and realized that it would adjust the size of the flame rather than turn it on or off. Maybe the adjustment range is too small, and I could adjust the spoiler screw on the burner to reduce the size of the flame. It's rated at 14,000 BTU/hr normal output and bakes us unless it is

[willshak]

Did you read the Recall Notice by those diagrams?

[Stumpy]

Yes I did, but it looked like it was specifically for LP gas setup. I'm natural gas here. It didn't say what date the recall was.