The Stovebolt Site Forums The Shop Area Interiors How Does my TwinAir Heater Work?

Hi All,

I have a ‘55 2nd Series with a “Deluxe TwinAir” heater. Unit has a defroster lever, a two speed fan that works; but no temperature control I can find except for door on either side of the heater box. Doors can opened or closed. Heater hose from engine to heater unit and return to engine, but no inline control valve on hoses.

Anyone know how this works? Just either open or close the side doors? No intake air from anywhere. Side doors are open in attached photo.

Thanks

Yep. You regulate the temperature in the cab by opening or closing the doors and turning the fan on either Hi, or Lo.

It's a recirculating air heater rather than a fresh air heater.

That's the conclusion I came to; thanks for confirming. If it gets to hot, I'm thinking I could install a valve in the heater hoses similar to what the '70's Chevy trucks had. Is the TwinAir an aftermarket unit?

Yes, it's an aftermarket heater. It may have been installed by the dealer or even purchased from Western Auto and installed by the owner.

I have a recirculating heater. It has a shutoff valve on one of the heater hoses near the water pump to keep hot water from entering the heater core in the summer.

I never bother turning it off because it doesn't really heat up the cabin with the fan off and I drive with the windows down and intake vents open anyway.

Thanks for info Otto! I'll try as it is; and if it gets too hot there are lots of shut off/by-pass valves available; manual, cable, vacuum, electric.. Add it to the list!