In article ,
Mike Spencer wrote:

PROBLEM: Starting torque is okay with either motor in warm weather.

For either motor, at winter temps (say, 20F to 0F or lower) I
have to turn a propane salamander on the compressor for maybe
15 minutes in order to start it. Once started, and with
medium air use, its own heat keeps it warm enough to restart
in the cold.

Does it have unloaders? If not, perhaps electrically unloading it would
help to start it. Then again, gearing it down might also help -
particularly if it already has unloaders.

Sketch of an electric unloader:

Compressor out======+======checkvalve====tank===piping to shop====
| |
| |
Electrically operated valve to air

Set up where the valve is operated by a time delay relay such that the
valve is opened for the first 10-15 seconds each time the motor starts.

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