A/C fan runs then stops

[cruzaire]

95 Land Yacht 30 ft, front roof mount A/C fan runs for about 10 seconds then stops. Compressor never comes on. Checked the black capacitor with ohm meter, appears ok. Checked the dual capacitor with ohm meter appears ok.
Removed leads on all and discharged before checking. Measured PTCR as 47 ohms (approx).
Any clues to where to look next?
Unit is Penguin DuoTherm with thermostat in the ceiling vent cover.
Thanks.
Tim

[92landyacht]

Does the low voltage light come on?

[wvabeer]

Make sure the capacitors and voltage are good.

[HowieE]

The compressor would not come on in that short of time so lets look at the fan. How long before the fan will come on again?
If you have an amp meter measure the running current of the fan. If it is high and there is a clickson on the fan motor. It may be going out against the clickson.

I am assuming it is not blowing the breaker.

[wvabeer]

Make sure the capacitors and voltage are good.