AC and heater clicking

[ldmoss1]

I have a Forest River Salem with 30 amp electrical system and a single AC unit. Occasionally I hear a clicking when the AC is trying to come on. I hear the same clicking when the heater is trying to come on. I take it to be maybe contact points or something similar. The clicks come from the area of the AC. Anybody have any idea what it might be and how I could get to it to see. Thanks.

[Bama Rambler]

Sounds like a relay in the control box. You should be able to remove the filter grill and see the box.

Is the A/C or furnace failing to start when you hear it?

[ldmoss1]

Yes, it won't come on as long as it is clicking. When the clicking stops it will come on. I'll check the control box tomorrow.
Thanks,
Larry

[Flybob]

The clicking in the furnace is the piezo spark generator that lights the furnace. The click in the AC is the compressor relay. There is a control board that activates the AC compressor. The control board contains a timer circuit that prevents the compressor from starting for a period of time since it last shut off. This allows the head ( pressure ) to equalize so as to not lock up the motor on restart. If the Thermostat calls for cooling ( relay click) and the timer has not timed out it the relay will click back out. This could happen several times if the AC compressor tries to start immediately after shutting off.