AC reset question

[wchandler]

What generally is the problem when the AC does not restart when you simulate an overflow by removing the switch and of course then replacing it? Thanks for any info.

[David A. Andersen]

what are you talking about?

Are you testing the overflow pan switch?

Many units will not come right back on when you interrupt control circuit power. They timeout to allow equalization of refrigerant pressures.

If it never came back on, you did something wrong when you "reinstalled the switch"…

Why are you dismantling anything?

[John Ritter]

if it is a mechanical float switch and you inverted it,it may be stuck

[Bruce A. King]

Originally Posted by wchandler

What generally is the problem when the AC does not restart when you simulate an overflow by removing the switch and of course then replacing it? Thanks for any info.

Did the t-stat display power back up?
Or, if it has no display, can you hear the relays in the t-stat click when you change modes?

When you interrupt the control voltage and reenergize it, it causes a slight surge that can blow a weak fuse in the air handler. Yes, fuses get weak, its called metal fatigue. Some blown fuses are simply "bad fuses" with absolutely no cause other than age. Air handler fuses are typically 3 to 5 amps and often use one of the common types of automotive fuses.

[wchandler]

Thanks, Bruce. That's what it was. the t-stat did not display, replaced the fuse and it powered up. Adding fuses to my inventory now.

FYI David Anderson: I check the pan overflow switch as a part of my inspection - don't you? It's a simple and important thing to do and when the unit shuts down, it's easier to remove the AHU door panel to check the A coil - you check the A coil don't you?

[David A. Andersen]

and of course then replacing it?

So what's with this comment?

What do you have to 'replace'?

I know your used to have compliance with the Florida only group, but you don't have to show what a flaming *** you can be...