Tripped 20 amp AC breaker won't reset

[michaeljgalvin]

2023 Forest River Forester 2401B

Was running air conditioner on generator power when I accidentally shut off generator before shutting off AC. AC shut off near immediately. AC circuit breaker tripped. Moved AC circuit breaker to full off position and tried to reset - will not reset (stays in that mid position between off/down and on/up). Waited 30+ minutes and tried again - AC circuit breaker will not reset. Everything else in RV seems fine but that breaker will not reset. Turned generator back on and tried again to reset AC breaker. Nope. Any idea what's wrong/what to do?

[Twinboat]

If pushing the lever to off " hard " doesn't get it to reset, you may need to replace it.

[Larry-NC]

Originally Posted by Twinboat

If pushing the lever to off " hard " doesn't get it to reset, you may need to replace it.

This is easy to do. The breakers are usually Square D residential breakers available for less then $10 at Lowe's or Home Depot (or Menards if you are in the upper Midwest).

Unplug from shore power and generator. Disconnect the wire from the failed breaker. Pull the breaker out from the panel by pulling it at the terminal screw area. (If you can't get it, hook a piece of wire under the terminal screw and tug on it.)

Take the breaker to the store and match it. Insert the new breaker and snap it into place. Put the wire onto the terminal screw and tighten it TIGHT. Apply shore power or generator.

[Mike134]

post 2&3 are your answer to your troubles.

[Odyknuck]

Before replacing breaker make sure AC is turned off at the unit, then you will know for sure its the breaker.

[michaeljgalvin]

Thank you - all replies above appreciated.

[michaeljgalvin]

Good news! After fully shutting off power via the rotary switch in entry to coach last night upon arrival home; turning it back on this morning and then trying again to reset circuit breaker; the breaker and now the AC worked.

[Larry-NC]

Originally Posted by michaeljgalvin

Good news! After fully shutting off power via the rotary switch in entry to coach last night upon arrival home; turning it back on this morning and then trying again to reset circuit breaker; the breaker and now the AC worked.

That switch affects the 12 volt system of the RV. The only part of the air conditioner system that uses 12 volts is the thermostat, which you apparently reset by cycling the switch.

If it happens again, you should suspect a thermostat issue.

[5picker]

Originally Posted by Larry-NC

That switch affects the 12 volt system of the RV. The only part of the air conditioner system that uses 12 volts is the thermostat, which you apparently reset by cycling the switch.

If it happens again, you should suspect a thermostat issue.

I agree with your concept Larry but the OP said the 120v circuit breaker would not reset but did so after cycling the battery cut-off (rotary) switch.
I'm still baffled??

Good news! After fully shutting off power via the rotary switch in entry to coach last night upon arrival home; turning it back on this morning and then trying again to reset circuit breaker; the breaker and now the AC worked.

[Larry-NC]

Originally Posted by 5picker

I agree with your concept Larry but the OP said the 120v circuit breaker would not reset but did so after cycling the battery cut-off (rotary) switch.
I'm still baffled??

Just suppose that the thermostat (and associated relays it controls that allow the A/C to be controlled from 12 Vdc) are in such a state that it's putting an overload or short on the 120 Vac circuit. "Breaker not resetting" is really "Breaker instantly tripping again" before you can get your hand free.

[Twinboat]

The breaker must have been to hot to reset.

[karykatz]

My electrical department suggests replacing the 20 amp breaker.

[phalexander]

The breaker probably for too hot. Id replace it because it’s easy and cheap but I’d also stay alert as it may have overheated because something is trying to draw an abnormal currant or more likely there is a loose connection.

[clr]

The primary purpose of a circuit breaker is to protect the electrical wiring in the unit. It sounds to me like the AC is still thinking that it should be running thus the AC breaker tripping when you try to reset the breaker. When you placed the DC in the cutoff position, it then reset the thermostat, thus it was no longer calling for the AC to run. Since the AC was not being called on to run the breaker was able to be reset. The AC requires AD and DC to properly operate.

[phalexander]

Originally Posted by clr

The primary purpose of a circuit breaker is to protect the electrical wiring in the unit. It sounds to me like the AC is still thinking that it should be running thus the AC breaker tripping when you try to reset the breaker. When you placed the DC in the cutoff position, it then reset the thermostat, thus it was no longer calling for the AC to run. Since the AC was not being called on to run the breaker was able to be reset. The AC requires AD and DC to properly operate.

It should be able to handle the A/C though even if it mistakenly was on. My thought is that there is a loose connection at the breaker. Or possibly at the A/C that is causing it to overheat.

[jlynn721]

Originally Posted by michaeljgalvin

2023 Forest River Forester 2401B

Was running air conditioner on generator power when I accidentally shut off generator before shutting off AC. AC shut off near immediately. AC circuit breaker tripped. Moved AC circuit breaker to full off position and tried to reset - will not reset (stays in that mid position between off/down and on/up). Waited 30+ minutes and tried again - AC circuit breaker will not reset. Everything else in RV seems fine but that breaker will not reset. Turned generator back on and tried again to reset AC breaker. Nope. Any idea what's wrong/what to do?

Did you check circuit breaker on generator?

[D9C9]

I would keep my senses alert and if you might think you smell the smell of wires over heating you might want to check and see if the control box in the AC Unit has any wires shorting. One night I smelt that faint smell and thought it was coming from out side a couple of hours later I heard my compressor kick in our out and at the same time sparks came out of my exhaust ports. The AC Unit stopped working the breaker would not reset either. It was a very hot couple of weeks in south Florida in July while I waited for a new AC and control box. Which I worked with General Electric to get expedited to an RV dealer RV World in Port Charlotte and a mobile RV tech Rick's Mobil RV. That's just another possibility.