Air Conditioner Tripping

You need to monitor the current to see if after start up it exceeds the 23amps. If it does the compressor could be deffective, other wise replace the breaker.

If you replace the breaker, Chief, make sure it is the same size one. It is there to protect the wiring against the overcurrent that might arise from a faulty air conditioner.

Sounds like you have a fault in the A\C unit. If it was wiring issue such as a short, the breaker in most cases would trip instantly.

At this stage, unless you know the units workings, I would be calling a A\C service provider.

It's probably the Compressor, but it could be an issue in the controls as well.

Regards,
Sapper.

When the A/C starts up, the fan starts first, then the compressor. Is this the "after some time" you refer to. Compressors use a higher current when starting-up than when running.

Good point!!!

Forgot about that little detail... Its is sounding more like have a compressor problem..

Regards,
Sapper

Could be a bad start/run capacitor....test it with your capacitor tester....or it could be your heat coming on at the same time, if you have a heater....

Typical wiring schematic for window unit...

http://www.american-appliance.com/old_Site/service_pages/window_ac/

There are many possible causes, but for these symptoms I would check the condenser for cleanliness, the condenser fan for operation, and the system for possible overcharge of refrigerant.

Could be too much voltage drop in wiring.

1. Has this air conditioner ever worked on this outlet/breaker? If yes, what changed just before this problem started happening?

2. You checked the cable and wiring - what size/gauge wire is it and how long is the wire from the breaker to the receptacle?

3. How much time elapses from when you push the 'ON' button until the breaker trips?

4. When you push the 'ON' button, does the compressor actually start and cool air comes out, or does the compressor just 'hum'?

5. Is this a new unit or used? If used, how old?

6. Do you have another receptacle/circuit that you could try the air conditioner on before you call a repairman?

<...Could be too much voltage drop in wiring....>

In that case the wiring hasn't been installed correctly and the circuit should be de-energised until a local qualified electrician has checked it out.

Is it new or how long it was running w/o tripping?. The mcb may be defective or use C type MCB. Also tell us when was it last serviced,normally agents should do it.

There are some pieces of information missing to pinpoint the problem.You didn't mention if a) The 23A reading was at start up and then levels to full load (9.6A). b) What wire gauge is used in that circuit. c) If is a dedicated circuit. Is this the unit you always had or is a new one with higher tonnage than what you had before?. Let me go orderly.First read the specs label it should show the FLA on the cold mode and also on the heat mode (if it's an AC/Heat pump).

a) If the 23A is a constant reading that's just a little less than 2.5 the normal load so you've got either bad compressor, overcharged refrigerant lines, low level refrigerant ( in the compressor it acts as a lubricant too), or bad bearings, adding mechanical drag and therefore increasing the load demand; that means you've got bad motor, bad compressor or both. If the unit is an AC/Heat pump and the sum load of both modes comes about 23A it means it's pulling both modes simultaneously. That would not happen with an electromechanical control because the 2-pole (?) relay would connect either load not both by swinging over. If it's an electronic control it could happen if it's faulty and is sending signal to both modes. Result will trip the breaker because it's overloading it. You've got a bad control module.

b) If it's an old house, it was mostly used #14 gauge wire which max load is 15A, is going to trip the breaker after a while for 2 reasons: It's overloading the breaker (23/20) and it's overloading the wire ampacity (23/15) so the problem gets compounded. The breaker is doing its job!.

c) If it's not a dedicated circuit, something else might kick in while the unit is running, overloading the circuit and tripping the breaker. Again, the breaker is doing its job!. To summarize. Make sure you've got the right wire gauge in the circuit. Make sure it's dedicated. Last but not least, if it's a new unit with higher tonnage you've got 2 options bring her down to the original specs or replace the wiring in the circuit to bring it up to specs. A 20A breaker should never trip on a 9.6A load.

Check operation of condenser fan motor, compressor winding, condition of coils, capacitors and control wire diagrams with the as stance of trained a.c mechanic.

Make sure the breaker is HACR rated.These breakers are designed to take the high-start current of the compressor.

If the breaker is also used for turning the unit off and on, the breaker should also be rated for Switch-Duty.

Based on the information you provided, the the 23 amps seems to be the starting current,which will be solved by using the right type breaker.

If this is the running current,you have other problems, such as a fan motor with bad bearings(They are not always noisy,they are usually sleeve type bearings that wear out and let the rotor drag the stator) replacement end-bells are usually available. (A very simple repair:4 screws+nuts after removing fan from unit).

High head pressure on the compressor can also increase current draw.

Make sure the evaporator and condenser coils are clean.They can be cleaned easily at a manual car wash, but be careful not to bend the fins with the high pressure, and do not direct the water into the control box.Everything else outside of the window is safe to wash down.The inside(evaporator coil) is safe to wash down if you observe the previous caveat.

After cleaning, let the unit rest at a slight angle toward the back to drain.When it has drained properly, reinstall in window.

Install a new air filter of the proper type.

A coil cleaning chemical is also available the foams and pushes dirt out of the coils, but it is not a good as the car-wash wand.If you buy the coil cleaner, be sure to get the "No Rinse" type that is safe to leave on the coils without the need to rinse it off.

Good luck!

Is that 23A continuous or only when starting?

If it is only on starting then that's about right.

If it is continuous then you are either over gassed or the supply voltage (at the compressor) is low.

If the supply voltage is low then you either have loose connections or undersized conductors.

Does the aircon actually seem to work ok apart from this nuisance tripping?

No one asked yet-

Has this A/C unit been in place for some time and operated OK, but now is a problem or is this a NEW installation?

IF it is new, your breaker may need to be changed to one that is designed to tolerate the inrush current of the compressor start-up. Some residential units do not have this capacity and will see that inrush as a short and trip "too soon".

If it has been operating OK for a while and is just now causing a problem, you are back to the service call.

It could be a few things but it depends on when it trips the breaker. On most single phase A/C units the compressor has a start winding with a start capacitor. When the compressor is called for the start relay will energize the capacitor and give the compressor a "kick start" in the start winding of the compressor motor. After the compressor comes up to speed it develops back EMF (electro motor force) that de-energizes or opens the relay and moves the power directly to the run winding keeping the motor running. If the compressor bearings are getting tight or if the start capacitor is weak the compressor will draw high amps trying to start.

If it trips while running, again the compressor may have tight bearings in it (replace compressor) or the unit may simply be dirty causing high discharge pressures causing the compressor to run over amps. Wash out the unit thoroughly and try again.

If it is a window style unit it would be cost effective to simply replace the entire unit instead of the compressor since you would get a new warranty with a new unit and odds are that after you change the compressor out the fan motor will fail next.

Many good points have been presented hear, like the wire size, and length, are the connections tight. If the problem is new, and the A/C has functioned properly in the past we need to determine what has changed, creating the malfunction. If you find the compressor windings shorted or grounded (or other major repair required), consider the age of the unit; can you relied on a warranty. A window shaker is like a Bick Lighter, not designed to be worked on, but replaced. If you get more than six years of service, your doing real good.

It could be the compressor or possibly the condenser coil is plugged on the air side with debris from nearby cottenwood trees. You can check that visually and clean the condenser coil if needed.

If it isn't that obvious, call a reputable serv ice company to check it out for you.

Lou Bindner

Its cousin Lou