Wire gauge to small to run AC properly?

[timothy l]

My Casita is a 1997. I replaced the AC last year and the unit cycles on and off frequently, like 45 seconds on and two minutes off. I have noticed the wiring running to the outlet under the AC is very small. I am not sure what gauge it is but it appears to be smaller than 14 gauge. I suspected this is why it cycled so often so today I ran a heavy extention cord to the AC and now it cycles normal.

I tried searching threads relating to this but can't seem to find any. Has anyone else had this issue, and if so how did you route the heavier wire to the recepticle?

Mine has the window style unit on the floor at the front of the trailer. Even the old unit seemed to short cycle before it died.

Thanks

[AC0GV]

Originally Posted by timothy l

My Casita is a 1997. I replaced the AC last year and the unit cycles on and off frequently, like 45 seconds on and two minutes off. I have noticed the wiring running to the outlet under the AC is very small. I am not sure what gauge it is but it appears to be smaller than 14 gauge. Thanks

Number 14 should take 15 amps and # 12awg 20 amps. I'd run the 12 and be done with it, to be sure we would need to see the specs from the A/C.

[Markz]

I used 12 awg just because I aired on the side of caution.

[timothy l]

I believe the unit is 8000 BTU, and I will replace it with 12 ga.,

I guess the real question is has anyone actually done this in a Casita Spirit Deluxe, and if so how did you route the wire? Can you tape the new wire to the old wire and pull it through? It appears the wire runs along the floor, behind the dinette and under the bathroom which is where it would get tricky. Thanks for the replies.

[starbrightsteve]

This is a great question to ask on the Casita forum.

[Martin B.]

Somewhere on your air conditioner, there is a label that tells you the electricity requirement. Base your wire size on that. Be sure to add other electric draws to that number, if they will be used with the A/C. That will determine your wire size. 15 amps for 14 gauge; 20 amps for 12 gauge; 30 amps for 10 gauge.

[Mark Bradley]

According to the Canadian Electrical Code there is a 80% derating factor that applies to the current draw on a particular size of wire and it's associated breaker. So with a 15 amp breaker maximum current draw on #14 wire is 12 amp. With a 20 amp breaker the maximum current draw on #12 wire is 16 amperes. And with a 30 amp breaker the maximum current draw on #10 wire is 24 amp. I would suspect The National Electrical Code stateside is the same. If there is a very long distance to run a cord then voltage drop comes into play and a larger size of wire would be needed. My suggestion would be to look on the nameplate of your A/C and see how much current it draws and with that number size the wire and breaker accordingly.

[Jann Todd]

Originally Posted by timothy l

I believe the unit is 8000 BTU, and I will replace it with 12 ga.,

I guess the real question is has anyone actually done this in a Casita Spirit Deluxe, and if so how did you route the wire? Can you tape the new wire to the old wire and pull it through? It appears the wire runs along the floor, behind the dinette and under the bathroom which is where it would get tricky. Thanks for the replies.

Strip a couple of inches of wire and twist the wires together as tight as you can then tape them. Just taping can be a disaster if it gets a little hung up. Been there done that.

[gordon2]

Originally Posted by timothy l

I believe the unit is 8000 BTU, and I will replace it with 12 ga.,

I guess the real question is has anyone actually done this in a Casita Spirit Deluxe, and if so how did you route the wire? Can you tape the new wire to the old wire and pull it through? It appears the wire runs along the floor, behind the dinette and under the bathroom which is where it would get tricky. Thanks for the replies.

IDK how the Casita is built but I would bet big money that the current cable is secured and wont pull out unless you remove all attachments. It might be easier to leave the current cable in place (disconnected) and run new wire using a fish tape...

https://www.youtube.com/watch?v=lm5zUCca7jM

[Eddie B.]

Originally Posted by timothy l

My Casita is a 1997. I replaced the AC last year and the unit cycles on and off frequently, like 45 seconds on and two minutes off. I have noticed the wiring running to the outlet under the AC is very small. I am not sure what gauge it is but it appears to be smaller than 14 gauge. I suspected this is why it cycled so often so today I ran a heavy extention cord to the AC and now it cycles normal.

I tried searching threads relating to this but can't seem to find any. Has anyone else had this issue, and if so how did you route the heavier wire to the recepticle?

Mine has the window style unit on the floor at the front of the trailer. Even the old unit seemed to short cycle before it died.

Thanks

The ac should be on it’s own circuit,now the manufactures use the cheapest AC receptacles they can buy $1 each.Plus sometimes the wires are loose on them,very bad.I replaced all my ac receptacles with the old commercial types-20 amp.Solves a lot of problems.

[Eddie B.]

Originally Posted by Eddie B.

The ac should be on it’s own circuit,now the manufactures use the cheapest AC receptacles they can buy $1 each.Plus sometimes the wires are loose on them,very bad.I replaced all my ac receptacles with the old commercial types-20 amp.Solves a lot of problems.

Check to see if the plug is getting hot,that will tell you something right there.

[computerspook]

Originally Posted by AC0GV

Number 14 should take 15 amps and # 12awg 20 amps. I'd run the 12 and be done with it, to be sure we would need to see the specs from the A/C.

You nailed it

[Friz]

Before doing anything that's a lot of work, let's just see what the problem is.

1. Get a voltmeter. $5 at Harbor Freight.
2. Measure voltage at trailer plug with AC on. Should read at least 110v. Shouldn't drop > 5v w/ compressor on. 105v is marginal.
2. Measure voltage at the socket AC is plugged into. Should be within 2v. of #2
If it drops 5v or more, wiring or circuit breaker within the trailer could be the problem.
If it never goes below 110 volts it's not the wiring. If above tests fail, then go to work.
3. The "short cycling" by the Casita AC near the door is usually caused by the cool air not getting out of the area. Make an air deflector from plastic or heavy cardboard to deflect the air out towards the kitchen area. Cereal boxes, political signs etc. are good raw materials. Even a small Honeywell table fan from Walmart will help a lot. They focus the air stream well, can feel the breeze in bed.
I would hate to do all that work and find out it was a bad connection somewhere.

4. If the supply voltage is too low, the compressor will draw more current to make up for it, overheat and cut out. It wasn't the thermostat that cycled the compressor off. To check for this condition when the AC cycles off, pull the plug. Rotate the temperature control to cooler position. If you hear a click, something else shut off the compressor, like overheat.

[computerspook]

Originally Posted by Friz

Before doing anything that's a lot of work, let's just see what the problem is.

1. Get a voltmeter. $5 at Harbor Freight.
2. Measure voltage at trailer plug with AC on. Should read at least 110v. Shouldn't drop > 5v w/ compressor on. 105v is marginal.
2. Measure voltage at the socket AC is plugged into. Should be within 2v. of #2
If it drops 5v or more, wiring or circuit breaker within the trailer could be the problem.
If it never goes below 110 volts it's not the wiring. If above tests fail, then go to work.
3. The "short cycling" by the Casita AC near the door is usually caused by the cool air not getting out of the area. Make an air deflector from plastic or heavy cardboard to deflect the air out towards the kitchen area. Cereal boxes, political signs etc. are good raw materials. Even a small Honeywell table fan from Walmart will help a lot. They focus the air stream well, can feel the breeze in bed.
I would hate to do all that work and find out it was a bad connection somewhere.

4. If the supply voltage is too low, the compressor will draw more current to make up for it, overheat and cut out. It wasn't the thermostat that cycled the compressor off. To check for this condition when the AC cycles off, pull the plug. Rotate the temperature control to cooler position. If you hear a click, something else shut off the compressor, like overheat.

All great. But still sounds like to small of wiring and that could be a disaster later. Heck I think your steps might be a good first step as you don't want to actually have to many variables in play. Probably need to find the problem, but then verify the wire size and if it is under spec then replace it regardless of what is found

One other step I would take is to run an extension cord from a known good outlet and then plug the air conditioner in there and see if it works or cycles.

One other possibility. Most of these units have a temp sensor that is in the air stream before the cooling coils. That is what turns it off and on. But some times these are not well mounted and if they get loose and are touching the cooling coils you will see this.