a/c electrical question

[Tractorat]

It seems like, when I used to turn on the a/c in my TT when it was plugged into the socket on the outside of my garage, it would always trip the breaker (15 amp) as soon as the compressor kicked in. So, if I wanted to run it from home, I would have to plug into a 20amp ckt. But, when it was so hot this last couple of weeks, just for grins, I turned on the a/c and it worked fine.



I probably need to take a good look at my breaker panel. But, does anyone know if maybe, because of aging, the a/c might have a lower electrical draw than it used to ? Its a Carrier.



Thanks,

Mike

 

[tkerrigan]

Most likely, the reefer was on when it tripped on the 15a? 15a will run most of these ac's, if they are the only thing turned on.

 

[Silver Ratler]

Circuit Issue

It really depends on what else you have on that circuit... ... my son is an electrician and he installed a dedicated outlet for our 5er... ... we went 50 amp due to dual AC units. His recommendation was to go with a 30 amp circuit to avoid problems with only one AC... . problem is initial draw on start up of compressor.

 

[jelag]

I assume that your talking about the circuit breaker in the house, not in the trailer... I can only assume there is something else on the same circuit that was running when the breaker tripped and not on when the breaker didn't trip...

Or the inverter in the trailer had a large draw at the time you tired to start the AC...

If in fact you have a 15 amp circuit I would assume this is 14 gauge wiring in your house. What would really worry me... . is a low voltage condition when the AC ran... this low voltage condition will greatly shorten the life of the AC... .

I suggest watching the voltage with a digital volt meter at the time of AC start and run... anything more that about 5% off means a problem...

On my 5er I ran an 8 gauge, 30 amp circuit from the panel to the outside of the house... I know, 8 gauge is rated at 40 amps not 30 but its over 65 ft from the panel to the outlet and I didn't want any voltage drop... .

Hope this helps...

 

[AClayton]

It seems like, when I used to turn on the a/c in my TT when it was plugged into the socket on the outside of my garage, it would always trip the breaker (15 amp) as soon as the compressor kicked in. So, if I wanted to run it from home, I would have to plug into a 20amp ckt. But, when it was so hot this last couple of weeks, just for grins, I turned on the a/c and it worked fine.



I probably need to take a good look at my breaker panel. But, does anyone know if maybe, because of aging, the a/c might have a lower electrical draw than it used to ? Its a Carrier.



Thanks,

Mike

Too many variables to answer to... . A 15A breaker will run 1 A/C but the starting amps is marginal. The starting amps is usually 80 to 100% of running amps on a very hot day..... couple that with other things on the circuit and you can get into trouble. If your plugged in and the fridge is running on electric,that's 4 amps right there subtracted from your overall 15... ... the convertor will draw an amp or 2 depending on your 12V load at the time. That is why a 20A minimum is required for operating an RV. A circuit breaker will have a tendency to heat up substantially when at or near thermal load rating.



Anyway,to answer your question... . No,aging has nothing to do with lower amp draw..... if anything,it will draw more as it ages. But only in very small percentages and you can make up for that with 'hard start' accessory kits sold by your unit manufacturer..... may have one already if it's a Carrier!!



Alan

 

[Wooter]

If you let the fan run continously, and let the compressor cycle on and off, it may not pop the breaker when your on the 15 amp; if you have to use that circut? We had a "DOMETIC" 13500 and from a dead start, it gave my 4000w gen a hard time without letting the fan run all of the time. I switched to a 15000 Dometic and that one starts eaiser ((doesn't pull as many amps to start)



for what its worth.

 

[AClayton]

X2 on Wooter's post!!

 

[Tractorat]

Thanks,

Yeh, I can run the fan all day on that ckt. It was just when the compressor kicked in that it popped the breaker. I have a 20 ckt that I usually run it on,



Just for grins, I may hook it up to my little 1800 watt gen to see if it will work. Its seems like it used to pop the breaker on that also.

 

[Bob Cochran]

Yes they will run on a 20 amp circuit and I have run mine on a 15 before but nothing else was running on that circuit. Most motors will take about 150% of nameplate run amps to start called lock rotor current. I am guessing the compressor in our units are the same. To lower this large start current they use capacitors to lower the start currents. Depending on the design of the motor and start circuits will allow it being used on 15 or 20 amp circuits. Oh and age will make the start currents typically higher but not noticeably.