Testing AC at home

[rucos]

Originally Posted by BobnGayl

I doubt it. A 220 volt dryer plug puts out 220 volts AC to ground. A 50 Amp RV plug has 2 - 110 volt legs to ground. Totally different if you plug your 50 Amp RV plug into a 220 volt dryer or range plug you will fry your trailer electricals. The trailer breakers won’t protect anything as they trip on excess current, not excess voltage. Don’t do it!

I installed a 30 and 50 amp pedestal at home many years ago. Takes some serious wire. 4 gauge as I remember. A 30 amp outlet is much simpler, costs less and requires only 10 gauge wire for short runs. Highly recommend doing this - comes in very handy for working on the trailer.

sorry trailer is 30amp

[Wazbro]

Originally Posted by SS-Houston

Thanks to tall for the help. It looks like everything is OK on the unit, but I seem to me missing a freeze sensor, which allowed the unit to freeze up on the last trip. Does anyone know if they can be retro-fitted onto the Domenic units? I'm not sure the model, but it's whatever was standard on the Classic Ltd in 2011.

Glad it's working. Not sure about Dometic, when I bought a control unit to add a remote thermostat to my Coleman AC it came with a freeze sensor, (freeze sensor didn't come standard with AC mounted controls).

[Adiredneck]

I have two Yamaha 2000 gennys that I can connect in series to produce enough juice to run my a/c. Every Spring, as part of my pre-season prep, I hook up the generators and run each heat pump (one at a time), and thereby get to check both my a/c, and my generators under load.

[Wooden Rivet]

Originally Posted by SS-Houston

First the main question, then I'll dig in a little bit: is there a way to run the AC on a standard 110v 20A just for the purposes of testing/troubleshooting? Any setup tricks to making it work, like throwing the rest of the breakers?

On the last day of our last trip out, the AC stopped blowing cold. I shut it off briefly to let it thaw (if that was the issue, as we have run into with our home units). This seemed to help, but only briefly, then it was back to being warm.

I don't want to pay the money or deal with the hassle of getting to a shop for diagnosis (at least until I've tried my hand at it). But it's July in Texas, so I don't want to go on another trip without a functioning AC.

Is there a way to home-diagnose? Anyone have any idea on where/how to start? Thanks!

Have used 20 amp circuit several times to power our 13500 btu unit. That is about all it will do though. Unplug convertor and anything else that runs on 110volts. Should be fine. As far as diagnostics go, if it doesn't run, and you have ruled out capacitors, replacement is usually your best option. Most are hard and expensive to repair. Good luck.

[J2Becker]

Originally Posted by Wooden Rivet

Have used 20 amp circuit several times to power our 13500 btu unit. That is about all it will do though. Unplug convertor and anything else that runs on 110volts. Should be fine. As far as diagnostics go, if it doesn't run, and you have ruled out capacitors, replacement is usually your best option. Most are hard and expensive to repair. Good luck.

I would add that in addition to tripping the breaker to cut power to the converter, put the fridge on propane.

[A W Warn]

My advice: Instead of taking anybody's experience as the way it can be done, read the air conditioners owner's manual, then make your choice about risk of running the air conditioner at your location. The manufacturer is very clear about minimum circuit amperage, minimum wire size, and maximum length of wire.

The manual for my Dometic Penguin says 115 volts, 20 amp circuit, 12 ga copper up to 24' in length.

My experience:
At my home on a 20 amp circuit, that wire length measure begins at the breaker in the main service panel, includes all wiring through the house to the receptacle, then includes the length of the power cord, and then includes the wiring within the trailer.

Voltage at my home is ~121 volts at the distribution panel. I've measured it several times. So even with additional wire length and voltage drop because of excess wire length, voltage inside my trailer exceeds the required 115 volts for the air conditioner.

I've done this; ~50' of 12ga wire on a 20 amp circuit, 25' 10 ga power cord, and ~15' 12 ga wireinside the trailer. There is also some loss at the plugs, adapters, and wire connections. I have run the air conditioner in my 25' Safari for days at a time at home on a 20 amp residential plug.
Did I damage the air conditioner? Maybe. I don't know how to measure damage.
However, it is still running, at 20+ years old.

[Mollysdad]

Originally Posted by rucos

What i did is I have a homemade extension cord that plugs into my dryer outlet , I made it years ago for a contractor working at my property who needed a 220 plug for his compressor.
I just bought some proper gauge wire and put a plug and receptical on it, unplugged dryer and plugged in the extension and then my trailer cord and it worked great. Good Luck.

Um, we're missing some critical information here.
What rucos is saying is he made a 240v to 240 v extension cord.
First, a dryer plug may look like a 30 amp RV plug but it's different. The neutral is angled rather than round. So the RV power cord will not plug into a dryer circuit.
That's a good thing because the dryer plug is 240v.
A clever "shade tree" electrician can make a dog bone that works, but let's be clear, YOU MAY NOT PLUG A RV CORD INTO A DRYER OUTLET.
We've heard the horror stories of a 'real' electrician wiring an RV plug like he does all day with dryer outlets and things go boom!

[A W Warn]

Originally Posted by SS-Houston

Thanks to tall for the help. It looks like everything is OK on the unit, but I seem to me missing a freeze sensor, which allowed the unit to freeze up on the last trip. Does anyone know if they can be retro-fitted onto the Domenic units? I'm not sure the model, but it's whatever was standard on the Classic Ltd in 2011.
<<snip>>

I'm not sure about the Penguin, how it was done originally.
I installed one on a Dometic Brisk Air. It inserted into fins of the coils on the cold side, then plugged into the control module.

[cwf]

We are in dangerous waters here...

No insults, this is scary stuff

[rucos]

Just a note that I also have a Progressive Industries electrical management system installed in the trailer..... it monitors 10 different functions on power coming in...bad ground, high or low voltage etc and will shut down the supply if things aren't good...... all was checked and good before turning on AC. Stay safe.

[rucos]

Originally Posted by smithcreek

He's probably just using one 30A leg of the dryer outlet.

Sorry yes I should have mentioned that but forgot. My apology I went out this am and re-checked cord. thanks for catching my error.

[suncoasteng]

Originally Posted by bibbs

Ok who called the electrician? I’m here now. First if you are running one air conditioning unit and nothing else, (no fridge,water heater no battery charger) 20 amp is plenty of power, as with all Appliances the shorter the cord the better. 12 gauge minimum, most laundry and kitchen circuits are 20amp.

Good answer! If a 30A outlet runs your RV, it is capable of running the hot water heater, AC, microwave and battery charger/inverter simultaneously.

If you decide to plug into a 20A standard duplex outlet at home, a friends house, a campground or park you wont have a problem - Provided that you turn off the hot water heater, do not use the microwave and turn off all 12V loads like radio, fans, etc. Wait a few minutes for battery charger to stabilize charge on your battery, then turn on AC fan only. Wait one minute, then turn down temp on AC and set to cool. Just make sure you have a good quality cheater plug (20a to 30a) and do not have an extension cord more than 25 feet long

[SS-Houston]

I ended up installing an Easy Start system yesterday - which was pretty simple. I looked at a lot of videos online to make sure I didn't do anything too foolish, and this one was the most useful for Airstream owners:

https://www.youtube.com/watch?v=O4o0g4dTYYA&t=1s

So many others were on units that are set up very differently, and translating over wasn't as easy for me as it might be vor others.

I was able to run before the upgrade - so I'm not sure exactly how I'll be able to tell that it's an improvement - but I will definitely feel better using it as a home addition when it's in the driveway.

Thanks to all for your help!

[Wazbro]

Originally Posted by suncoasteng

Good answer! If a 30A outlet runs your RV, it is capable of running the hot water heater, AC, microwave and battery charger/inverter simultaneously.

No it can't.
AC 11-17 amp model dependent.
Microwave 11-14 amp model dependent.
Water heater 11.7 amp on electric.
Battery converter 1-6 amps model and battery charge dependent.
That is 34.7-48.7 amps a bit much for 30 amps service.

[Silvr_Bullet]

Just like sizing a generator for home use, it’s not likely you will be running all the appliances at one time.