Extension Cord

[Dancinman1]

31 foot 1982 International---should we use the "Dog Bone" adapter to go from 30 amp plug to regular 15 amp home service so our air on low will not melt cord? Advise on how we do this otherwise so we can run air at home base! THANKS!!!

[Belegedhel]

Have a look at the thread below. There are some good ideas and bad offered up. Basically, I have the same challenge, that I want to run a single AC at home, but I keep tripping a 20 Amp breaker, and the little adapter pigtail gets pretty hot pretty quick.

http://www.airforums.com/forums/f37/...se-152655.html

Good luck!

[Jammer]

Originally Posted by Dancinman1

31 foot 1982 International---should we use the "Dog Bone" adapter to go from 30 amp plug to regular 15 amp home service so our air on low will not melt cord? Advise on how we do this otherwise so we can run air at home base! THANKS!!!

Hi Dancinman

For most trailers the air will draw around 15 amps, sometimes a little more. In general if you're going to run the air at home you need at least a 20a outlet. That said there are people who do run it on a 15 amp circuit but I don't and wouldn't recommend it.

The dogbone connectors are usually better than the small ones but not always. Whatever you use be sure it's in good condition if you're running the air or other big loads. Contact blades clean and bright. Try to keep cord lengths short. After the air has been on for a minute or two, carefully feel the cord ends and the plastic parts of the connectors with your hand and see if they're hot. Slightly warm is OK, hot isn't, if it's hot you've got a bad connector somewhere.

[TG Twinkie]

Do it right. Have the proper 30 amp RV receptacle installed. Then use the shore power cable that is in your coach.

[Zil]

Originally Posted by TG Twinkie

Do it right. Have the proper 30 amp RV receptacle installed. Then use the shore power cable that is in your coach.

The only way!

[HiJoeSilver]

Your 15A outlet is not going to run your AC.
Being on low or medium or high makes no significant difference in the AC current requirements. Those settings only change the fan speed, which is a minimal current change.
The major current draw in the AC is the compressor which is either on or off, no low, med, high for it. When it starts it uses more current than when running due to the capacitive kick to get the compressor motor started.

[Gamehawkers]

If you do not spend the money to have the 30 amp service put in you will spend more money on repairing and replacing your air conditioning unit.

[Burnside Bob]

Originally Posted by Belegedhel

Have a look at the thread below. There are some good ideas and bad offered up. Basically, I have the same challenge, that I want to run a single AC at home, but I keep tripping a 20 Amp breaker, and the little adapter pigtail gets pretty hot pretty quick.

http://www.airforums.com/forums/f37/...se-152655.html

Good luck!

A 20 amp circuit, properly wired, is more than ample to run a single RV AC. That said, there is a caveat, which is your AC is a high inrush current device. Modern residential breakers detect high inrush current, "figure" there is a short or overload, and trip.

Depending on the brand and age of your breaker panel, you may be able to purchase a high inrush current breaker for the circuit you are plugging into. You will want to go to a large electrical supply house, like Platt Electric, or to an electrical contractor who does some industrial/commercial work. This is a bit of an arcane topic, so make sure the person you are talking with understands what you need.

Devices requiring high inrush current include air compressors, air conditioners, and high intensity lighting (HID lighting). Some electrical equipment mfgrs have a whole line of breakers appropriate to these devices, BUT they may not fit your breaker panel--many mfgrs make cheaper panels for residential use and the commercial breakers don't fit.

I found this out in diagnosing why my air compressor, which worked perfectly well on 15 amp circuits in my previous two homes, would trip a 20 amp breaker in my new garage. Unfortunately Square D, the mfgr of my garage panel, does not make high inrush current breakers that fit their "residential use" panels, so I was not able to solve my problem (unless I want to change out the whole panel).

But you may be in luck.

Be aware that your local electrical code may prohibit use of high inrush current breakers in your home panel--garage or outbuilding panels should be OK.

[lewster]

Wire in a sub panel for your compressor with the appropriate breakers required for the load.

[Burnside Bob]

Originally Posted by lewster

Wire in a sub panel for your compressor with the appropriate breakers required for the load.

Lewster:


That's an excellent suggestion for my air compressor, and one I might implement. My garage is pre-wired for an electric car charger. I didn't buy the car so I could do a sub panel or an RV pedestal utilizing the pre-wire.

Do you have any suggestions for the original poster, tho? He wanted to run his units AC, but didn't provide detail on his existing electrical.

[lewster]

Originally Posted by Burnside Bob

Lewster:





That's an excellent suggestion for my air compressor, and one I might implement. My garage is pre-wired for an electric car charger. I didn't buy the car so I could do a sub panel or an RV pedestal utilizing the pre-wire.



Do you have any suggestions for the original poster, tho? He wanted to run his units AC, but didn't provide detail on his existing electrical.

15 amps will not be sufficient to run an RV roof unit, as a 13.5K A/C draws around 15-16 amps continual with a much higher transient compressor start load.

A minimum of 20 amps is required to PROPERLY AND SAFELY run a roof A/C. without the potential or ruining the compressor or over drawing the circuit wiring or over current protective devices.

[Jammer]

Originally Posted by HiJoeSilver

Your 15A outlet is not going to run your AC.
Being on low or medium or high makes no significant difference in the AC current requirements. Those settings only change the fan speed, which is a minimal current change.
The major current draw in the AC is the compressor which is either on or off, no low, med, high for it.

While it is true that compressors do not have separate low/med/high settings themselves, it is not true that the fan speed has no significant effect on the current draw.

I have an ammeter and voltmeter permanently installed on the breaker panel of my trailer. I also know some of the theory.

I have found that I can typically run both the front and rear air conditioner in my trailer on a 30 amp circuit provided that they are run on low fan speed and all other loads are off including the fridge (Converter too sometimes). Air conditioner compressor current draw depends on many variables but chief among them is the amount of thermodynamic work the compressor is doing, a product of the BTU/h being moved and the temperature difference between the inside and outside coils. Running the fan on low reduces the BTU/h being moved and also reduces the compressor current draw.

Low supply voltage also increases the amp draw of the compressor.

Originally Posted by Gamehawkers

If you do not spend the money to have the 30 amp service put in you will spend more money on repairing and replacing your air conditioning unit.

This simply isn't true.

On the facts of engineering, physics, and air conditioner design, lower voltage causes more heating in the compressor stator coils. Heat does contribute to the eventual breakdown of the insulation in the coils, leading to overheating. Compressors don't last forever; actually using the air conditioner shortens its remaining life. Using the air conditioner in hotter weather or humid weather or dusty conditions -- and indeed, on slightly lower voltage -- shortens its life somewhat more quickly than using it in less demanding conditions.

The thing is that most 30a campground outlets, on a hot day, are going to deliver lower voltage to the trailer than a 20a outlet in someone's garage, as long as the shore power cord is kept short and is of the proper gauge.

I typically measure campground 30a outlets, during a hot weekend day when the campsites are occupied, at around 105-110 volts at the pedestal. Garage outlets are typically 120v or a little more, even with a 16a load connected. Actual measurements.

I've run the air conditioning in my trailer down as low as 95 volts, on days when it was hot and we really needed it and that was all the power that we got from the pedestal at the campground.

My air conditioners are 6 years old and still going strong.