Coleman roof top heat pump

Vegas1 wrote:
Thank you all for your educational responses. I currently have an outdoor 20 amp receptacle. Using a heavy duty extension cord, I plug into the coach using a 15-30 dog bone and then a 30-50 dog bone. This provides power to the coach as well as keep the batteries charged. As in my original post, I was wondering if this was enough power to safely run the heat pump. Based on your responses, I will run the generator if I need to use the heat pump.:h

OK, the WEAKEST point of your connection is the 20 amp receptacle on your house. Now, unless it is configured this way (prongs) - !. one spade vertical and one Horizontal with the round ground below them, you have a 15 amp receptacle. 20 amp wall plugs are as I described above. The 15 amp is rated at no more than 15 amp. BUT, like most House plugs, that will NOT be the only receptacle on the house wiring for that circuit. There may be other appliances(receptacles) in your house using that same wire feed. The next weakest will be the internal HOUSE wiring that supplies that outside receptacle. Then the 3rd weak point is the 30 to 15 amp adapter. Notice it is a 30 to FIFTEEN adapter, NOT a 30 to 20 amp adapter. When you plug your RV to any shore power receptacle(15/20/30/50), there are always other 120 appliances that may be powered up. For instance, your Power Converter will be powered up and will pull from 1 to 5 amps depending on what it is doing. Your refer if on 120 will pull 2.5 amps minimum, so keep it off. The Roof AC/HP will pull from 12 amps to 16 amps depending on the model and how hot or Cold(HP mode) it is outside. As a General rule, in HP heat mode, it will pull higher amps than in AC (cool) mode. But no more than that 15/16 amps. So, be aware of what is going on and manage your loads. Doug

Just get a good quality plug in meter and monitor the voltage. As long as the voltage stays good- doesn't sag much when the compressor kicks on, and stays above 110, it will be fine. It will be just running the air and converter, but I do it all the time here- good quality outlets, good quality cords. Voltage stays above 115.
Because you have a generator, I would get a Kill-a-watt- you don't have to plug anything in to it- and it give voltage and frequency, plus polarity- wiring errors.

Thank you all for your educational responses. I currently have an outdoor 20 amp receptacle. Using a heavy duty extension cord, I plug into the coach using a 15-30 dog bone and then a 30-50 dog bone. This provides power to the coach as well as keep the batteries charged. As in my original post, I was wondering if this was enough power to safely run the heat pump. Based on your responses, I will run the generator if I need to use the heat pump.:h

Chris Bryant wrote:

dougrainer wrote:
The SPEC requirement on ALL RV AC units is 20 amp service and breaker. Doug

:) That's why I didn't have to look it up ;)

I guess we should have pointed out that the spec requirement is for the INTERNAL Breaker that supplies the roof top AC and the internal Romex wiring to handle that 20 amp load. NOT the outside supply breaker/service. J-D mentioned 20 amp SERVICE, which is NOT equipped to handle RV roof AC loads. Doug

dougrainer wrote:
The SPEC requirement on ALL RV AC units is 20 amp service and breaker. Doug

:) That's why I didn't have to look it up ;)

The SPEC requirement on ALL RV AC units is 20 amp service and breaker. Doug

FIRST! Vegas, you've been around here awhile but maybe just plugged into campground pedestals. Please be sure to understand that your appliances, even if you have a 50-amp coach, are 115-VAC. A 30-AMP RV outlet is still only 115-VAC, and a 50-AMP outlet is Two 115-VAC circuits.

We have the 15000 Coleman Mach that Tom describes above, and it's a power hog. The 13500 is of course less demanding, and "high efficiency" models are available to make them still less demanding. Last I looked there weren't any 15000 high eff models.

This tells me if you have a 15000 unit, don't plan on less than the 20-AMP service that Chris pointed out is the spec requirement.

But there's another important point here. Say it's a 13500 and you're asking because you want to plug it into somebody's front hall outlet. The CORD you use has to be large gauge wire. AND the Adapter you use has to be a good one. A corded one like and not a puck like
The pucks concentrate the heat the load produces and melt down in short order.

AMP is a measure of WORK. As Chris stated, the minimum required Breaker and Service(wire size) is 20 amp. You cannot measure AMPS without something running and using current. Amps times line voltage will give the wattage. Wattage divided by the voltage will give you the amps. Or, as Chris and I do, we use a inductive clamp on AMP meter to see what any 120 appliance is drawing in amps. Having the wattage spec of an appliance and then dividing by 120, will tell you the AMP size of the circuit you will be using the appliance on. Doug

The install spec is for a 20 amp circuit.

My Coleman Mach II heat pump has run OK on voltages ranging from 108 to 140 (nominal voltage for residential service in the U.S. is 120V, delivered at 60 cycles).

I don't have the manual for my Mach II heat pump handy, RV is over at storage, manuals are in it. Current Mach 15/Mach 3 Plus A/C (more recent than my 2003 model) wants 1650 watts for "standard conditions" at 115V, needs 1900 watts continuous at 103.5 V. Full load running current is specified at 15.3 amps, locked rotor (the highest you would see starting) is 63 amps.

These brief starting currents come from starting capacitor storage (so called "start kit" is standard equipment for Coleman) or as a brief voltage surge from external power lines; the needed amps get sucked out of inertial energy from the rotor in a conventional generator.

Numbers for your A/C are probably different, but in the same range. The products have not become much more efficient over the past 10-15 years, conversion to enviromentally friendly refrigerants have worked counter to improvements in compressor A/C technology (which mostly involve making the units way oversize and running at low loads)>

These A/Cs come from a company called RV Products, the Coleman name is licensed from the descendant of the original lantern company, which actually now makes nothing itself but sells a lot of licensed stuff through its outlet store in Wichita.