Adding 2nd A/C

[TexasRV]

Hey guys! have a 2017 Class A Evo. 30 amp one a/c. We live in Texas and have been on the road for 3 months. Since we only have the one a/c - on really hot days like today (100deg) coach wont get much under 85 deg. I tried blocking the windows, cabinets etc. One tech I talked too suggested putting in a second a/c. They split the amps and double the air. Anyone try this? Does that really work? someone else said the did on their fifth wheel for around 3k. Any suggestions/experience with trying it.....

[txc2936@yahoo.com]

That could be tough on a 30 AMP circuit. The starting amperage will blow the CB.
If you do this. I would wait till the first unit is started and running prior to starting 2nd unit. Make sure your water heater is off, and Refrig. while running 2 AC units.

I think a replacement RV with 50 amp service and twin AC units might be the best bet here...

[Beau388]

Originally Posted by TexasRV

Hey guys! have a 2017 Class A Evo. 30 amp one a/c. We live in Texas and have been on the road for 3 months. Since we only have the one a/c - on really hot days like today (100deg) coach wont get much under 85 deg. I tried blocking the windows, cabinets etc. One tech I talked too suggested putting in a second a/c. They split the amps and double the air. Anyone try this? Does that really work? someone else said the did on their fifth wheel for around 3k. Any suggestions/experience with trying it.....

Several owners have add a 20 amp cable from the pedestal to the A/C just for the second A/C. My coach came with 30 amp service and I found I could not run the single Mach 15 A/C with the microwave, so I converter the coach to 50 amps and added a Mach 8 heat pump in the bedroom.

Another alternative is to use two Mach 3 PS. There is even an new model Mach 3 PS with soft start and quiet fan. They only draw about 13 amps where the Mach 15 draws 15/16 amps.

Finally, there is a Mach 8 Polar Cub that draws only 9 amps. As with all Mach 8s, it has two motors: a quiet two speed fan for the evaporator and single speed one for the condenser. <https://www.rvpartscountry.com/> It should wire in easily as all Plant 750 coaches have the wiring chase for a bedroom fan.

I highly recommend a Mach 8 for the bedroom because it so much quieter than the Mach 15, 10 or 3 with only a single motor.

[71_340]

You can probably run a second unit if you equip both of them with an Easy Start and run nothing else (microwave, water heater, coffee pot etc.). Just stay with a 11K BTU unit for a second AC.

The other option would be a power management system but that will be pricey and pretty involved to install.

[Pete'sMH]

I added a second unit last summer. It was an interesting and fun project. My coach didn’t have an available ceiling vent so I had to cut a new hole. Hardest part was toting a 100 pound machine up to the roof. I used 12/2 Romex which I ran through the ceiling and down through the bathroom wall to the basement and over to the electrical compartment. I put a circuit breaker and an inlet in the compartment so I can use a heavy duty extension cord to plug into the 20 Amo outlet on the power post. Or if there isn’t one I have a splitter that can plug into the 50 Amp outlet to feed my 30 Amp circuit and the new 20Amp one. On its way to the basement I routed the Romex to the “living room” to feed an outlet that I use for a space heater during cold weather. It lets the 30 Amp system stay fully able to run the microwave, water heater etc. very happy with the result.