Looking for insight on RV 13.5kbtu AC

[SCmountainman]

Does anyone have real world average power consumption for 20-24 ft travel trailers running the rooftop ac units? Thinking of getting a camper, but wondering how many KWh per day folks average running the AC in the summer in the southeast USA. My uneducated guess would be around 10-12KWh per day assuming the AC units are around 1200 watts and in a smaller campers would run 10 hours total runtime per day? I have no idea, never owned a camper. Looking for advice. Would love to have it fully self contained and not have to use the generator much or at very least no generator at night.

I would install a soft start on the AC unit. Considering a 3-4000 watt inverter and 800AH of lifepo4, along with other supporting modifications, panels, controllers etc. Trying to budget and plan out total cost for camper+fully self contained boondocking power build.

Thanks!

 

[jimcalf]

Running off batteries, through my inverter (Victron Multiplus 24/3000) my 13.5kbtu Dometic Brisk II draws 12.5A when the compressor is running. That is accounting for inverter loss. How much will be used in a day? Depends on all the usual factors (temp, humidity, thermostat setting, sun, wind, etc._). My trailer is 23', so it cools pretty fast, and I have a softstart, but energy usage varies wildly depending on the circumstances. Don't shoot for averages, you'll be wrong a lot of the time. I have 460ah @ 24V, and it gets me through a night if fully charged on a hot, humid night. Getting it fully charged is the harder part. I can only fit 860W of solar, so... depends on how much time I have to run a generator.

 

[SCmountainman]

Running off batteries, through my inverter (Victron Multiplus 24/3000) my 13.5kbtu Dometic Brisk II draws 12.5A when the compressor is running. That is accounting for inverter loss. How much will be used in a day? Depends on all the usual factors (temp, humidity, thermostat setting, sun, wind, etc._). My trailer is 23', so it cools pretty fast, and I have a softstart, but energy usage varies wildly depending on the circumstances. Don't shoot for averages, you'll be wrong a lot of the time. I have 460ah @ 24V, and it gets me through a night if fully charged on a hot, humid night. Getting it fully charged is the harder part. I can only fit 860W of solar, so... depends on how much time I have to run a generator.

Thanks for your insight.

I assumed that the AC units are pretty hungry on RVs. As far as rooftop array is concerned, can you only fit 860 watts due to roof dimensions or weight bearing capacity? I have looked a a few campers and one had a rail already built into the roof for panels. Are your batteries lifepo4 or lead acid?

 

[Zwy]

Does anyone have real world average power consumption for 20-24 ft travel trailers running the rooftop ac units? Thinking of getting a camper, but wondering how many KWh per day folks average running the AC in the summer in the southeast USA. My uneducated guess would be around 10-12KWh per day assuming the AC units are around 1200 watts and in a smaller campers would run 10 hours total runtime per day? I have no idea, never owned a camper. Looking for advice. Would love to have it fully self contained and not have to use the generator much or at very least no generator at night.

I would install a soft start on the AC unit. Considering a 3-4000 watt inverter and 800AH of lifepo4, along with other supporting modifications, panels, controllers etc. Trying to budget and plan out total cost for camper+fully self contained boondocking power build.

Thanks!

I have a 9K btu roof air on my truck camper. It draws around 1200w with compressor running. I've run it on a 24V 280Ah LFP bank.

I have a 9K inverter mini split here and I've fabricated the outside mount for the condenser. I need to remove a bunk and install the evaporator and build a cabinet alongside that to house the microwave. I might not finish the project until fall or late summer.

If you search in the archives here, you will find many discussions concerning roof air units vs installing a mini split. If the mini split draws less than 600W, then I will be able to run around 8 hrs or more on just battery power vs the 4 hours on the roof air. Most members running a mini split are reporting 300 to 400W consumption.

If you have the option, buy without any roof air and add a mini split. I will be installing a fan in place of the roof air.

 

[SCmountainman]

I have a 9K btu roof air on my truck camper. It draws around 1200w with compressor running. I've run it on a 24V 280Ah LFP bank.

I have a 9K inverter mini split here and I've fabricated the outside mount for the condenser. I need to remove a bunk and install the evaporator and build a cabinet alongside that to house the microwave. I might not finish the project until fall or late summer.

If you search in the archives here, you will find many discussions concerning roof air units vs installing a mini split. If the mini split draws less than 600W, then I will be able to run around 8 hrs or more on just battery power vs the 4 hours on the roof air. Most members running a mini split are reporting 300 to 400W consumption.

If you have the option, buy without any roof air and add a mini split. I will be installing a fan in place of the roof air.

I’m familiar with mini splits, I have 2 at home and you are correct they don’t use much power at all. Mine are both 12kbtu and average 150-300 watts maintaining set point with 90 OAT and 70 IAT.

Most of the smaller campers don’t have a lot of room on the tongue to mount the condenser. Rear bumper maybe. I’m also researching VFD retrofit kits for conventional compressors. They are available for residential condensing units and $$. All campers in my area have roof air conditioning. Looking at on the lot units. Ordering a custom camper would probably take months. Hard to fathom no one has made a more efficient factory ac unit for campers and that all sizes have a 13.5k slapped on the roof. Even the tiny tear drop styles around here have a 13.5k.

 

[Bobert]

If you can figure out how to mount a high seer rated mini split on your camper you can pay for it with the batteries you don’t need and in some cases add 400watts of solar in the space it used to occupy. It’s a lot quieter too.

 

[jimcalf]

Thanks for your insight.

I assumed that the AC units are pretty hungry on RVs. As far as rooftop array is concerned, can you only fit 860 watts due to roof dimensions or weight bearing capacity? I have looked a a few campers and one had a rail already built into the roof for panels. Are your batteries lifepo4 or lead acid?

I only have 860W because that is all that will fit. I still have room to move around the roof for maintenance, but not much. Lots of obstructions when the roof is only 18' long x 7' wide, but you have a shower skylight, two vents, A/C, TV and radio antennas and vent stacks. Fitting panels is like playing Tetris. I've seen folks install raised rail systems that go above all the obstructions, which I admit is tempting, but a bit much for my use case in the east where boondocking is more the exception than the rule. If I lived out west where there is tons of BLM land, I think I'd consider a system raised above the roof. My batteries are a DIY LiFePO4 build with 16 x 230ah cells configured 8S into two 24V @ 230ah batteries in parallel. Total of about 11kwhr.

 

[Bobert]

I raised my array 8” by using brackets I made from discarded extruded aluminum bleachers. I purposely bracketed the roof space and left a gap exactly the same size as my panels so I can add 2 more if I get a mini split.

 

[jimcalf]

I raised my array 8” by using brackets I made from discarded extruded aluminum bleachers. I purposely bracketed the roof space and left a gap exactly the same size as my panels so I can add 2 more if I get a mini split.

If I find that this summer we boondock enough to justify swapping out the rooftop A/C for a mini-split, then I'll consider revamping my solar array. Removing the A/C unit from the roof would be a game changer for what I could fit. Still not convinced that I'll need it unless I can work out a way to camp out west a lot more.