Can I run a 12V van air conditioner off my existing house batteries?

Only with a bank, cable and fusing designed for it. A 12V rooftop unit can draw up to 58 to 62 amps continuously, and the manufacturer warns that inadequate electrical connections can cause serious equipment damage. A 48V unit draws roughly 15 amps for the same or greater cooling.

How big a battery bank do I need to run van air conditioning overnight?

Ten kilowatt-hours is the practical minimum and fifteen gives real margin. Runtime depends on insulation, outside temperature, humidity and shade, and 48V units go considerably further per kWh than 12V units.

Is a rooftop or mini split air conditioner better for a van?

Rooftop units are self contained and fit a standard 14 x 14 inch opening. A back-pack mini split separates the condenser from the evaporator, which frees roof space and is generally quieter inside, but requires mounting two units and routing a hose set.

Will a heat pump replace a diesel heater in a camper van?

In mild weather yes; these heat pumps are designed as a primary heat source and the Webasto Cool Top Trail 36G operates from 23F to 122F. In deep cold a fuel-fired heater is better because output does not fall with ambient temperature and it draws only 6 to 26 watts.

Do van air conditioners ship charged with refrigerant?

Yes, all of these units ship prefilled. Climate Command heat pumps use R-410A, the RTAC and BPAC units use R-134a, and the Webasto Cool Top Trail 36G uses R-32. Units ship LTL freight on a pallet.

Van Air Conditioners | 12V & 48V Rooftop AC and Heat Pumps

12V & 48V Van Air Conditioners and Heat Pumps

Air conditioning is the hardest thing to add to a van, because it isn't really an A/C decision — it's a battery, roof space, and insulation decision wearing an A/C costume. We stock DC units only: no generator, no shore-power-required rooftop box. That means Climate Command's 12V and 48V rooftop air conditioners and heat pumps (RTAC12, RTAC48, RTHP12, RTHP48), the 12V BPAC12 back-pack mini split for builds that can't give up roof space, and the Webasto Cool Top Trail 36G — a 48V self-contained heat pump rated to run from 23°F to 122°F. For custom split systems we carry Red Dot and Webasto Capri rooftop condenser units at the component level. Below is the sizing math we walk customers through in the shop before they spend $1,100 to $1,900 on a unit and another few thousand on the batteries to run it.

How to Choose a Van Air Conditioner

1. The voltage decision drives everything downstream

Same cooling, wildly different current:

Unit	Type	Cool BTU	Heat BTU	Max current	Airflow	Weight
RTAC12	12V rooftop A/C	10,000	—	up to 58 A	265 cfm	49 lb
RTAC48	48V rooftop A/C	12,000	—	up to 15 A	265 cfm	49 lb
RTHP12	12V rooftop heat pump	11,500	8,500	up to 62 A cool / 55 A heat	323 cfm	73 lb
RTHP48	48V rooftop heat pump	13,500	10,500	up to 16 A cool / 14 A heat	323 cfm	73 lb
BPAC12	12V mini split (back-pack)	12,500	—	up to 60 A	353 cfm	41 lb + 13 lb
Webasto Cool Top Trail 36G	48V rooftop heat pump	11,600	11,600	15.0–30.6 A cool / 11.9–26.2 A heat	353 cfm (max)	89 lb

Look at RTAC12 versus RTAC48: 58 amps versus 15 amps for more cooling. That's why every serious off-grid A/C build we do now is 48V, and why we sell the EcoFlow 48V Power Kit line alongside these units. If you're already committed to a 12V house system and don't want to change it, the 12V units work — you'll just need heavy cable, serious fusing, and a bigger bank.

2. Size the battery bank before you size the BTUs

Rough shop math: a 12V unit at ~58 A is roughly 700 W while the compressor runs. Assume it runs 50–70% of the time on a hot, humid night and you're looking at 4–6 kWh overnight. That's why our standing recommendation for pairing a rooftop A/C with an EcoFlow Power Kit is a 10 kWh kit minimum, 15 kWh if you want margin. On a 48V unit drawing ~15 A (about 720 W but at a quarter the current), the wiring gets sane and the same bank goes considerably further because you're not fighting resistance losses in a 12V run.

The 48-Volt Air Conditioner Cable (20 ft, 4-post to bare wire) connects the A/C directly to a Power Hub battery port at the full 100 A @ 48V — this is the clean way to wire a 48V unit and it keeps your distribution panel's DC output free.

3. Rooftop or mini split?

Rooftop (RTAC/RTHP/Cool Top Trail) fits a standard 14" x 14" RV opening, which is the same cutout as a roof fan — so many builds swap the fan location or add a second cutout. Check mounting surface thickness: RTAC units allow 1.5"–3.5"; the Cool Top Trail wants 0.98"–2.75" roof thickness and a 15.75" hole (or 14" with the included framing). Rooftop units are self-contained and prefilled with refrigerant.

Mini split (BPAC12) splits the condenser (31.75" x 15.6" x 7.5", 41 lb installed) from the evaporator (23.6" x 11.6" x 7.75", 13 lb), joined by a 9' prefilled hose set. Choose it when your roof is already full of solar and a fan, or when you want the evaporator inside a cabinet with ducted outlets. Note: the BPAC12 temperature display reads in Celsius only.

4. Heat pump or A/C only?

The heat pumps (RTHP12, RTHP48, Cool Top Trail 36G) are designed to be a primary heat source, not a supplement — 8,500 to 11,600 BTU of heat. In shoulder season, moving heat is far more efficient than making it. But heat pump capacity falls as outdoor temperature drops, and none of them will beat a fuel-fired air heater at 15°F, where a 2 kW Webasto or Espar keeps working on almost no electricity. The best all-season van we build has both: a heat pump for 35–60°F, a diesel or gas heater below that.

5. Insulation is part of the unit's spec

Every manufacturer here says the same thing: BTU ratings assume a properly insulated vehicle. An uninsulated cargo van with a 13,500 BTU heat pump on the roof will run the compressor continuously and still lose. Do the Thinsulate first. It's cheaper than the batteries you'd otherwise need.

6. Freight, weight, and roof structure

These ship LTL freight on a pallet due to size and weight, with freight charges applied at checkout — international shipments to Canada only. Installed weights run 49 to 89 lbs, which is real load on your roof and on your rack layout. Plan the reinforcement around the cutout, and remember the unit's weight sits high, which affects handling more than the number suggests.

Frequently Asked Questions

Can I run a 12V air conditioner off my existing house batteries? Only if the bank and wiring are built for it. A 12V rooftop unit can draw up to 58–62 amps continuously; that's not a load you tap off an existing accessory circuit. Climate Command warns explicitly that these units require significant amp draw and that improper or inadequate electrical connections can cause serious equipment damage. Size the cable, the fuse, and the bank deliberately — or go 48V and cut the current by roughly four.

How long will an air conditioner run on a 10 kWh or 15 kWh battery kit? On a 48V unit, most owners get through a full night on 10 kWh with the fridge running, and comfortably on 15 kWh. On a 12V unit, expect meaningfully less because you're moving four times the current through the same system. Real runtime depends on insulation quality, outside temperature, humidity, whether the van is shaded, and how cold you set it.

Rooftop or mini split — which is quieter inside? The mini split, generally, because the compressor and condenser sit outside the sleeping space rather than in a box directly over your head. The trade is more install work: two units to mount, a 9' hose set to route, and condensate to manage. All these units use inverter scroll compressors with brushless condenser and evaporator fans, which are dramatically quieter than legacy RV rooftop units.

Will a heat pump replace my diesel heater? In mild weather, yes — the RTHP and Cool Top Trail units are designed as a primary heat source, and the Cool Top Trail is rated to operate from 23°F to 122°F. In real cold, no. Heat pump output drops with ambient temperature and it costs battery to run; a fuel-fired heater draws 6–26 W and doesn't care how cold it is. Most four-season vans we build carry both.

What refrigerant do these use, and do they ship charged? All ship prefilled with refrigerant. Climate Command RTHP units use R-410A; the RTAC and BPAC units use R-134a; the Webasto Cool Top Trail 36G uses R-32. Prefilled means no vacuum-and-charge step on a self-contained rooftop install.

Can I use the condenser units you sell to build my own system? Yes, that's what the Red Dot (R-6160-0P, R-6260-1P, R-4500-8P) and Webasto Capri (62U00025456E) rooftop condenser units are for. They're components, not complete systems. The Red Dot R-6160-0P, for example, is 24,000 BTU at 12 A @13.6 VDC, and Red Dot specifies pairing with an R-6840/R-7830/R-9755/R-8500/R-8545 evaporator under 20,000 BTU and a Sanden SD7H15 compressor with the pulley matched to your engine and the clutch matched to your electrical system. Drier and hose kits sold separately. This is engine-driven-compressor territory — know what you're building before you order.