2019 ProMaster Class B RV Outfitting With 12V DC Air Conditioner Rooftop Unit

Published 08/19/2025

Question:

I’m outfitting a 2019 ProMaster for weekend boondocking. Will the Velit 2000R 8k BTU keep it comfortable without shore power?

asked by: Brian

Expert Reply:

Brian, you’re right in the sweet spot. The Velit 8,000 BTU AC Unit # VE87QV runs directly on 12V and sips as little as 250 watts in Eco mode. For a ProMaster, 8,000 BTUs is plenty for cooling the living area, especially if you insulate well and use window covers.

How many batteries are you planning to run? That’ll help estimate hours of cooling. One wouldn't last that long, but a couple wired in parallel will give you several hours of AC use if not more. If lithium, you can get closer to 10-15 hours of run time depending on battery ah rating.

Other ProMaster or camper van owners - what’s your experience with off-grid AC systems?

expert reply by: Andrew N