Air compressor
I agree there isn't a specific compressor to use but myself I don't think the 12v type will bs able to keep the pressure and volume at about 40psi to sufficiently clear the lines. You may also want to read up on the Truma system here "https://www.truma.net/advice-blog/winterizing-your-truma-aquago-or-truma-combi". By the way, how do you like it? I've been reading up on them a bit but haven't heard first hand if they're worth the changeover.
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