Forum Discussion

gjleno's avatar
gjleno
Explorer
Sep 11, 2013

roof ac or dash air

If you run generator and run roof air is it less costly than running dash air and can dash air keep 40ft. motorhome cool.

14 Replies

  • I saw figures for dash A/Cs from 4k to 48kBTU. I throw in the towel on that one.

    Since I live in Texas, the last motorhome I rented, I just used both the dash air and the roof air with the generator running. It cost me about 1 MPG, but kept the complete rig decently cool in 100+ degree weather.
  • JaxDad's avatar
    JaxDad
    Explorer III
    I think a few folks need a course in math. A standard F-series dash a/c is a little more than 3 times more capacity than a roof-top unit is.
  • It is supposedly cheaper to run the generator and roof air. Also, I don't think the dash air would come close to cooling a 40 ft MH. It would probably cool the driver compartment ok with dash air but not the rest of the unit. Too much cubic footage and too little air volume.
  • Dash air is great for keeping driver cool.........the rest of MH. Not so much.

    Pinching pennies and RV's is a conundrum. :B

    Turn on the gen, turn on the A/C unit and make everyone happy while traveling.
    Otherwise it can get real crowded up there by the dash.

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