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Wheresmyhammock's avatar
Wheresmyhammock
Explorer
Aug 26, 2017

15k BTU AC with 30amp or 2800 Onan Generator

Picking up our new class b on Thursday! Can.Not.Wait. But one thing is gnawing. Service guy says it's a-ok to upgrade the AC to a Coleman Mach 15 (no heat pump) + a "hard start" kit so it will play nicely with the onboard Onan RV QG 2800 generator.

We plan to drive with the gennie and ac on most of the time for pups until the Texas heat has passed, but a little worried about the longevity of both given draw. Plugged in or with generator, is 15000 BTU too much for the 30 amp Van?

Appreciate any insight anyone might have?

9 Replies

  • Puddles's avatar
    Puddles
    Explorer
    Sep 02, 2017
    MrWizard wrote:
    I think you could run a 9k or 11k inside that class B and stay COLD

    people cool 30ft RV with a 13k, IMO a 15k is overkill in 'B'

    Texas is hot but so is So Calif, we are forecast for 110* this week


    X2
  • Wheresmyhammock's avatar
    Wheresmyhammock
    Explorer
    Aug 27, 2017
    We put the kabosh on the upgrade and opted for newer Omni directional grille. can always upgrade later if need arises. Thanks for great insights!
  • MrWizard's avatar
    MrWizard
    Moderator
    Aug 27, 2017
    I think you could run a 9k or 11k inside that class B and stay COLD

    people cool 30ft RV with a 13k, IMO a 15k is overkill in 'B'

    Texas is hot but so is So Calif, we are forecast for 110* this week
  • Dennis12's avatar
    Dennis12
    Explorer
    Aug 26, 2017
    Put it to the test while the dealer is standing there for a while. Turn AC on as high as possible just enough to kick in the compressor, when it kicks out turn it down a little more to get it to put another load on it and keep going doing the same. I would definetly go with the 15,000.
  • Wheresmyhammock's avatar
    Wheresmyhammock
    Explorer
    Aug 26, 2017
    Appreciate the replies! Definitely on the fence about the 15,000 btu vs 13,500... but get overheated so easily with broken body thermostat. ??
  • marcsbigfoot20b's avatar
    marcsbigfoot20b
    Explorer
    Aug 26, 2017
    I have a Dometic 13.5 and an Onan 2500 LP (propane) which is the same gen as the 2800 just less power due to propane vs gasoline. Runs my AC just fine in 120 degrees.

    These gens are rated as minimum 2800 watts running or 2500 LP per the Onan spec at 77 degrees and 500 ft. There is no surge rating.

    After installing the micro air easy start, it's hard to even tell when the compressor kicks on.
  • LadyRVer's avatar
    LadyRVer
    Explorer II
    Aug 26, 2017
    I had a Class B with a 2800 Onan and the 13.5 ac was enough for it. I don't think I would have wanted to upgrade to a 15 with the 2800 Onan. Just my thought.
  • Itchey_Feet's avatar
    Itchey_Feet
    Explorer
    Aug 26, 2017
    have a polar cub (I think 900) way plenty for us and we have more area than a "B". JMHO
  • azrving's avatar
    azrving
    Explorer
    Aug 26, 2017
    Seems like a 13,500 would be plenty for that genny. It may be 2800 but generators are usually listed at surge not running watts. I also wonder if the dealer would have a tendency to tell you what ever they think you want to hear. CW told my son his 3/4 CTD CC could pull over 15K FW then said it would pull anything on the lot.

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