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Bredwagon's avatar
Bredwagon
Explorer
Jun 23, 2014

Ac unit bad?

Ok here is my question. I was running my ac today in my trailer. ( plugged into shore power). I noticed that the fan would slow down and then speed back up. Also when it slows down I could here a buzzing from the breaker panel. So I shut it off right away until I could get it checked out. Does it sound like ac is bad? The trailer is a 90s model and is still the orginal ac.- it was taken very good care of. Would it better to just replace the whole unit with a newer one? Thanks.

15 Replies

  • RoyB's avatar
    RoyB
    Explorer II
    Another possibility may be the battery system. Perhaps your battery has boiled out all of the battery fluids and the converter is seeing a very big load from the battery which is loading down your 120VAC coming from the shore power connection.

    We use our trailers connected to the garage 120VAC 15/20AMP receptacle but always keep a close watch on the 120VAC using one of those RV120VAC PLUG-IN VOLTMETERs.

    If the input 120VAC power is not with-in the "GREEN SAFE ZONE" displayed on the meter face we don't use our Air Conditioner.



    It is possible your converter was loading down your shore power big time trying to deal with your battery system.

    I would check the fluids in the battery and see what the DC VOLTAGE is at the battery terminals when you are connected to your house shore power. This should read 13.6VDC when you have shore power connected and 12.6VDC when the shore power is OFF and the battery is fully charged...

    Roy Ken
  • Age maybe a factor - but my AC is from 92 and it works fine albeit doesn't get used often and I clean/maintain it annually.

    If your sure your getting ample shore power then take off the shroud and inspect the unit .. clean both the condenser and evaporator coils (use forum search feature for how to clean evaporator coils) .. while your up there inspect the start and run capacitors sometimes a bad one can be identified because of smell or deformation - they don't cost much to replace. Check the fan motor .. older units may have fan motor that requires periodic lubrication (mine has oil hole). Also - clean the air intake filters located inside the rig.
    Those are the free/inexpensive things to check out. Compressor issues are big ticket and would usually require replacement of unit.
  • I would replace a 20 year old model rather than a rebuild myself. assuming it is a goner.
    bumpy
  • I would start by monitoring the voltage while running the AC. What kind of "shore power" are you plugged into -- home 15 amp outlet or 30 amp RV? Fan slowing down maybe an indicator that volts are sagging. If the voltage falls below 109 when running AC I would recommend turning AC off and finding another site with better power supply.

    When I run my AC I monitor voltage using a Kill A Watt http://www.amazon.com/P3-International-P4460-Electricity-Monitor/dp/B000RGF29Q/ref=sr_1_2?ie=UTF8&qid=1403515563&sr=8-2&keywords=kill+watt+meter

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