Forum Discussion

DLanc's avatar
DLanc
Explorer
Jun 17, 2014

AC bogs down when light is turned on..?

brand new to camper ownership and this sight. I am looking over a fixer upper TT to purchase. I know very little about campers so PLEASE HELP...!

I have plugged the camper in to my house 110v plug. When testing the lights, every time I turn one on the others go a little more dim...?

I turn on the AC, it runs pretty good, it cooled down the 97 deg interior rather quickly. BUT... while the AC is running I turn on a light switch the AC bogs down and hums quietly. click the light off and back on the AC comes up to speed blowing cold air once again.

Now I have 1 light on and AC blowing hard, then I turn on a second light the AC bogs down a hums again. At this point I have to turn off both lights to get the AC to run normally. To run the AC and the two light you must turn both lights on, off then on simultaneously. cRaZy HuH???:?

Any and all comments and info would be greatly appreciated. I want a project TT not a money pit TT

V/R
DL

10 Replies

  • beemerphile1's avatar
    beemerphile1
    Explorer
    Jun 18, 2014
    What amperage circuit is it plugged into? Are you using an extension cord? If so, how long and what gauge?

    A park model might have 110vac lights. I'm guessing that it does and you have one of two issues;
    1. low incoming voltage
    2. bad, corroded, or loose connections in the electrical supply.
  • DLanc's avatar
    DLanc
    Explorer
    Jun 18, 2014
    thank you for the info and suggestions.
    all I know at this point is the TT make is a 2005 forest river "park model". its not a self contained TT. there are no obvious labels that tell me what the model is...? any clues where to look. I discovered a label at the drivers front corner but its not legible; I did pull what I think would be the vin(?) 4X4TWDH226T133711.

    The layout has 2 bunks to one side and bathroom at the rear, no slide out, standard couch, dining table, kitchen and front bedrm. Its about 30' long.

    Again, the only experience I have is from what I've read on forums and articles. I'm just looking this one over to get a fixer upper starter TT; you know, just as a starter to see if we like moving up to the next level of camping.
    thanks again
  • beemerphile1's avatar
    beemerphile1
    Explorer
    Jun 18, 2014
    You are getting educated guesses because you have given no information.

    First, tell us what year, brand, and model RV. Are these lights 110vac or 12vdc. Always give as much information as possible when asking questions. Modern RVs all have 12vdc lights but many older RVs used 110vac lighting.
  • nomad297's avatar
    nomad297
    Explorer
    Jun 18, 2014
    calamus wrote:
    you may be able to just unhook (the battery) and not use it at all if you will have shore power at all times? Just a thought.


    Not a good idea if the trailer will be towed. There will be no power for emergency braking.

    Bruce
  • calamus's avatar
    calamus
    Explorer
    Jun 18, 2014
    While I agree with you converter being out of whack. I dont know about the battery. Our Layton has sat at the lake for years and does not even have a battery in it, all the 12 volt lights pump etc. work fine, it may be your battery is causing the problem, you may be able to just unhook it and not use it at all if you will have shore power at all times? Just a thought.
  • westend's avatar
    westend
    Explorer
    Jun 17, 2014
    The easiest way to test the converter is to use a hand held multimeter and measure voltage across the battery terminals. At rest a fully charged battery will be 12.6-7V. With the converter powered you should measure at least 13.5V across the terminals.

    Telling us what trailer you have, it's year and the make/model of the converter will bring more advice.
  • DLanc's avatar
    DLanc
    Explorer
    Jun 17, 2014
    Thank you all for the VERY quick response. I will swap out the battery tomorrow and give it a try.
    BTW in attempting to do some troubleshooting I hooked the TT to my 5500Watt generator. It didnt change any of the symptoms.

    I have a question that may seem elementary to y'all but... please tell me where and how to test the converter or recommend a forum link for testing the converter.

    Again, thanks a million.
  • westend's avatar
    westend
    Explorer
    Jun 17, 2014
    The battery is shot. If you had a fully charged battery, the lights would not dim.

    It may be that when you power a light, the converter is trying to power that additional load, drawing more 120V. When the converter draws that load, there is not enough current available for the air conditioner. Don't continue to operate it like this. There is a chance to damage the AC.
  • old_guy's avatar
    old_guy
    Explorer
    Jun 17, 2014
    how big is the amps on that house circuit? it might be border line and using too many amps when using the A/C. that would cause the lights to dim. you really need a 30 amp circuit to run a TT faith the air going and still use the lights. normally any thing less than 30 will make the a/c hum or not work at all.
  • hmknightnc's avatar
    hmknightnc
    Explorer
    Jun 17, 2014
    12volt DC lights should have exactly zero impact on AirCond operation if plugged into 110volt AC and your converter and battery are working properly and in good shape. With your description it is really hard to tell but I'm guessing your converter is not properly supplying 12volt so the battery is picking up the load in a depleted state causing your AirCond control voltage to get low enough to cause it to act funny. Your lights are 12volt DC Powered, obviously your AirCon is 110volt AC but it's control circuitry is 12volt DC.
    - check your converter is putting out around 13.6 volts to the battery
    - verify your battery is in good condition by having it load tested.

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