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Trane Tests Board

Discussion in 'Commercial' started by Zman, May 25, 2017.

  1. Zman

    Zman Hanging by a Thread

    Messages:
    524
    Location:
    The "I know a Guy" State
    Anyone familiar with the Trane RTU Test Board?I ran on the cooling terminals to test the circuits.Both stages (compressors),kick in,but neither Condenser fan motor ran.The Blower fan runs,but compressors kick off shortly thereafter.I can't believe they shut off on High Head from no Condenser fans running,it was too quick,and it was cold and rainy.Then it poured out,so I packed up and left.I Believe in test mode,it bypasses the economizer function,not sure why the cond fans never ran.Call tech support tomorrow when I return,just not sure of the test function operation.Never got my gauges out,maybe low pressure leaker,but I still think those fans should of ran instantaneously with the compressors.
     
  2. Zman

    Zman Hanging by a Thread

    Messages:
    524
    Location:
    The "I know a Guy" State
    Never Mind:Just got done reading the test mode service manual,says cond fans will only run if outdoor air temp is within set point value.Quess I get to start my test all over again tomorrow...if it don't Rain...and if it warms up!
     
  3. otto

    otto Bakery Chef

    Messages:
    19,790
    Location:
    in a van down by the river
    Yes, the condenser fans will run depending on the outdoor temp. Leaving the jumper on will only run the different stages for a short time. Taking the jumper off during any given test will keep it in that test section for one hour, I think. I like to jumper to start the test then remove the jumper. This starts the blower. Jumper again to start testing the economizer and remove the jumper to see that the econ opens & closes. Jump again to start the 1st stage compressor, remove the jumper to check operation. If it's cold outside the fan should come on. If you have one fan it should run. If you have two fans and it's cold, one should come on and the other will stay off. There is an OA sensor to the right and below outside the control panel. You can pull it out of its rubber holder and hold it in your hand to warm it up. This will stop the compressor and fan allowing a moment for the off fan to stop spinning backwards then restart with both fans on. This may be different for more than two fans. Jumper again to start 2nd stage compressor. Be sure to reinstall the OA sensor back into the rubber holder as you found it, this is VERY important. Jumper again for the heat and again for 2nd stage heat then one more time to conclude test.

    You can also buy a decade box to give different resistance jumper to the test terminals to test any given stage.
     
    ISOTHERMAL, Zman, LemonWizard and 2 others like this.
  4. LemonWizard

    LemonWizard Blinky Lights Wizard

    Messages:
    1,972
    Location:
    Ohighyo
    And just remember























    It's hard to stop a trane. :tard:
     
  5. Chuck

    Chuck The Other Dude

    Messages:
    7,507
    Location:
    LAX
    It's even harder to start one :D
     
  6. Zman

    Zman Hanging by a Thread

    Messages:
    524
    Location:
    The "I know a Guy" State
    You explained it better than Manual,the sensor tip is a Great Idea.Was there for no A/C,i think low Pressure,got interrupted by rain.Thank You.
     
  7. Zman

    Zman Hanging by a Thread

    Messages:
    524
    Location:
    The "I know a Guy" State
    I guess that's one way to stop a Trane,take away it's Fuel.
     
  8. ISOTHERMAL

    ISOTHERMAL senior member

    Messages:
    33,652
    Location:
    Green Acres
    Yep, What Otto said.
    Also you can NOT have a signal from the T-stat to put the unit into test mode. (I normally disconnect R).
    As Otto said, when you have 2 condenser fans the 2nd cycles with the OD temp.
    Along with the OD Temp sensor, there is a relay located on the right side of the control panel, it is below the condenser fan capacitors, behind the terminals that you are jumpering to put it in test mode.
     
    Zman and Texas-Tech like this.
  9. pintofstout

    pintofstout New Member

    Messages:
    1,475
    Location:
    Olean, NY
    Use a quarter to cycle through test modes. That way you can press hard and use the knurling on the quarter to scrape the rust off the screws.

    Also the two big fat relays at the bottom of the board run the fan, just plane Jane spade connectors on it. Easy to jump, even in rain...

    Sent from my iPhone using Tapatalk
     
    Zman likes this.