Loop temperature problems

Discussion in 'Maintenance and Troubleshooting' started by duglin2, Feb 20, 2013.

  1. duglin2

    duglin2 New Member

    My unit was working great a couple of months ago, but I am experiencing some issues now that the weather is colder. I began getting a "Compressor Low Suction Temp" fault. My unit, a Daikin McQuay 4 ton, will reset once and then shut off compressor on second fault. I originally suspected low glycol level, it was around 10%, but now I have it at 30% and am still getting the same fault. I am trying to check the water temps but don't have a probe type thermometer. I have an infrared gun. Will checking the fitting temps with that be accurate?
  2. Rgausman

    Rgausman Member

    Sorry I can not comment on the refrigeration side of things... What reading are you getting with the IR? They are not accurate compare to a temp probe which can be inset directly into the ground loop fluid. FWIW, I purchased another temp probe and found that my old probe was reading 3 degrees higher. You should always test the calibration of your temp probe with insulated container full of ice water. Bob G.
  3. duglin2

    duglin2 New Member

    Thanks. I'm thinking that either my gun is not sensitive enough or checking the surface temperature of the fittings is not an accurate way to check water temps. I get readings of 40.5 EWT and 39.5 LWT. I have ordered a probe thermometer and am just hoping to nurse the system along until I receive it. Thanks again.
  4. ACES-Energy

    ACES-Energy Member Industry Professional Forum Leader

    Need more info

    1) Where you live
    2) Heat loss/gain calculations for your home
    3) Brand, size (model) and type of heat pump
    4) Type of loop field (open/closed/vertical/horizontal) size and design parameters
    5) Average cost/Kwh of electricity and consumption
    6) Entering and leaving air temperatures (EAT, LAT) measured immediately upstream and downstream of the heat pump
    7) Entering and leaving water temperatures (EWT, LWT) measured at the heat pump(s)
    8) Percent of load to be covered by geo and balance point
    9) Installers assessment of your systems operation.
    10) Projected operating costs, actual operating cost and previous heating and cooling costs

    Pressurized or non-pressurized?

Share This Page