Maryland Water Furnace Series 5 High Temp In and Out

Discussion in 'Maintenance and Troubleshooting' started by Buck Wilde, Sep 4, 2018.

  1. Buck Wilde

    Buck Wilde New Member

    I have a Series 5 Water Furnace that has produced nothing but high electric bills since it was installed a few years ago. The installer maintained it for the first few years and always blamed it on insulation, compressor settings etc.. I finally had another company look at it and they said the temperature in was 95.4 and the temperature out was 102. PSI is 10 our and 12 in. They said it may have air in the lines removed and additional water added. However, they said it might not be worth doing until they can determine the number of wells and their depth because the system might not have enough wells. I'm still trying to track down the number and depth of the wells.

    Is there any sure fire way to tell if a system doesn't have enough wells or is there an in expensive way to bleed the system or check for air? I don't want to waste $750 to have it pumped/vacuumed out and then realize I am a well short.
    Last edited: Sep 6, 2018
  2. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    whether you have enough loop or not, air can look loops and explain what you see. But there is more.

    What is your model number, and was it running in first or second stage (if you have a 2 stage unit)

    Your temperature is a bit too high and your pressure drop does not indicate enough flow. Delta T was 6.6F, and 2 PSI indicate about 8.5 gpm flow through your heatpump

    heat rejection = 6.6F delta T x 8.5 gpm x 485 = 27,208 BTU/h

    Pretty low unless you had a 2 ton unit running in first stage, which you don't have, since then your pressures and temperatures would be different.

    There is something wrong with the refrigerant circuit, since the capacity is low.

    None of the companies followed the basic steps to check quickly what is wrong....
  3. Buck Wilde

    Buck Wilde New Member

    Model is NDV049F111CTL0AA.
    Not sure what stage it was in at the time.
    3 vertical wells that are 200' x 1".
    Closed loop.
    1 circulator pump.
    House has 3 Zones. 2 zones on main level covering ~2,500 sq. feet, no zone in the basement but it has vents ~1,4oo sq. feet, 1 zone in the up stairs loft which is ~500 sq. feet.

    Last edited: Sep 6, 2018
  4. docjenser

    docjenser Well-Known Member Industry Professional Forum Leader

    Your NDV049 should reject about 45,000 BTU in first stage, and around 60,000 BTUs in second stage. You are rejecting 27,000 BTUs.

    So assuming that your unit was running in 1st stage, it is still way less than it should be. There is something wrong with your refrigerant circuit. Have them check refrigerant levels as first steps.
  5. Buck Wilde

    Buck Wilde New Member

    Thanks for the insight.
    Here is some more info based on another visit by the HVAC company. This was taken while the unit was in 2nd stage.
    Compressor RLA 21.1
    Actual 14.8
    Discharge Pressure 355
    Suction Pressure 120
    Liquid Line Temperature 108 Degrees
    Sub Cooling 0
    Evaporator Temperature In 53.1 Degrees
    Evaporator Temperature Out 70 Degrees
    Evaporator Split 17 Degrees
    Ambient Temperature 75 Degrees
    Evaporator Fan FLA 4.0
    Evaporator RLA 2.3
    Loop PSI In 15
    Loop PSI Out 12
    Loop Temp In 93.6 Degrees
    Loop Temp Out 105.1 Degrees

    I'm being told again that it's likely a loop issue.
    Last edited: Sep 19, 2018

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