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A/C start-up

Start with knowing if you have proper airflow.

Measure supply pressure,return pressure, find your total external static pressure and check the blower performace chart.

Then, only then can you take all these measurements.
Air entering the evaporator.
Air leaving the evaporator.
air entering condenser.
air leaving condenser.
entering wetbulb temp.
liquid line leaving condenser.
liquid line entering evaporator.
suction line temps at the evaporator.
suction line temps at the condenser.
compressor amps and voltage.

Take notes and see if your superheat and subcooling is where it should be.once she dail in then check to see what btus you are getting.

CFM X enthalpy x 4.5=btu.

Once you comment yourself to taking all these measurement
it will become easier to do.
It also help paint a bigger picture that will help with design and setup on all your other installation.


  • Jim PompettiJim Pompetti Member Posts: 552
    A/C start-up

    Can anyone help me , with a A/C start check list for start ups
  • mtfallsmikeymtfallsmikey Member Posts: 765
    Off the top of my head

    What's left of it that is:
    Compressor amp draw,
    Condenser fan motor amp draw,
    Fan motor amp draw,
    Refrigerant charge,
    Reversing valve operation (if applicable),
    Supply discharge air temp,
    Condensate drain operation,
    Thermostat operation-all modes,
    Refrigerant leak detection,
    Record all operating parameters-place in owner's manual.

    I'm sure this is not complete....not a sermaon, just a thought...mfm
  • Jim BergmannJim Bergmann Member Posts: 24
    Check Sheet

    Here is a sheet and accompanying instructions I developed. If you want to PM me I will send as a word doc for editing, I could not upload it here for some reason

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