9 cooling capacity, 10 heat pump in heating – Fieldpiece HG2 - HVAC Guide System Analyzer User Manual

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5.802 Condensing unit amps unknown, check

condensing unit amps:

e outdoor unit amp

draw was not measured.

5.803 High outdoor amp draw, probable exces-

sive compressor friction:

Check other possible

causes of high amp draw (low condenser airfl ow and
refrigerant overcharge) before condemning the com-
pressor. Check that condenser coils and fi ns are clean,
aligned and free of nearby obstructions.

5.804 Low outdoor amp draw, possible com-

pressor valve or motor problem:

Check the re-

frigerant charge before condemning the compressor.

5.9 Cooling Capacity

e heat rejection at the outside unit is another mea-

surement that gives indication of the health of the com-
pressor as well as other potential problems.

5.901 Condesner capacity OK:

e condenser is

delivering the proper capacity.

5.902 Low condenser capacity, check charge,

retest:

is unit is rejecting less heat than expected.

Check the refrigerant charge, repair if needed, and re-
test.

5.903 Low condenser capacity, check compres-

sor amps and coil saturation temperatures:

Full diagnosis of this situation requires a complete set
of data including compressor amps, high and low side
pressures, and liquid and suction line temperatures.

5.10 Heat Pump in Heating

Test the refrigerant charge for a heat pump in the sum-

mer in the cooling mode if possible. Th

is procedure checks

the heating capacity of the heat pump against the expected
capacity for the test conditions. In order to determine the
capacity of a heat pump, the airfl ow through the inside
coil must be directly measured with the TrueFlow®.

5.1001 Heating Capacity OK:

e heat pump is de-

livering the proper heating.

5.1002 Capacity unknown, check capacity:

TrueFlow inputs, outdoor unit entering temperature,
return plenum temperature, and supply plenum tem-
perature need to be measured before determining ca-
pacity.

5.1003 Low capacity, defrost outside coil or ad-

just charge and retest:

Verify that the outside coil

is not frosted or iced. Frost reduces the capacity of the
heat pump. If the unit is not frosted, adjust the refrig-
erant charge per the manufacturer’s specifi cation.

5.1004 High temp split, make sure strip heat is

NOT on:

Check amperage to the electric strip heat-

ers to verify they are turned off .