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505331M 06/09
XP19 Field Operational Checklist
26
Unit Readings
Cooling***
Heating***
Y1 − 1st-
Stage
Expected results
during Y2 demand
(Toggle switch On)
Y2 − 2nd-
Stage
Y1 − 1st-
Stage
Expected results
during Y2 demand
(Toggle switch On)
Y2 − 2nd-
Stage
Compressor
Voltage
Same
Same
Amperage
Higher
Higher
Condenser Fan motor
Amperage
Same or Higher
Same or Higher
Temperature
Ambient
Same
Same
Outdoor Coil Discharge Air
Higher
Lower
Compressor Discharge Line
Higher
Higher
Indoor Return Air
Same
Same
Indoor Coil Discharge Air
Lower
Higher
Pressures
Suction (Vapor)
Lower
Down
Liquid
Higher
Higher
Note − Heat pump may have a low ambient control or DCB that locks in second stage below its set point. It may be necessary to remove a wire from
the control when performing this check out.
**
On the XP19 units, the Lennox System Operational Module controls the 2nd stage solenoid coil in compressor.
***
Cooling Mode Operation − Block outdoor coil to maintain a minimum of 375 psig during testing.
Heating Mode Operation − Block indoor coil to maintain a minimum of 375 psig during testing.
XP19 Start−Up and Performance Checklist27
Customer
Address
Indoor Unit Model
Serial
Outdoor Unit Model
Serial
Notes:
START−UP CHECKS
Refrigerant Type:
Rated Load Amps
Actual Amps
Rated Volts
Actual Volts
Condenser Fan Full Load Amps
Actual Amps:
COOLING MODE
Vapor Pressure:
Liquid Pressure:
Supply Air Temperature:
Ambient Temperature:
Return Air Temperature:
HEATING MODE
Vapor Pressure:
Liquid Pressure:
Supply Air Temperature:
Ambient Temperature:
Return Air Temperature:
System Refrigerant Charge (Refer to manufacturer’s information on unit or installation instructions for required subcooling and approach
temperatures.)
Subcooling:
A
B
=
SUBCOOLING
Saturated Condensing Temperature (A)
minus
Liquid Line Temperature (B)
Approach:
A
B
=
APPROACH
Liquid Line Temperature (A)
minus
Outdoor Air Temperature (B)
Indoor Coil Temp. Drop (18 to 22°F)
A
B
=
COIL TEMP DROP
Return Air Temperature (A)
minus
Supply Air Temperature (B)
