Start-Up And Performance Checklist - Lennox XP14-018-230-06 Nstallation And Service Instructions

SEQUENCE OF OPERATIONS
This is the sequence of operation for XP14 series units.
The sequence is outlined by numbered steps which
correspond to circled numbers on the adjacent diagram.
The steps are identical for both cooling and first stage
heating demand with the exception reversing valve L1 is
energizedduringcoolingdemandandde-energizedduring
heating demand.
NOTE- Transformer in indoor unit supplies power (24 VAC)
to the thermostat and outdoor unit controls.
COOLING:
Internal thermostat wiring energizes terminal O by cooling
mode selection, energizing the reversing valve L1.
1. Demand initiates at Y1 in the thermostat.
2. 24VAC energizes compressor contactor K1.
3. K1‐1 N.O. closes, energizing compressor (B1) and
outdoor fan motor (B4).
END OF COOLING DEMAND:
1. Demand is satisfied. Terminal Y1 is de‐energized.
2. Compressor contactor K1 is de‐energized.
3. K1‐1 opens and compressor (B1) and outdoor fan
motor (B4) are de‐energized and stop immediately.

Start-Up and Performance Checklist

Job Name
Job Location
Installer
Unit Model No.
Nameplate Voltage
Rated Load Ampacity
Maximum Fuse or Circuit Breaker
Electrical Connections Tight? -
Indoor Blower RPM
Vapor Pressure;
Leak Checked? - Properly Insulated? -
Refrigerant Lines:
Fully Opened? - Caps Tight?
Service Valves:
SEQUENCE OF OPERATION
-
Heating Correct?
Serial No.
Compressor Amperage:
Indoor Filter clean? -
S.P. Drop Over Indoor (Dry)
Cooling Correct?
FIRST STAGE HEAT:
Internal thermostat wiring de-energizes terminal
heating mode selection, de-energizing the reversing valve
L1.
See steps 1, 2 and 3.
END OF FIRST STAGE HEAT:
See steps 4, 5 and 6.
DEFROST MODE:
When a defrost cycle is initiated, the control energizes the
reversing valve solenoid and turns off the condenser fan.
The control will also put 24VAC on the "W1" (auxiliary heat)
line. The unit will stay in this mode until either the coil
sensor temperature is above the selected termination
temperature, the defrost time of 14 minutes has been
completed, or the room thermostat demand cycle has
been satisfied. (If the temperature select shunt is not
installed, the default termination temperature will be 90°F.)
If the room thermostat demand cycle terminates the cycle,
the defrost cycle will be held until the next room thermostat
demand cycle. If the coil sensor temperature is still below
the selected termination temperature, the control will
continue the defrost cycle until the cycle is terminated in
one of the methods mentioned above. If a defrost is
terminated by time and the coil temperature did not remain
above 35°F (2°C) for 4 minutes the control will go to the
30-minute Time/Temperature mode.
Job no.
City
City
Service Technician
Supply Voltage (Unit Off)
Outdoor Coil Entering Air Temp.
Outdoor Fan Checked?
-
Voltage With Compressor Operating
Calibrated? -
-
Page 47
O
Date
State
State
-
THERMOSTAT
Properly Set? - Level? -
XP14 SERIES
by