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push pin a couple fins to the right or left of the original
hole and re−insert the pin.
9 PINS USED ON −048
AND −060; 6 PINS ALL
OTHERS
PUSH PIN
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MESH
SCREEN
Figure 33. Cleaning Debris from Mesh
THERMOSTAT OPERATION
Though your thermostat may vary somewhat from the
description below, its operation will be similar.
Temperature Setting Levers
Most heat pump thermostats have two temperature
selector levers: one for heating and one for cooling. Set the
levers or dials to the desired temperature setpoints for both
heating and cooling. Avoid frequent temperature
adjustment; turning the unit off and back on before
pressures equalize puts stress on the unit compressor.
Fan Switch
In AUTO or INT (intermittent) mode, the blower operates
only when the thermostat calls for heating or cooling. This
mode is generally preferred when humidity control is a
priority. The ON or CONT mode provides continuous
indoor blower operation, regardless of whether the
compressor or auxiliary heat are operating. This mode is
required when constant air circulation or filtering is desired.
System Switch
Set the system switch for heating, cooling or auto
operation. The auto mode allows the heat pump to
automatically switch from heating mode to cooling mode to
maintain predetermined comfort settings. Many heat
pump thermostats are also equipped with an emergency
heat mode which locks out heat pump operation and
provides temporary heat supplied by the auxiliary heat.
Indicating Light
Most heat pump thermostats have an amber light which
indicates when the heat pump is operating in the
emergency heat mode.
Temperature Indicator
Temperature indicator displays actual room temperature.
PROGRAMMABLE THERMOSTATS
Your Lennox system may be controlled by a
programmable thermostat. These thermostats provide the
added feature of programmable time-of-day setpoints for
both heating and cooling. Refer to the user’s information
manual provided with your thermostat for operation
details.
PRESERVICE CHECK
If your system fails to operate, check the following before
calling for service:
Make sure all electrical disconnect switches are ON.
Make sure the room thermostat temperature selector
AND the system switch are properly set.
Replace any blown fuses, or reset circuit breakers.
Make sure unit access panels are in place.
Make sure air filter is clean.
Locate and record unit model number before calling.
Start−Up and Performance Checklist
Job Name
Job no.
Date
Job Location
City
State
Installer
City
State
Unit Model No.
Serial No.
Service Technician
Nameplate Voltage
Rated Load Ampacity
Compressor
Outdoor Fan
Maximum Fuse or Circuit Breaker
Electrical Connections Tight?
Indoor Filter clean?
Supply Voltage (Unit Off)
Indoor Blower RPM
S.P. Drop Over Indoor (Dry)
Outdoor Coil Entering Air Temp.
Discharge Pressure
Suction Pressure
Refrigerant Charge Checked?
Refrigerant Lines:
Leak Checked?
Properly Insulated?
Outdoor Fan Checked?
Service Valves:
Fully Opened?
Caps Tight?
Thermostat
Voltage With Compressor Operating
Calibrated?
Properly Set?
Level?
