Page 22
Installer’s Guide
Pre-Start Quick Checklist
Is the unit properly located and level with the proper
clearance? See Figures 1-6, pages 4-9.
Is the duct work correctly sized, run, taped, insulated, and
weatherproofed with proper unit arrangement? See Ductwork
Installation section on page 16.
Is the gas piping correctly sized, run, trapped, and purged of
air? See Gas Piping section on page 17.
Is the condensate line properly sized, run, trapped, and
pitched? See Condensate drain section on page 16.
Is the filter of the correct size and number? Is it clean and in
place? See Air Filter section on page 19.
Is the wiring properly sized and run according to the unit wiring
diagram?
Are all the wiring connections, including those in the unit,
tight?
Has the unit been properly grounded and fused with the
recommended fuse size?
Is the thermostat correctly wired and well located?
Is the W1 to W2 jumper installed at the unit when using a
*CONT802 or *CONT803 Comfort Control?
Have the air conditioning systems been checked at the service
ports for charge and leak tested if necessary?
Does the condenser fan and indoor blower turn free without
rubbing, and are they tight on the shafts?
Has the indoor blower speed been determined and the proper
speed been set?
Has all work been done in accordance with applicable local
and national codes?
Are all covers and access panels in place to prevent air loss
and safety hazards?
Starting the Unit in the Cooling Mode
NOTE:
See the section on “Sequence of Operation”, page
24, for a description of the cooling operating sequence.
To start the unit in the cooling mode, set the comfort control
to COOL and adjust the cooling setpoint below the room
temperature. Wait for the minimum compressor off time to
elapse. The condenser (outdoor) fan motor, compressor, and
evaporator (indoor) fan motor will operate automatically.
Step 5—Unit Startup
Operating Pressures
After the unit has operated in the cooling mode for a short
period of time, install pressure gauges on the gauge ports of
the discharge and suction line valves. Check the suction and
discharge pressures and compare them to the normal operating
pressures provided in the unit’s SERVICE FACTS.
NOTE:
Do not use the PRESSURE CURVES from the unit’s
SERVICE FACTS to determine the unit refrigerant charge.
The correct charge is shown on the unit nameplate. To charge
the system accurately, weigh in the charge according to the
unit nameplate and check subcooling against the Subcooling
Charging Table in the SERIVCE FACTS.
Voltage
With the compressor operating, check the line voltage at the unit. The
voltage should be within the range shown on the unit nameplate. If low
voltage is encountered, check the size and length of the supply line
from the main disconnect to the unit. The line may be undersized for
the length of the run.
Cooling Shut Down
Set the comfort control to OFF or adjust the cooling
setpoint above the room temperature.
Starting the Unit in the Heat Pump Heating Mode
NOTE:
See the section on “Sequence of Operation”,
page 23, for a description of the heat pump heating
operating sequence.
Check to make sure all grilles and registers are open and
all unit access doors are closed before start-up.
The comfort control may be temporarily operated in
Manual Test Mode for the *CONT402 or in Installer
System Test mode for the *CONT802 AND *CONT803.
These are modes designed to be used to “bump” the
system on the various capacity stages. Since the test
mode timeouts are 1 minute and 5 minutes respectively
(in the absence of installer key presses), these modes
are not designed to be used as the only means of system
checkout. Normal thermostat operation should be used
for operating the unit for extended periods of time.
To start the unit in the heat pump heating mode, set the
comfort control to HEAT and adjust the heating setpoint
slightly above the room temperature. Wait for the
minimum compressor off time to elapse. The condenser
(outdoor) fan motor, compressor, and evaporator (indoor)
fan motor will operate automatically.
Heat Pump Heating Shut Down
Set the comfort control to OFF or adjust the heating
setpoint below the room temperature.
Gas Furnace Heating Cycle
In addition to the heat pump controls, these units are
equipped with a solid-state ignition control that lights the
burners each time the thermostat calls for heat. The
burners are extinguished during the OFF cycle.
RELEASED 10/Aug/2020 16:34:00 GMT
