NOTE: Refer to outdoor unit installation instructions for system
start-up instructions and refrigerant charging instructions.
Is unit properly located, level, secure, and serviceable?
Has an auxiliary pan been provided under the unit with
separate drain for units installed above a finished ceiling or in
any installation where condensate overflow could cause
Have all webs been removed from the drain connections that
are being used? Have all drain pan plugs not used been
Has the condensate line been properly sized, run, trapped,
pitched, and tested?
Is the ductwork correctly sized, run, taped, and insulated?
Have all cabinet openings and wiring been sealed?
Is the indoor coil orifice size correct?
Have all unused orifice replacement parts and packaging
been disposed of?
Is the filter clean, in place, and of adequate size?
Is the wiring neat, correct, and in accordance with the wiring
Is the unit properly grounded and protected (fused)?
Is the thermostat correctly wired and in a good location?
Are all access panels in place and secure?
Check Blower Operation
1. Set thermostat to FAN ON.
2. The indoor blower should come on.
Check Electric Heater (if used)
1. Set thermostat to call for auxiliary heat (approximately 5°F
above ambient temperature). The indoor blower and auxiliary
heat should come on together. Allow a minimum of 3 minutes
for all sequencers to cycle on.
2. Set the thermostat so it does not call for heat. Allow up to
5 minutes for all sequencers to cycle off.
Cooling blower speed
For proper cooling operation, the airflow through the indoor
coil should be between 350 and 450 CFM per ton of cooling
capacity (or 350 - 450 CFM per 12,000 Btu/h) based on the
rating of the outdoor unit.
The cooling blower speed is factory configured to provide
correct airflow for an outdoor unit that matches the maximum
cooling capacity rating of the air handler.
If the outdoor unit is smaller than the maximum cooling
capacity rating for the air handler, the cooling blower speed
may need to be changed. Refer to Blower Performance
IMPORTANT: The cooling blower speed must be set to provide a
minimum of 350 CFM airflow per ton (12,000 Btu/h) of outdoor
Disconnect all power supplies before servicing.
Replace all parts and panels before operating.
Failure to do so can result in death or electrical shock.
To change blower speed: Refer to "Wiring Diagram—
Electric Heat and Blower."
1. Disconnect all power supplies.
2. Remove the air handler access panel.
3. Locate pin number 2 on the blower relay. Two black wires are
connected to this terminal pin. One connects to pin number 5
on the blower relay, one connects to an inline splice
connecting to a red or black wire.
4. Remove the wire going to the 4-pin blower motor connector
from the splice.
5. Connect the blower lead (Red [LO], Black [HI]) onto the splice
from the 4-pin blower motor connector.
NOTE: Unused blower speeds are shipped from the factory
covered with a plastic cap. Remove this cap from the new
blower speed terminal and replace it over the factory-set
6. Replace all panels.
7. Reconnect power.
Blower Performance Chart
All factory settings are low-speed.
All data given while air handler is operating with a dry DX coil
and no air filter installed.
Electrical Shock Hazard
CFM @ ESP. - in. W.C.