Verify Orifice Size
NOTE: Some models are equipped with thermo expansion valve
and do not require any orifice change.
A. Thermo expansion valve
IMPORTANT: The proper orifice size is dependent on indoor coil/
outdoor unit combination and application.
1. Consult the outdoor unit literature to determine whether the
indoor unit has the correct orifice installed.
2. If a change of the orifice is required, loosen the brass hex nut
and separate the orifice extension stub from the brass hex
A. Distributor fitting
B. Mounting flange
C. Piston orifice
D. Ring seal (supplied)
3. Remove the orifice with an orifice extractor tool.
4. Insert the proper orifice into the fitting, seal end first. Make
sure the orifice is free to move in the fitting.
5. Replace the brass hex nut.
NOTE: Overtightening the brass hex nut will crush the gasket
and may result in a system leak or stuck piston.
6. Dispose of all packaging and unused parts.
E. Orifice extension stub
F. 0.812" brass hex nut
G. Brass hex fitting
Connect Refrigerant Lines
Refrigerant lines must be connected by a licensed, EPA certified
refrigerant technician in accordance with established procedures.
Connecting refrigerant lines must be clean, dehydrated,
refrigerant-grade copper lines. Air handler coils should be
installed only with specified line sizes for approved system
Handle the refrigerant lines gently during the installation
process. Sharp bends or possible kinking in the lines will
cause a restriction.
Do not remove the caps from the lines or system connection
points until connections are ready to be completed.
1. Route the suction and liquid lines from the fittings on the
indoor coil to the fittings on the outdoor unit. Run the lines in
as direct a path as possible avoiding unnecessary turns and
2. Make sure that the suction line is insulated over the entire
exposed length and that both suction and liquid lines are not
in direct contact with floors, walls, ductwork, floor joists, or
3. Connect the suction and liquid lines to the evaporator coil.
4. To avoid damaging the rubber grommets in the cabinet while
brazing, slide the rubber grommets over the refrigerant lines
until they are away from the heat source.
5. Braze with an alloy of silver or copper and phosphorus with a
melting point above 1,100°F.
NOTE: Do not use soft solder.
6. Reinstall the rubber grommets after brazing is finished.
7. Make sure outdoor condenser/heat pump has been put in
place according to the Installation Instructions and is
connected to the refrigerant lines.
Make Electrical Connections—Models Without
Factory-Installed Electric Heat
Disconnect all power supplies before servicing.
Replace all parts and panels before operating.
Failure to do so can result in death or electrical shock.
1. Disconnect all power supplies.
2. Remove the blower access panel.
3. Route the field supply wires to the air handler electrical
Electrical Shock Hazard