6
Refrigerant Piping Connections
Refrigerant leaks are unlikely; however, if a refrigerant
leak occurs, open a door or windows to dilute the
refrigerant in the room. Turn off the unit and all other
appliances that may cause a spark. Call a licensed
professional HVAC technician (or equivalent) to repair
the leak.
Use only R410A refrigerant to charge this system. Use
of other refrigerant or gas will damage the equipment.
Do not allow air or other contaminants to enter system
during installation of refrigerant piping. Contaminants
will result in lower system capacity and abnormally high
operating pressures and may result in system failure or
explosion.
Insulate all refrigerant piping.
Refrigerant pipes may be very hot during unit operation.
Do not allow contact between wiring and bare copper
pipes.
After refrigerant piping connections have been
completed, check the system for leaks per commissioning
instructions.
Field piping consists of two copper lines connected to the
indoor unit. Table 1 lists the connection sizes at the indoor
unit. The connections are made using the provided brass
flare nuts at the end of the refrigerant piping connections.
Both lines must be individually insulated.
1. The seal on the unit refrigerant piping connections
should remain in place until the last possible moment.
This will prevent dust or water from getting into the
refrigerant piping before it is connected.
2.
Slowly loosen one of the flare nuts to release the
factory nitrogen charge.
3.
Remove the flare nuts from the connections on the
unit and discard the seal from each of the piping
connections.
4.
Slide the flare nuts onto the ends of the field-provided
refrigerant piping
before
using a suitable flaring tool
to flare the end of the copper pipe.
5.
Apply recommended HFC-410A refrigerant lubricant
to the outside of the flared refrigerant lines (Figure
3-A).
Size
(Btuh)
Liquid Line
in.
Vapor Line
in.
7000
12000
15000
1/4
1/2
18000
24000
30000
36000
48000
3/8
5/8
Table 1. Refrigerant Piping Connections
A
B
CANT ON THE OUTSIDE OF
THE FLARE
MALE FLARE
CONNECTION
Figure 3. Making Connections
(Male to Female Connection)
IMPORTANT
The compressor in this unit contains PVE
oil (Polyvinylether). PVE oil is formulated for
hydrofluorocarbon (HFC) refrigerants, such as R-410a,
which this system contains. While it may have some
miscibility properties with mineral-based oil and POE oil
(Polyolester), it is not recommended to mix PVE oil with
any other type of refrigerant oil.
7. If the unit is being installed in an application that includes
a sheet rock (plasterboard) ceiling, it is required that
an access panel be installed in a suitable location.
This will also allow access for future maintenance
(requirement of Lennox warranty program).
Access is required during the commissioning process
to test the condensate disposal system (See Figure
9), to check the electronic expansion valve and
associated flare nuts (See Figure 3), and to check the
local disconnect.
WARNING
