Refrigerant Piping Connections - Lennox VRF V33B Series Installation Instruction

Refrigerant Piping Connections

WARNING
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
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).
6. Align the threaded connections with the flared
refrigerant lines. Tighten the flare nuts lightly at first to
obtain a smooth match (Figure 3-B).
7. Once snug, continue another half-turn on each nut
which should create a leak-free joint. A torque wrench
may be used to tighten flare nuts using Table 2
recommendations. See Figure 4. Do not over-tighten
a flared joint. Flared connections should always
be accessible and must be insulated to prevent
condensation.
connections have been
8. After refrigerant piping has been installed and
checked for leaks, apply insulation over all flared joints
ensuring an air tight seal has been made between unit
connections and field supplied insulated piping. All
field piping connections shall be insulated and air tight
to prevent unwanted condensation build-up. Figure 5.
IMPORTANT!
The compressor
oil (Polyvinylether).
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.
Table 1. Refrigerant Piping Connections
Nominal
Capacity
(Btuh)
9000
12000
15000
18000
24000
30000
36000
48000
A
B
Figure 3. Making Connections
(Male to Female Connection)
7
in this unit contains
PVE oil is formulated
Liquid Line Vapor Line
in. in.
1/4 1/2
3/8 5/8
APPLY REFRIGERANT LUBRICANT
ON THE OUTSIDE OF THE FLARE
MALE FLARE
CONNECTION
PVE
for