Emerson Liebert CRV User Manual page 30

S soft copper: by hand or bending device.
S hard copper: use preformed curves. Do not overheat the pipes when brazing so as to
minimize oxidation.
2) Connect the pipes to the condenser:
S Condensers with butt-brazed pipe connections: cut the pipe, enlarge it and braze it to the
pipeline.
S Condensers with threaded tap connections: flange the pipes and connect.
RESPECT THE DIRECTION OF REFRIGERANT FLOW (SEE LABELS ON RE-
FRIGERANT CONNECTIONS).
3) Wash out the pipelines as follows:
a) Plug up the free ends of the pipes.
b) Connect a helium or nitrogen cylinder, fitted with a reducer (max. pressure 10 bar), to
the ¼" SAE Schrader cock of the condenser.
c) Pressurize the pipes with helium or nitrogen.
d) Unplug the pipes instantaneously.
e) Repeat a) - d) several times.
THIS OPERATION IS ESPECIALLY IMPORTANT WHEN HARD COPPER PIPING IS
USED.
4) Open all the room unit shut-off valve.
5) Discharge the room unit pressurized with helium (at 1 bar) opening the charge cocks so that
all the branches of the circuit are discharged (e.g. on the receiver, on the low pressure side and
on the compressor delivery).
6) De-braze the bottoms from the connections of the room unit.
7) Fix (braze) the pipes to the connections on the air conditioner.
8) Connect the refrigerant safety valve to the outdoor with a copper pipe sized in order to satisfy
the requirements of EN13163 (i.e. till 4m length, Øi 20mm)
Tab. d -
Equivalent lengths (meters - feets) of: curves, shut-off and check valves
Nominal
diameter
90°
12 mm 0.50 m
14 mm 0.53 m
16 mm 0.55 m
18 mm 0.60 m
22 mm 0.70 m
45° 180°
0.25 m 0.75 m
0.26 m 0.80 m
0.27 m 0.85 m
0.30 m 0.95 m
0.35 m 1.10 m
22
Refrigeration Connections
90°
2.10 m 1.90 m
2.20 m 2.00 m
2.40 m 2.10 m
2.70 m 2.40 m
3.20 m 2.80 m