Airwell VVFA Series Service Manual page 24

If the coating on the fastening area is stripped off, the nuts rust easily.
Dimensions (bottom view) (unit of measurement: mm)
174
84
(5) Refrigerant pipe connection
Pipe connection method:
• To ensure the efficiency, the pipe should be as short as possible.
• Daub the refrigerant oil on the connector and the flare nut.
• When bending the pipe, the bending semi-diameter should be as large
as possible against the pipe being broken or bent.
• When connecting the pipe, aim at the center to thread the nut by hand
and tighten it with the double spanners.
• Don't let the impurity such as sand, water etc into the pipe.
Cautions in piping installation:
• When welding the connector with hard solder, charge nitrogen into the pipe against oxidation. Or the oxygen film
in the pipe will clog the capillary and the expansion valve, even caue the deathy accident.
• The refrigerant pipe should be clean. If the water and the other impurity enter the pipe, charge the nitrogen to
clean the pipe. The nitrogen should flow under the pressure of about 0.5Mpa and when charging the nitrogen,
stop up the end of the pipe by hand to enhance the pressure in the pipe, then loose the hand (meanwhile stop up
the other end).
• The piping installation should be executed after the stop valves are closed.
• Before welding the valve and the pipes, use the wet cloth to cool down the valve and the pipes.
• When the connection pipe and the branch pipe need to be cut down, please use the special shears and cannot
use the saw.
Pipe material and specs selection
1.Please select the refrigerant pipe of the below material.
Material: the phosphoric oxidize seamless copper pipe, model: C1220T-1/2H
(diameter is over 19.05); C1220T-0 (diameter is below 15.88).
2.Thickness and specs:
Confirm the pipe thickness and specs according to the pipe selection
method(the unit is with R410A, if the pipe over 19.05 is 0-type, the pressure
preservation will be bad, thus it must be 1/2H type and over the min.
thickness.
3.The branch pipe must be from Haier.
4.When installing the stop valve, refer to the relative operationinstruction.
5.The pipe installation should be in the allowable range.
6.The installation of branch pipe and gather pipe should be performed
according to the relative manual.
A 600
C
439
259
D
174
80
F
E
70
When fastening and loosing the nut,
operate with double spanners, because
only one spanner cannot execute firmly.
If threading the nut as not aiming at
the center, the screw thread will be
damaged, further it will cause leakage.
22
A leg pitch1
B leg pitch2
C Front grill (air outlet
side)
D Drain hole
E Bottom frame
F Knock-out hole (for
piping line)
Spanner
Connector
Nut
Spanner
Drain pipe disposal
• Make sure the drain works
properly.
• In regions where buildups of
snow can be expected, the
accumulation and freezing of
snow in the space between the
heat exchanger and external plate
may lower operating efficiency.
• After punching the knock-out
hole, the application of repair-type
paint on the surface around the
edge sections is recommended to
prevent rust.