Haier MRV SII AU042FNEUA Service Manual page 31

If the coating on the fastening area is stripped off, the nuts rust easily.
Dimensions (bottom view) (unit of measurement: mm)
175
84
259
(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.
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.
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 operation instruction.
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
D
E
175
80
F
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)
70
29
Spanner
Connector
Nut
Spanner