Hitachi RWM-(H)FSN3E, Руководство по обслуживанию

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11 Servicing
SMGB0070 rev. 1 - 08/2011
322
7 Install new one by performing the procedures above in
reverse way.
N O T E
• Be careful do not lose the gasket of the expansion
vessel.
• Check the gasket (2), if it is defective, replace by a
new one.
Expansion vessel connection
Gasket (2)
11.2.4 Replacing refrigerant parts
D A N G E R
• Disconnect the Yutaki S from the power supply before touching any of the parts. Do not touch the electrical
box before disconnecting it in order to avoid an electrical shock.
• Wait minimum 10 minutes or more from all power supplies have been turned OFF.
N O T E
• In case of replacing Refrigerant parts, in some cases drain water from the unit it is needed. Close the shutdown
valves and open the drain valves.
• In case of replacing refrigerant parts, collect refrigerant to the outdoor unit by pump down procedure.
• All refrigerant parts are connected by brazing. Check to ensure whether there are flammable things around or
not when using a burner for pipe connections, if not, oil existing pipe inside may ignite.
• Do not expose the refrigerant cycle to the atmosphere for a long period in order to avoid mixing the water and
foreign particles into the refrigerant cycle. After removing refrigerant parts, replace it quickly. If exposed for a
long period, seal the liquid pipe and gas pipe.

Replace expansion valve
1 Remove service cover.
2 Remove the CN26 connector on the expansion valve
control.
3 The butyl sheet is adhered around the piping of the heat
exchanger, the electronic expansion valve and the inlet
piping and outlet piping of the electronic expansion val-
ve. Remove the butyl sheet of the surface of the piping,
the coil part of the expansion valve and the part of the
valve body.
In case of replacing mixing valve motor (drive part):
4 Prepare two spanners. Hold the part of the valve body
with one spanner and loosen the lock nut with another
spanner by turning the lock nut counterclockwise.
5 Turn the lock nut by a few turns. Then, the drive part
separates from the screw and can be removed.
6 Prepare the new drive part for replacement (servicing
part) with the position of the driver (drive screw) already
adjusted.
N O T E
During replacement work, pay attention to the sepa -
ration part and prevent the dust, foreign particle, etc.
from entering into the separation part. (The sensitive
part of the valve is its mechanical system.)Do not da -
mage the junction part of the valve with the tools.