Hitachi UTOPIA RAS-4HVRP2E - Removing the High Pressure Switch and Pressure Switch for Control

9 Servicing
RAS-(4-6)H(V)(R/N)(C/P)2E
SMGB0136 rev.0 - 07/2021
193
9
9.3.8 Removing the High pressure switch and Pressure switch for control
1 Disassembly the service cover according to the item “9.3.1Removingservicecover”.
2 Disassembly the bottom service cover and rear cover according to the item “9.3.4Removingbottomservicecover
andrearcover”.
3 Collect the refrigerant according to the item “3.4Refrigerantcharge”.
- If the outdoor unit is installed close to a wall remove the refrigerant piping and move the unit from the wall.
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High Pressure Switch
a. Disconnect the Faston terminals -1-.
b. Move all cables and remove the necessary components to leave the working area free.
c. Protect the 4-way -5- valve with a wet cloth.
d. Protect the check valve with a wet cloth.
e. Protect the Pressure Sensor -6- for Discharge Pipe -4- with a wet cloth.
f. Heat the brazing joint -3- between the High Pressure Switch -2- and the Discharge Pipe -4- until the switch is
released.
g. Remove the High Pressure Switch -2- and install the new one.
h. Protect the new High Pressure Switch -2- with a wet cloth.
i. Braze the connection -3- to the Discharge Pipe -4- until the switch is properly installed.
4
3
2
1
5
6
j. Allow the brazing to cool down for a few minutes.
k. Remove all used protections and wet cloths.
l. Move the cables until they are the same as they were originally.
m. Connect the Faston terminals to the switch.
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Pressure sensor for Discharge Pipe
a. Disconnect the Pressure Sensor CN100 conntector in PCB1 according to the item “9.3.6Removingelectrical
box”.
b. Move all cables and remove the necessary components to leave the working area free.
c. Protect the 4-way -3- valve with a wet cloth.
d. Protect the check valve with a wet cloth.
e. Protect the High Pressure Switch -1- with a wet cloth.
f. Heat the brazing joint between -4- the Pressure sensor -5- and the discharge pipe -2- until the sensor is released.
g. Remove the sensor -5- with his wire and install the new one.
h. Protect the new sensor with a wet cloth.