Repair Procedures - Daikin VRV IV+ Service Manual

3 Components
5 Measure the resistance between the pins 1‑2 of the high
pressure switch connector to check if it is open or closed.
6 Compare the result with the trigger and reset conditions of the
high pressure switch (graphic below).
INFORMATION
If the high pressure switch was triggered open, it will stay
open until the refrigerant pressure drops below the reset
pressure of the high pressure switch.
a
d
c
f
a High pressure switch protection control
b Pressure
c High pressure switch closed
d High pressure switch open
e High pressure switch operating pressure
f High pressure switch reset pressure
INFORMATION
See "6.6 Safety devices" on page 183
pressure switch operating and reset pressure values.
INFORMATION
Connect the service checker tool to the unit or use field
settings mode 1‑42 (see
to monitor the high pressure.
If the state of the high pressure switch (open or closed)
matches the state determined through the measured
pressure, but the pressure is NOT correct on the user
interface display, replace the applicable PCB.
High pressure switch
connector measurements are
correct?
Yes
No
To perform an electrical check of the high
pressure switch (detailed procedure)
Prerequisite: Stop the unit operation (via the user interface, central
controller, operation switch, ...).
Prerequisite: Turn OFF the respective circuit breaker.
Prerequisite: Remove the required plate work, see
work" on page 118.
1 Recuperate the refrigerant from the refrigerant circuit, see
"4.2.2 Repair procedures" on
2 Fill the refrigerant circuit with nitrogen until pressurized just
below operating pressure of the high pressure switch.
3 Disconnect the high pressure switch connector from the PCB.
4 Measure the resistance between the pins 1‑2 of the high
pressure switch connector. The switch MUST be closed.
5 Fill the refrigerant circuit with nitrogen until pressurized just
above operating pressure of the high pressure switch.
Service manual
98
https://daikin-p.ru/catalog/vrv-daikn/naruzhnye-vrv-bloki-daikin
e b
for the high
"6.9 Field settings" on page 188)
Then
High pressure switch is OK.
Return to the troubleshooting of
the specific error and continue
with the next procedure.
Replace the high pressure
switch, see "3.7.2 Repair
procedures" on page 98.
"3.13 Plate
page 136.
6 Measure the resistance between the pins 1‑2 of the high
pressure switch connector. The switch MUST be open.
7 Lower the pressure of the nitrogen in the refrigerant circuit just
above reset pressure of the high pressure switch.
8 Measure the resistance between the pins 1‑2 of the high
pressure switch connector. The switch MUST be open.
9 Lower the pressure of the nitrogen in the refrigerant circuit just
below reset pressure of the high pressure switch.
10 Measure the resistance between the pins 1‑2 of the high
pressure switch connector. The switch MUST be closed.
High pressure switch
connector measurements are
correct?
Yes
No
3.7.2

Repair procedures

To remove the high pressure switch
Prerequisite: Stop the unit operation (via the user interface, central
controller, operation switch, ...).
Prerequisite: Turn OFF the respective circuit breaker.
Prerequisite: Remove the required plate work, see
work" on page 118.
Prerequisite: Recuperate the refrigerant from the refrigerant circuit,
see "4.2.2 Repair procedures" on
1 If needed, remove any parts to create more space for the
removal of the high pressure switch.
2 Disconnect the high pressure switch connector from the PCB.
a
c
e
c
d
a High pressure switch
b High pressure switch pipe
c Screw
d Clamp
e Plate
3 Remove the screws, the clamps and the plate.
4 Cut all tie straps that fix the high pressure switch harness.
5 Cut the high pressure switch pipe using a pipe cutter.
6 Remove the high pressure switch from the unit.
7 Supply nitrogen to the refrigerant circuit. The nitrogen pressure
MUST NOT exceed 0.02 MPa.
Then
High pressure switch is OK.
Return to the troubleshooting of
the specific error and continue
with the next procedure.
Replace the high pressure
switch, see "3.7.2 Repair
procedures" on page 98.
"3.13 Plate
page 136.
d
b
RYYQ+RYMQ+RXYQ8~20U7Y1B
VRV IV+ Heat Pump
ESIE18-14 – 2019.07