Daikin VRV IV+ Service Manual page 207

REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05
Is the measured value correct?
Yes
No
When outdoor temperature is mild and unit can switch between heating and
cooling
INFORMATION
This procedure is ONLY possible when the outdoor temperature is within the
temperature range for both Heating and Cooling operation mode. See the
databook on Business Portal for the temperature range of the operation modes.
3 Connect the 4‑way valve connector to the appropriate PCB.
4 Turn ON the power using the respective circuit breaker.
5 Activate Heating operation via the Cool/Heat master user interface.
CAUTION
Activate all units to make sure the system is operating with full Heating load so the
upper heat exchanger 4‑way valve Y5S is switched ON. Check with the service
monitoring tool that Operation Mode is Heating.
6 With the 4‑way valve connector connected to the PCB, measure the voltage
on the 4‑way valve connection of the PCB. The measured voltage MUST be:
▪ 0 V AC for high pressure / low pressure 4‑way valve Y3S
▪ 230 V AC for lower heat exchanger 4‑way valve Y4S
▪ 230 V AC for upper heat exchanger 4‑way valve Y5S. When operating with
low load, Y5S can switch OFF (=0 V AC).
7 De-activate Heating and activate Cooling operation via the Cool/Heat
master user interface.
CAUTION
Activate all units to make sure the system is operating with full Cooling load so the
lower heat exchanger 4‑way valve Y4S is switched ON. Check with the service
monitoring tool that Operation Mode is Cooling.
8 With the 4‑way valve connector connected to the PCB, measure the voltage
on the 4‑way valve connection of the PCB. The measured voltage MUST be:
▪ 230 V AC for high pressure / low pressure 4‑way valve Y3S
▪ 0 V AC for lower heat exchanger 4‑way valve Y4S. When operating with low
load, Y4S can switch ON (=230 V AC).
▪ 0 V AC for upper heat exchanger 4‑way valve Y5S.
Are the measured voltages correct?
Yes
No
3
Action
Continue with the next step.
Replace the 4‑way valve coil, see
"3.1.2 Repair procedures" [
Action
Perform a position check of the 4-way
valve, see "3.1.1 Checking
4
procedures" [ 206].
Perform a check the main PCB, see
4
"3.11 Main PCB" [ 290].
Components
|
4
211].
Service manual
207