Daikin VRV IV+ Service Manual page 209

To perform a position check of the 4-way valve
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05
Y4S valve:
▪ Cooling mode*
▪ Oil Return operation in Cooling
▪ Defrost/Oil return operation in Heating
▪ Oil Return operation in Simultaneous Cooling/Heating
* Y4S may also be ON if low load condition
Y5S valve:
▪ Cooling mode
▪ Low load Heating mode
▪ Simultaneous Cooling/Heating operation
▪ Defrost/Oil return operation in Heating
▪ Oil Return operation in Simultaneous Cooling/Heating
14 With the 4‑way valve connector connected to the PCB, measure the voltage
on the 4‑way valve connection of the PCB.
Result: The measured voltage MUST be 0 V AC.
Is the measured voltage correct?
Yes
No
1 First perform an electrical check of the 4‑way valve, see
4
procedures" [ 206].
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.
2 Activate Heating operation via the Cool/Heat master user interface.
CAUTION
It is NOT possible to activate operation modes with another user interface than the
Cool/Heat master user interface.
INFORMATION
It is recommended to connect the service monitoring tool to the unit and verify the
operation mode of the 4-way valve.
3 Check with a contact thermometer (or by touching) if the flow through the 4-
way valve corresponds with the flow shown in the flow diagram. (See
"6.3 Piping diagram" [
Is the flow correct?
Yes
No
Action
Perform a position check of the 4-way
valve, see
procedures" [
Perform a check the main PCB, see
"3.11 Main
4
401]).
Action
Skip the next step of this procedure.
Perform the next step of this procedure.
3 Components
|
"3.1.1 Checking
4
206].
4
PCB" [ 290].
"3.1.1 Checking
Service manual
209