Daikin VRV IV+, Service Manual

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2 | Troubleshooting
Service manual
66
REYQ8~20+REMQ5U7Y1B
VRV IV+ Heat Recovery
ESIE18-15B – 2020.05
Possible cause: Faulty or clogged air filter.
9 Adjust external static pressure setting for ducted type indoor units, if
necessary.
10 Perform a check of the indoor unit fan motor. See service manual of the
respective indoor unit(s).
Possible cause: Faulty indoor unit fan motor.
11 Perform a check of the indoor air thermistor. See indoor unit manuals to
check thermistors on indoor units.
Possible cause: Faulty indoor air thermistor.
12 Check all indoor units operation in heating mode. Check for room
temperatures below 20°C. Check if caution disappears once rooms heat‑up. If
NOT, continue checking the cause of the wet operation.
Possible cause: Indoor room temperature too low when in heating mode. Too
cold rooms might create more subcool resulting in wet operation.
INFORMATION
If all procedures listed above have been performed and the problem is still present,
contact the helpdesk.
2.3.42 F4-14 – Indoor unit wet operation alarm
Trigger Effect Reset
In cooling mode on indoor
Unit: ((T
Gas Pipe
– (T
Liquid Pipe
) <
2,5 °C while Indoor
Expansion Valve opening
< 300 pulse AND Outdoor
Unit Discharge Superheat
= (T
Discharge
- T
condensation
) <
10 °C for more than 45
minutes
Unit stops Operating. Manual reset via user
interface.
To solve the error code
INFORMATION
It is recommended to perform the checks in the listed order.
1 Clean the air filters of the indoor unit(s). See service manual of the respective
indoor unit(s).
Possible cause: Faulty or clogged air filter.
2 Use Service Checker to find the indoor units where difference between gas
pipe thermistor and liquid pipe thermistor meets the trigger condition and
indoor unit expansion valve opening is lower than 300 pulses.
3 Stop these indoor units while some other indoor units are still in operation
and system is in Cooling Operation. Check if the liquid pipe temperature read-
out is close to evaporation temperature. Or use an expansion valve
stethoscope to determine the refrigerant flow on expansion valve while
expansion valve is closed.