9 Maintenance and service
Installer and user reference guide
42
RWEYQ8~1 RWEYQ8~14T9Y1B
VRV IV water-cooled system air conditioner
4P452191-1 – 2017.04
Step
Description
Pipe length check
Refrigerant amount check
Pump down operation
Unit stop
Note:
During the test operation, it is not possible to stop the unit
operation from a user interface. To abort the operation, press BS3.
The unit will stop after ±30 seconds.
5
Check the test operation results on the outdoor unit 7‑segment
display.
Completion
Description
Normal completion No indication on the 7‑segment display (idle).
Abnormal
completion
Indication of malfunction code on the
7‑segment display.
Refer to
"8.6 Correcting after abnormal
completion of the test run" on page 42
to take
actions for correcting the abnormality. When
the test operation is fully completed, normal
operation will be possible after 5 minutes.
8.6
Correcting after abnormal
completion of the test run
The test operation is only completed if there is no malfunction code
displayed on the user interface or outdoor unit 7‑segment display. In
case of a displayed malfunction code, perform correcting actions as
explained in the malfunction code table. Carry out the test operation
again and confirm that the abnormality is properly corrected.
INFORMATION
Refer to the installation manual of the indoor unit for
detailed malfunction codes related to indoor units.
8.7
Operating the unit
Once the unit is installed and test operation of outdoor unit and
indoor units is finished, the operation of the system can start.
For operating the indoor unit, the user interface of the indoor unit
should be switched ON. Refer to the indoor unit operation manual for
more details.
9
Maintenance and service
NOTICE
Maintenance must be done by an authorised installer or
service agent.
We recommend to do maintenance at least once a year.
However, applicable legislation might require shorter
maintenance intervals.
NOTICE
In Europe, the
greenhouse gas emissions
of the total
refrigerant charge in the system (expressed as tonnes
CO
2
-equivalent) is used to determine the maintenance
intervals. Follow the applicable legislation.
Formula to calculate the greenhouse gas emissions:
GWP value of the refrigerant × Total refrigerant charge [in
kg] / 1000
9.1
Overview: Maintenance and
service
This chapter contains information about:
▪ Preventing electrical hazards when maintaining and servicing the
system
▪ Cleaning the plate heat exchanger
▪ The refrigerant recovery operation
9.2
Maintenance safety precautions
DANGER: RISK OF ELECTROCUTION
DANGER: RISK OF BURNING
NOTICE: Risk of electrostatic discharge
Before performing any maintenance or service work, touch
a metal part of the unit in order to eliminate static electricity
and to protect the PCB.
9.2.1
To prevent electrical hazards
When performing service to inverter equipment:
1
Do not open the electrical component box cover for 10 minutes
after the power supply is turned off.
2
Measure the voltage between terminals on the terminal block
for power supply with a tester and confirm that the power supply
is shut off. In addition, measure points as shown in the figure
below, with a tester and confirm that the voltage of the capacitor
in the main circuit is less than 50 V DC.
3
To prevent damaging the PCB, touch a non-coated metal part
to eliminate static electricity before pulling out or plugging in
connectors.
9.3
Maintenance of the plate heat
exchanger
The performance of a plate heat exchanger may decline due to scale
accumulation. It may be damaged by freezing due to the decrease in
the flow rate. For this reason, it is necessary to carry out
programmed maintenance at regular intervals in order to prevent
scale.
At the beginning of the season, carry out following inspections:
▪ water quality test and follow the recommendations as described in
"5.4.1 Water quality requirements" on page 19
▪ clean the water filter,
▪ water flow rate is correct,
▪ operational conditions (e.g. pressure, water flow rate, outlet
temperature,…) are normal.
9.3.1
To clean the plate heat exchanger
Disassembling and cleaning of the plate heat exchanger is not
possible. Please use following steps.
Prerequisite:
Provide a connection port on the water inlet and on
the water outlet and connect a circulation pump in between these 2
connection ports when cleaning with chemicals.
Prerequisite:
Provide a stop valve in front of the inlet water pipe
connection port and a stop valve after the outlet water connection
port.
Prerequisite:
Use a solution with 5% diluted formic, citric, oxalic,
acetic or phosphoric acid for cleaning scale. NEVER use
hydrochloric, sulphuric or nitric acid because such solutions have a
strong corrosive feature.
