11 Troubleshooting
Installer and user reference guide
37
RXYSCQ4~6TMV1B
VRV IV-S system air conditioner
4P404224-1C – 2019.07
10.4
About service mode operation
Refrigerant recovery operation/vacuuming operation is possible by
applying setting [2‑21]. Refer to
"7.2 Making field settings" on
for details how to set mode 2.
When vacuuming/recovery mode is used, check very carefully what
should be vacuumed/recovered before starting. See installation
manual of the indoor unit for more information about vacuuming and
recovery.
10.4.1
To use vacuum mode
1
When the unit is at standstill, activate setting [2‑21] to start
vacuuming mode.
Result:
When confirmed, the indoor and outdoor unit expansion
valves will fully open. At that moment H1P lights and the user
interface of all indoor units indicate TEST (test operation) and
(external control) and the operation will be prohibited.
2
Evacuate the system with a vacuum pump.
3
Press BS1 to stop vacuuming mode.
10.4.2
To recover refrigerant
This should be done by a refrigerant reclaimer. Follow the same
procedure as for vacuuming method.
DANGER: RISK OF EXPLOSION
Pump down – Refrigerant leakage.
If you want to pump
down the system, and there is a leak in the refrigerant
circuit:
▪ Do NOT use the unit's automatic pump down function,
with which you can collect all refrigerant from the
system into the outdoor unit.
Possible consequence:
Self-combustion and explosion of the compressor
because of air going into the operating compressor.
▪ Use a separate recovery system so that the unit's
compressor does NOT have to operate.
NOTICE
Make sure to NOT recover any oil while recovering
refrigerant.
Example:
By using an oil separator.
11
Troubleshooting
11.1
Overview: Troubleshooting
Before troubleshooting
Carry out a thorough visual inspection of the unit and look for
obvious defects such as loose connections or defective wiring.
11.2
Precautions when troubleshooting
WARNING
▪ When carrying out an inspection on the switch box of
the unit, ALWAYS make sure that the unit is
disconnected from the mains. Turn off the respective
circuit breaker.
▪ When a safety device was activated, stop the unit and
find out why the safety device was activated before
resetting it. NEVER shunt safety devices or change
their values to a value other than the factory default
setting. If you are unable to find the cause of the
problem, call your dealer.
DANGER: RISK OF ELECTROCUTION
WARNING
Prevent hazards due to inadvertent resetting of the thermal
cut-out: power to this appliance MUST NOT be supplied
through an external switching device, such as a timer, or
connected to a circuit that is regularly turned ON and OFF
by the utility.
DANGER: RISK OF BURNING
11.3
Solving problems based on error
codes
In case of a displayed malfunction code, perform correcting actions
as explained in the malfunction code table.
After correcting the abnormality, press BS3 to reset the malfunction
code and retry operation.
INFORMATION
If a malfunction occurs, the error code is displayed on the
user interface of the indoor unit.
INFORMATION
If a malfunction occurs, the error code is displayed on the
outdoor unit's 7‑segments display and on the user interface
of the indoor unit.
11.3.1
Error codes: Overview
Main code
Cause
Solution
▪ The stop valve of an outdoor unit is left closed.
▪ Refrigerant overcharge
▪ Open the stop valve on both the gas and liquid side.
▪ Recalculate the required amount of refrigerant from the
piping length and correct the refrigerant charge level by
recovering any excessive refrigerant with a refrigerant
recovery machine.
▪ The stop valve of an outdoor unit is left closed.
▪ Insufficient refrigerant
▪ Open the stop valve on both the gas and liquid side.
▪ Check if the additional refrigerant charge has been
finished correctly. Recalculate the required amount of
refrigerant from the piping length and add an adequate
amount of refrigerant.
