9.3 - GMC Board alarm codes (Fig. 16)
There is an LED on the GMC board that displays any board
errors.
The error code can be identified from the flashing LED using
the following table. In the case of more than one error, the
error with the highest priority will be displayed until it is
resolved.
In the case of normal operation, the LED flashes at a
frequency of ½ Hz. In the case of an error, the LED remains of
for 4 seconds, then at a frequency of 1Hz, it flashes a number
of times equal to the error code and then remains off again
for 6 seconds. If the error code has 2 digits, the flashing is
interrupted for 2 seconds between the
first and second digits.
Example: Error 23: LED of for 4 seconds. 2 flashes at a
frequency of 1Hz. Off for 2 seconds. 3 flashes at a frequency
of 1Hz. Off for 6 seconds. The cycle repeats until the LED
turns off because the problem is resolved or if an error with
higher priority occurs.
Fault Code
Description
2
Safety Input
3
Frozen plates exchanger
4
Actual Refrigerant Temperature Sensor (TR)
5
Outdoor Air Sensor of GMC
6
Loss communication to NUI control
7
NUI control Room Sensor
9
Flow Switch error / Water Pump
10
EEProm Corrupt
11
User interface setting mismatch
12
4 Way valve error
13
Loss Communication to RS485 (system coniguration type 6)
14
Loss of Signal From inverter board or High Temperature Release
15
Exit water Temperature Sensor (LWT)
16
Alarm Test
17
Inverter Air Sensor (TO)
18
G-Tr inverter short circuit protection
20
Compressor position Detection Circuit error
21
Inverter Current Sensor error
22
Heat Exchanger Sensors (TE) / (TS)
23
Discharge Temperature Sensor (TD)
24
Outdoor Fan motor error
26
Other unit error
27
Compressor Lock
28
Discharge Temperature error
29
Compressor Breakdown
30
Low pressure system error
31
High pressure system error
Frozen plates exchanger
If this fault code is displayed, it means that the plates
exchanger froze during cooling operation.
The only way to restart the unit is to powered OFF -->ON the
unit.
Before doing this operation, contact the qualified service.
The full installation configuration must be checked (unit and
water loop).
26
RG66012647
10 - UNIT PROTECTION DEVICES
* 6 acceleration/h logic has the priority
IMPORTANT: During functioning in heat pump heating
mode, the unit performs defrost cycles to eliminate any ice
that might form at low temperatures inside the outdoor
unit.
11 - MAINTENANCE
Cleaning the coil
If necessary, proceed as follows for more careful cleaning
of the coil:
Switch the mains supply OFF.
Remove unit top cover by loosening the fixing screws and
lifting the cover. Carefully clean the coil with a vacuum
cleaner from inside to outside. With the same vacuum
cleaner, remove the dust from inside the fan compartment
and the fan blades. Avoid any damage to the blades which
may cause future vibrations and noise.
Replace the unit cover and tighten the screws.
IMPORTANT: The operation must be performed by qualified
personnel.
11.1 - Refrigerant charge check
This check becomes necessary after any refrigerant leak or
after replacement of the compressor.
The best method to correctly charge refrigerant is to
completely empty the refrigerant circuit using refrigerant
recovery equipment.
Then charge the exact quantity of refrigerant according to
the data shown on the unit nameplate. R-410A systems must
be charged with liquid refrigerant. Use the special recharging
equipment (normally in the market) to handle the refrigerant
correctly. The oil used for the compressor is ESTER OIL VG74
(VG68 for size 12kW).
Do not use refrigerants and lubricant besides those
specified. Do not compress air (there must be no air intake
due to leakage in the refrigeration cycles).
All copying, even partial, of this manual is strictly forbidden
Type of safety device
Switch on pressure
Pressure switch on water
300kPa
Anti-Freeze Protection
Adjustable from 3 to 9 °C
Delayed compressor start
180 s max*
OFF-->ON
Delayed compressor stop
180 s*
ON-->OFF
Start Acceleration Limit
6 accelerations/h*
compressor
Release
N.A.
software controlled