17
AIR BALANCING
A variable pulley is fitted to the motor shaft in order to adjust the blower performance to the pressure drop at the duct
work. The pulley must be adjusted when the measured external static pressure and air volume (motor current draw)
differ from the nominal values at the unit. As a default setting, the variable diameter pulley is open by 2 turns.
CASE N°1:
The measured air flow is higher than the nominal air flow. You must reduce the fan rotation speed by opening the
variable diameter pulley. It is imperative to adjust the pulley, otherwise the motor’s internal protection will trigger
because of overheating taking the entire unit out of operation.
CASE N°2:
The measured air flow is lower than the nominal air flow. You must increase the fan rotation speed by closing the
variable diameter pulley.
OpERATING CHECK LIST
GENERAL
Cheek for any unusual noises or vibration in the running components, particularly at the main blower.
pHASE ROTATION pROTECTION
If the phase at the power supply are not correct, the phase rotation protection device will prevent the machine
from starting.
ELECTRICAL
OpERATING vOLTAGE:
Recheck voltage at unit supply terminals.
CONTROL
1. Operate system and thermostat switches.
2. Check unit is wired for correct control of blower, cooling and heating modes.
3. Verify all sensor signal, using the controller display.
COMpRESSOR AND REFRIGERATION SYSTEM
1. If outdoor air temperature is below 0°C make sure that the compressor crankcase heater has been
on for at least one hour before starting compressor.
2. Running check: Start the compressor. Check for any unusual noise or vibration.
3. Operating pressures: Operate the unit for at last 20 minutes and ensure that the refrigerant pressures
are stabilised, and cheek that they are within the normal operating ranges.
4. Operating Temperature: Check discharge, suction and liquid temperatures.
5. Compressor output temperature in cooling mode should not normally exceed 105° C.
6. Compressor intake air superheating must be between 5° K and 12° K.
This section applies to all
HAN
from model 15.
Summary of Contents for HAN 10
Page 2: ......
Page 23: ...APPENDIX ANNEXE ANLAGE ALLEGATO ANEXO APPENDIX ANNEXE ANLAGE ALLEGATO ANEXO ...
Page 30: ...APPENDIX ANNEXE ANLAGE ALLEGATO ANEXO VIII han 10 13 T1PRI T1SEC ...
Page 31: ...APPENDIX ANNEXE ANLAGE ALLEGATO ANEXO IX han 15 17 19 T1PRI T1SEC ...
Page 32: ...APPENDIX ANNEXE ANLAGE ALLEGATO ANEXO X han 25 31 T1PRI T1SEC ...
