GB - 15
E N G L I S H
Installation instructions supplement
Head pressure controller and HIP remote
manual reset
Configuration
The head pressure control “HPC” is made of three parts:
• Dual speed fan motor.
• Interface relay.
• Pressure sensor, complete with 500 mm wiring.
The high pressure switch “HIP” has been selected at automatic reset.
If “HIP” trips, cycle the power supply OFF and ON to reset the system,
because the electrical box is equipped with relays that prevent the
unit from starting, until the indoor control is switched OFF.
When head pressure drops below 3000 kPa (30 bar; 420 psig) it is
possible to restart the unit switching the indoor control ON.
Operations mode
High speed:
If the condensing pressure is above the high pressure limit, the fan
operates at high speed.
Low speed:
If the condensing pressure is below the low pressure limit, the fan
operates at low speed.
Hard start:
At each compressor starting the fan motor high speed is reached by
the pressure sensor operation.
Head pressure controller: wiring diagram
Pressure setting
High speed pressure set at 2323 kPa (23.2 bar; 337 psig).
Low speed pressure set at 1896 kPa (18.9 bar; 275 psig).
Troubleshooting
See paragraph “Troubleshooting”.
Note:
At start-up or in case of re-start after a pause of several hours
at – 10
°
C, with low voltage supply (198V) high pressure switch
HIP may trip off the unit. In this case, the remote reset by indoor
control (infrared) can be done for unit restarting.
FM
FC
Live power supply
Neutral power supply
Pressure sensor
Interface relay
Dual speed fan motor
FM = Fan motor
FC = Fan capacitor
38GLS...G