Unit installation

30RA/30RH
GB - 10
Refrigerant charge and electronic control
Undercharge
If there is not enough refrigerant in the system, this is indicated by
gas bubbles in the moisture sight glass.
There are two possibilities:
• Small undercharge (bubbles in the sight glass, no signicant
change in suction pressure).
- After detection and repair the unit can be recharged.
- The replenishment of the charge must always be done in the
cooling mode, slowly introducing liquid refrigerant at the suction
side, until there are no bubbles in the sight glass.
• Signicant undercharge (large bubbles in the sight glass, signi-
cant drop in suction pressure).
- Completely drain the refrigerant charge, using a refrigerant re-
covery unit. After detection and repair check the charge with the
unit off, drain the system and recharge the full amount of liquid
refrigerant (see Table I) on the suction and discharge side.
- The refrigerant container used must contain a minimum of 10%
of its initial charge.
WARNING:
If brazing is to be done, the refrigerant circuit must be lled with
nitrogen.
Combustion of refrigerant produces toxic phosgene gas.
IMPORTANT:
- Never use the compressor as a vacuum pump.
- Always add refrigerant via the suction line.
- Refrigerant must be added very slowly.
- The complete refrigerant charge must never be lled into the
suction line.
- Do not overcharge the system with refrigerant.
Electronic control
Operation and control of all units is carried out via the electronic
control.
The instructions supplied with the control include comprehensive
descriptions.
PRO-Dialog Plus electronic control
PRO-DIALOG Plus is an advanced numeric control system that
combines complex intelligence with great operating simplicity.
PRO-DIALOG Plus constantly monitors all machine parameters and
safety devices, and precisely manages the operation of compressor
and fans for optimum energy efciency.
It also controls the operation of the water pump.
A powerful control system
The PID control algorithm with permanent compensation for the
difference between entering and leaving water temperature and
anticipation of load variations regulates compressor operation for
intelligent leaving water temperature control.
To optimise power absorption, the PRO-DIALOG PLUS automati-
cally re-calibrates the set point of the entering water temperature
based on the outside air temperature to one of the two pre-set val-
ues (occupied building and of an unoccupied building for example).
PRO-DIALOG Plus control is auto-adaptive for full compressor pro-
tection. The system permanently optimises compressor run times
according to the application characteristics (water loop inertia),
preventing excessive cycling. In most comfort air conditioning appli-
cations this feature makes a buffer tank unnecessary.
Clear and easy-to-use control system
The operator interface is clear and user-friendly: LEDs and two
numeric displays ensure immediate verication of all unit operating
data.
10 menus offer direct access to all machine controls, including a
history of possible faults, for rapid and complete chiller fault diagno-
sis.
Extended communications capabilities
PRO-DIALOG Plus allows remote control and monitoring of the
unit through a wired connection: 7-8 x 0.5 mm² multiple cables. The
cable should be screened of the FROH2R or BELTEN 9842 type.
The screening should be grounded only on the electric unit panel
board. Start/stop, cooling/heating mode selection (only 30RH unit),
power demand limit or dual set-point and customer safety lock.
The system permits remote signalling of any general anomaly for
each refrigerant circuit.
Three independent time schedules permit denition of: chiller start/
stop, operation at the second set-point (e.g. unoccupied mode), and
operation at low fan speed (e.g. during the night).
This option also permits cascade operation of two units and remote
control via communication bus (RS 485 serial port).