Unit installation

Use and Maintenance Manual Air-cooled water chillers and Heat Pumps R-PAE/R-PAH/EAH Rev. 1 del 03/09
Ø The unit must be connected to the hydraulic system by using the appropriate areas as indicated in the
commercial drawing here attached.
Ø The diameter of the hydraulic connections are shown in the commercial drawing here attached.
For the connections dimension, see the commercial drawing here attached.
4.5.1 Evaporator
For the connection of pipes to the evaporator, it is advisable to follow the instructions listed here below:
Ø Connect the pipes as shown in the diagram in Picture 32;
Ø Employ anti-vibration pipe fittings to avoid any vibration transmission and to allow the thermal expansion;
Ø Install on the water inlet a filter with grid not larger than 1 mm and with a bigger diameter than the pipe
diameter;
Ø Place the air discharge valves in the appropriate points of the hydraulic system;
Ø Install a ball check valve on the inlet and outlet so that it is possible to shut off the unit in case of special
maintenance operations. The installation of three-piece joints between the valves and the chiller will ease
these operations;
Ø The water system pressure must range between 1,5 and 3,5 bar.
Ø In case of low evaporating temperatures (< 4°C) it is recommended to employ anti-freeze mixtures
(glycol) as shown in the following tables, according to the kind of glycol used:
Picture 32 - Piping connection diagram
If the unit is not equipped with a water pressure switch (optional), it is recommended to install a
safety flow switch on the hydraulic system so that the unit can be shut off in case the water flow to
the exchanger is insufficient. This device must be connected to the relevant terminals inside the
electric panel (see the attached wiring diagram).
If the anti-freeze mixture contains a lower ethylene glycol percentage than below recommended, there could be risks of
freezing, while a higher percentage can reduce the unit performance. At the beginning of every winter, it is recommended to
check the correct concentration of glycol in the system.
Do not use anti-freeze liquids unsuited to copper, stainless steel and to all other materials present in the system.
The cooled water system must be heat insulated with closed-cells material having adequate features
of heat insulation and steam resistance for the unit operating conditions.
25
Ethylene glycol percentage on the mixture weight
Description
5% 10% 15% 20% 25% 30% 35% 40%
Freezing
temperature
-2,1 -4,5 -7 -10 -13 -17 -21 -25