D
–EIMHP01201-18_06EN - 18/27
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Emptying and cleaning of the heat exchanger during the winter season
It is the responsibility of the installer and/or of local maintenance personnel to ensure that described anti-freeze methods
are used. Make sure that appropriate anti-freeze protection is maintained at all times. Failing to follow the instructions
above could result in unit damage. Damage caused by freezing is not covered by the warranty.
3.9
Installing the flow switch
To ensure sufficient water flow through the evaporator and condenser, it is essential that a flow switch be installed on both
water circuits. The flow switch can be installed either on the inlet or outlet water piping. The purpose of the flow switch is
to stop the unit in the event of interrupted water flow, thus protecting the evaporator and the condenser.
The manufacturer offers, as optional, a flow switch that has been selected for this purpose.
This paddle-type flow switch is suitable for heavy-
duty outdoor applications (IP67) and pipe diameters in the range of 1” to
8
”.
The flow switch is provided with a clean contact which must be electrically connected to terminals shown in the wiring
diagram. Flow switch has to be tune to intervene when the evaporator and/or condenser water flow is lower than 50% of
nominal flow rate.
For a proper unit operation, the water flow-rate of both heat exchangers (evaporator and condenser) must always
recirculate when the unit switch is active (On).
Fig. 7 - Water piping connection
3.10
Minimum system water volume (for Cold and Hot side)
All cold and hot water systems need adequate time to react to a load change. In case of multipurpose unit, the machine
follows the set-point on cold side as well as the se-point on hot side. The control of the heating and cooling capacity of
the unit is achieved by managing the load of the compressors (with VFD) and by cycling each circuit independently
between the following operating modes: cooling only, c heating, and heating only. The potential for short cycling
usually exists when the cooling and heating loads falls below the minimum unit’s capacity or in systems with insufficient
water volumes.
TT
Temperature sensor
TS
Temperature switch
PI
Pressure gauge
FS
Flowswitch
a
Single pump
b
Twin pump
c
Drain
½ ‘’ NPT
d
Automatic filling valve
e
Plugged fitting
¼’’ NPT
f
Safety valve
10 BAR 1/2 ‘’ G
g
Electrical heater
¾’’ G 100 W 230 V
j
Water filter