3
2
1
19
18
17
15
14
16
11
13
12
10
9
8
7
6
5
4
Position Description
Position Description
1
Compressor
11
Electronic expansion valve
2
Operating pressure switch
12
Non-return valve
3
High pressure switch
13
Solenoid
4
Discharge pipe sensor
14
Refrigerant sensor 2
5
Four-way valve
15
Air exchanger (evaporator)
6
Heating system (cold return line)
16
Fan
7
Plate heat exchanger (condenser)
17
Refrigerant sensor 1
8
Heating system ( hot supply line)
18
Pressure transmitter
9
Receiver
19
Temperature transmitter
10
Drying filter
The heat pump can produce heat for heating (house, pool), hot water and cooling. The hot water requirement is
prioritised before the heating requirement and cooling requirement. The heating requirement is calculated from
outdoor temperature and set heat curve.
For a fuller description of heat curves etc., seeImportant parameters, Page 39.
4.5
Hot water function
The water heater is equipped with a TWS coil (Tap Water Stratificator). The hot water is led from the heat pump
through the water heater in the TWS coil from the top down. In this way the upper section of the water heater,
where the hot water is tapped from, is always heated first.
Heating the hot water in the water heater is not stopped by the temperature but via the pressure in the refrigerant
circuit of the heat pump unit. The operating pressure switch on the pressure pipe breaks at 28.5 bar. This means
that heat pumps in different output classes may have slightly different peak temperatures for hot water. As a rule
the peak temperature is between 54 – 58°C in a 180-litre water heater. Thanks to the design of the water heater
and the TWS coil the hot water layers itself so that the hottest water is always at the top of the water heater and
the cooler water at the bottom.
Two sensors indicate the present temperature of the hot water to the heat pump controls. A top water sensor that
is located in the top of the water heater, and a hot water sensor located approx 50 cm up from the bottom of the
water heater. Both the sensor values are ”weighted” where the hot water sensor influence is 65 % (factory setting,
18 – Installation instructions VMGFD102
