3.5
Water heater
Thermia heat pumps Diplomat and Comfort are supplied with an integrated 180 litre water heater. They are
equipped with a TWS coil, which results in more effective heat transfer and more efficient layering of the water
in the water heater.
1
2
3
4
5
7
8
6
1
Tap hot water
2
Top temperature sensor
3
Water heater
4
TWS coil
5
Start temperature sensor
6
Supply line to TWS coil
7
Return line from TWS coil
8
Cold water line
Hot water production is prioritised over heat production.
The temperature of the hot water cannot be adjusted. Hot water production does not stop at a preset water
temperature; it stops when the compressor’s operating pressure switch reaches its maximum pressure. This
corresponds to a hot water temperature of approximately 50–55°C in normal conditions.
To prevent the build up of bacteria in the water tank, the temperature of the water is increased at regular inter-
vals using the integrated electrical heater (anti-legionella function). The factory-set time interval is seven days
(can be adjusted). When the anti-legionella function is active, the heat pump produces hot water until the tem-
perature for the start temperature sensor (5) has reached 60°C.
In the control system’s TEMPERATURE menu, the temperatures that are measured and calculated for the hot
water and heating system supply line are displayed. The current temperature of the top temperature sensor (2)
and the temperature of the supply line during heating and hot water production are displayed. The tempera-
ture of the supply line often exceeds the maximum permitted hot water temperature, usually during hot water
production.
The hot water tanks for Atria differ from the other heat pumps as the function for defrosting the outdoor unit is
different.
User Guide
Domestic heat pumps
Thermia Värmepumpar
VUGFD202
9
