Installation guide

25
VMBME102
11.4 Heating
Heating is active when the outdoor temperature is the same as or greater than 17°C (adjustable value for HEAT STOP) and other operating condi-
tions are met, see the “Operating conditions ” section for more information. When the outdoor temperature is greater than 17°C heating stops.
Figure 45: Operating conditions for heating (The values between brackets are the default values).
The figure above shows DHP-AL operating for heating. When heating during the winter months, the outdoor unit’s air heat exchanger is
cooled by the energy exchange at the same time as the humidity causes it to become covered in frost. DHP-AL has an automatic function
to defrost the air heat exchanger using the produced heat energy. If necessary, a defrosting sequence starts which means the following:
• The defrosting sequence starts when the temperature of the brine reaches its set parameter for defrosting
• The compressor runs when a start signal initializes the defrosting sequence
• An exchange valve in the heat pump shifts the direction of flow of the brine so that the fluid flows through the water heater jacket
where the heated brine is stored
• The heated brine melts the frost on the outside of the air heat exchanger
• When the brine returns from the outdoor unit, a temperature of 11°C is maintained so that the air heat exchanger is defrosted sufficiently
• The exchange valve shifts back the direction of flow of the brine so that normal flow can be resumed
• Operation returns to normal heating
11.5 Auxiliary heater 400V
The auxiliary heater is made up of an electric heating element on the supply pipe that has three outputs, ADD.HEAT 1, ADD.HEAT 2 and
ADD.HEAT 3, and can be controlled in five steps:
• Step 1 = ADD.HEAT 1 = 3 kW
• Step 2 = ADD.HEAT 2 = 6 kW
• Step 3 = ADD.HEAT 1 + ADD.HEAT 2 = 9 kW
• Step 4 = ADD.HEAT 2 + ADD.HEAT 3 = 12 kW
• Step 5 = ADD.HEAT 1 + ADD.HEAT 2 + ADD.HEAT 3 = 15 kW
In the event of an alarm, the auxiliary heater engages automatically.
11.6 Auxiliary heater 230V
The auxiliary heater is made up of an electric heating element on the supply pipe that has two outputs, ADD.HEAT 1 and ADD.HEAT 2, and
can be controlled in three steps:
• Step 1 = ADD.HEAT 1 = 1.5 kW
• Step 2 = ADD.HEAT 2 = 3 kW
• Step 3 = ADD.HEAT 1 + ADD.HEAT 2 = 4.5 kW
In the event of an alarm, the auxiliary heater engages automatically.
Outdoor temperature
Heating not permitted at outdoor tempera-
ture greater than HEAT STOP.
Heating permitted with compressor + addition
between HEAT STOP and OUTDOOR STOP.
Heat production permitted only with addition
at outdoor temp. lower than OUTDOOR STOP.
HEAT STOP (17°C)
OUTDOOR STOP (-20°C)
Time
Supply tem-
perature
Time
Only additionCompressor + addition if necessary Compressor + addition if necessary
MAX (55°C)
Start compr.
Stop compr.