Daikin E8.5064, Installation Manual

Page: 47 / 48

Glossary
47
Glossary
Flow and return flow temperature
The flow temperature is the temperature to which the heat
source heats the water that transfers the heat to the con-
sumer (e.g. radiator). The return flow temperature is the
temperature of the water that flow back from the consumer
to the heat source.
Desired and actual temperature
The desired temperature (or setpoint temperature) de-
scribes the desired temperature for a room or for hot wa-
ter.
The actual temperature denotes the actual temperature
that prevails. The heating controller has the task to adjust
the actual temperature to the desired temperature.
Setback temperature
The setback temperature is the desired temperature to
which the heating system heats outside heating times
(e.g. at night). It should be set so that the rooms do not
cool down too much while saving energy.
Heat source
Heat source is generally the designation for the heating
boiler. It may also be a buffer storage tank however.
Mixed heating circuit/Mixer circuit
In the mixed heating circuit a three-way valve is used to
add cooled water from the return flow to the hot flow water.
The flow temperature is thus reduced. This is important for
Underfloor heating systems, for example, because they
must only be operated with low flow temperatures.
Heating time
In the heating programs you can define up to three heating
times per day, one for the morning, one for lunchtime, and
one for the evening for example. During a heating time, the
temperature is controlled to the desired room temperature.
Between heating times the temperature is controlled to the
setback temperature.
Header pump
A header pump is used to pump the hot water in a system
with one or several heat sources. It is switched on as soon
as a consumer in the system requests heat.
Legionella
Legionella are bacteria that live in water. The hot water
storage tank is heated to 65 °C every 20th heating period
or at least once a week as protection against these bacte-
ria.