11 Buffer tank
account within the time release. This means that the
pump is only cycled if the recirculation temperature is
below the
required recirculation temperature
of minus
5°C.
Example:
- Release type =
Monday-Sunday
- The recirculation control currently has, for example, a
time release of 06:00 to 08:00
- Switch-on duration = 30 seconds
- Hold-on time = 4 minutes
- Required recirculation temperature = 50°C
- Recirculation temperature = 48°C
The recirculation pump is not triggered as the recir-
culation temperature (48°C) is above the
required recir-
culation temperature
of minus 5°C (50°C minus 5°C =
45°C). If the recirculation temperature goes below
45°C, the recirculation pump is triggered for 30
seconds. After this, the pump pauses for 4 minutes in
order to then run for 30 seconds again. This repeats
until the recirculation temperature reaches the
required
recirculation temperature
. Outside the time release,
the pump is not triggered.
10.2.3 Extension of recirculation by means of a
flow impulse
Recirculation being controlled by a flow impulse
3
is
only possible in fresh water modules
, and is used
as an extension of the control options previously
named.
In order to activate this function, the
Flow Impulse
3
parameter must be set to
on
. When a hot water extrac-
tion point is opened briefly, an electronic sensor
detects the pressure drop in the line. The recirculation
pump is triggered even if there is no time release.
Exception: If a temperature sensor for the recirculation
pump (=recirculation sensor) is connected and the
recirculation temperature us sufficient (see
Tem-
perature- and time-controlled recirculation
), then the
recirculation pump is not triggered.
Example:
- Release type =
Monday-Sunday
- No time release has been set.
As soon as DHW is drawn, the recirculation pump is
triggered.
11 Buffer tank
Fig. 2-37_09-002-02
1 Buffer cylinder temperature top
2 Temperature of the energy source
3 Buffer cylinder temperature bottom
4 Info line: Heating requirement (Yes/No) to the
energy source.
5 Buffer tank settings
Button is only visible when
Timer
is selected as the buffer
cylinder operating mode; only qualified personnel may set
it.
6 Buffer tank status line
Set buffer tank temperatures
Min. buffer temp. top
When
Buffer cylinder temperature top
falls below this
value, the energy source for the buffer cylinder starts
(e.g. boiler) and the buffer cylinder is re-charged (upon
time release).
Max. buffer temp. Down
The buffer tank is charged until the
Buffer tank tem-
perature bottom
has reached this value.
i
In order to ensure optimum and efficient use of
the buffer tank, the difference between these
two temperatures should be > 15°C.
28
Operation manual
therminator II touch
