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Vitocrossal 300 CU3A 26 to 199 Service
Example Layout 1
DHW heating by the solar thermal system
Solar circuit pump
wE
starts and DHW tank
qR
is heated
up, if the temperature differential between collector
temperature sensor
wQ
and tank temperature sensor
qT
exceeds the start temperature differential.
Pump
wE
is stopped according to the following criteria:
H
The actual temperature drops below the stop
temperature differential
H
Exceeding the electronic temperature limit
(up to 90°C) set in the solar control module
(type SM1)
wZ
H
The temperature selected at high limit safety cut-out
qZ
(if installed) is reached
Demands for the auxiliary function are met by
circulation
pump
wR
.
Suppression of reheating of the DHW tank by the boiler
in conjunction with solar control module (type SM1)
Reheating suppression takes place in two stages.
Reheating DHW tank
qR
by boiler
1
is suppressed
as soon as DHW tank
qR
is heated by collectors
wP
.
For this, the set tank temperature for reheating is
reduced by boiler
1
. Suppression remains active for
a certain time after solar circuit pump
wE
has been
switched off.
In the case of uninterrupted heating by collectors
wP
(>2 h) boiler
1
will only reheat, if the set tank
temperature (coding address “67”) selected at boiler
circuit control unit
2
is not achieved.
In control unit
2
, coding address “67” defaults a third
set DHW temperature (setting range 10 to 95°C). This
value must be below the first set DHW temperature.
DHW tank
qR
will only be heated by boiler
1
when
this set value is no longer achieved by the solar thermal
system.
Matching the control unit to the heating system
Subject to the equipment level, the control unit must
be matched to the system. Various system components
are recognized automatically by the control unit and the
relevant codes are adjusted automatically.
H
For the selection of an appropriate scheme,
see the following diagrams.
H
For coding steps, see page 55.
System version 1
One heating circuit without mixing valve and DHW
heating (optional solar DHW heating)
Applications
Heating system with DHW heating
Main components
H
Gas condensing boiler models 26 to 199
H
DHW tank (dual mode)
H
Solar thermal system
Function description
The boiler circuit
eP
and the DHW tank
qP
/
qR
are regulated
by boiler heating circuit controller
1
. The heating circuit
and the DHW tank are supplied by their individual circulation
pumps
eQ
and
qE
.
Heating mode
The boiler heating circuit controller regulates the boiler
water temperature in weather-compensated or heat
demand dependent mode (= supply temperature of the
heating circuit without mixing valve).
DHW heating without a solar thermal system
If the temperature falls below the set DHW temperature
selected at control unit
2
, the burner of boiler
1
starts
and circulation pump
qE
of DHW tank
qP
or
qR
runs.
Within the program set at control unit
2
, DHW is heated
with or without priority.
Function/system
components
Code
Adjust
Delivered condition
Operation with LPG
82:1
82:0
Service