Boiler Water Temperature Control Of The Vitotronic 200; Cascade Control Of The Vitotronic 300-K - Viessmann VITOTRONIC 200 Installation And Service Instructions Manual

Vitotronic 200, HO1B and 300-K, MW2C Installation/Service

Boiler Water Temperature Control of the Vitotronic 200

Cascade Control of the Vitotronic 300-K

Function Description, Vitotronic 200/300-K
Brief description
H The boiler water temperature is regulated by modulating
burner up or down as required.
H The set boiler water temperature is defaulted by the
Vitotronic 300-K.
Functions
The boiler water temperature is recorded separately:
H Temperature limiter
H Boiler water temperature sensor
Upper control range limits
Electronic maximum boiler water temperature limit:
H Setting range: 68°F (20°C) up to boiler coding card
default
H Changes at coding "06" in the "Boiler" group
Control sequence
The boiler goes cold:
H The burner start signal is set for set boiler water
temperature -7°F (-4 K) and the burner starts its own
monitoring program.
H You can delay the burner start by several minutes.
Boiler heats up:
H The burner shutdown point is determined by the
shutdown differential of 15°F (8 K).
Brief description
H The supply temperature is regulated by starting or
stopping the burner or by modulating the individual
burners.
H The boilers will be regulated to the set boiler water
temperature defaulted by the cascade control unit
(standalone control).
H Subject to the system design, you may select between
one condensing strategy and two conventional boiler
strategies.
H The boiler sequence (see page 31) can be determined
at coding level 2 and the boiler sequence selection.
For boiler sequence selection refer to the
Operating Instructions of the Vitotronic 300-K.
H Coding that influence the cascade control: "Cascade"
group. For a description, see coding overview.
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