Viessmann VITOMAX 200-HS Operating And Service Instructions page 16

Operating information
Functions
(cont.)
Pressure monitoring facility rQ to rR
Component
The pressure moni-
toring unit is directly
connected to the
boiler via the fitting
assembly and com-
prises
■ Pressure gauge rQ Operating pressure
■ Pressure limiter rW Protection of the
■ Pressure trans-
ducer rE
■ Straight-through
shut-off valve with
cap rR
16
Function
indicator
boiler against over-
pressure when the
maximum pressure
is exceeded
Load-dependent reg-
ulation of the boiler
combustion subject
to the operating pres-
sure
Enables the replace-
ment of faulty com-
ponents
Operating information
Operating checks at regular intervals
or in accordance with country-specific
regulations
Checking with a calibrated test pres-
sure gauge by an authorised contrac-
tor or test body
Safety chain opened by opening a
contact in the pressure limiter
Burner stops
Safety chain reset by means of the
appropriate key in the control panel.
Reduce the boiler pressure via the air
vent valve or the main steam valve by
approx. 1 bar below the switching
point of the max. pressure limiter and
reset the max. pressure limiter
Burner starts again
Exclusively by authorised contractors