Viessmann VITOMAX 200-HS Operating And Service Instructions page 13

Functions
(cont.)
Level monitoring water level "too low" (NW electrode qW)
Level electrode to safeguard against minimum water levels
Function
Self-monitoring low water indicator
comprising
■ Two level electrodes
■ The associated evaluating devices
Safety valve wP
Function
■ Physical protection of the boiler
against pressures in excess of the
max. permissible operating pressure
P1
■ Valve response pressure = max. per-
missible steam boiler operating pres-
sure
Testing/checks
Operating checks in regular intervals or
in accordance with country-specific
regulations
Regular checking by an authorised con-
tractor or test body
Operating condi-
tion
Standard water
level
Water level too low Electrode is out of the
The minimum boiler
water content is
achieved again
■ Valve discharge capacity ≥ max.
steam output (boiler)
■ Pressure increase max. P1 plus 10%
with max. blow-off rating
■ Closing pressure at P1 minus 10 %
Operating information
Briefly cracking open by lifting the lever –
Do not release the lever.
Note the manufacturer's operating instruc-
tions
Never remove the lead seal
Operating information
Operating informa-
tion
Electrode is immersed
into the conducting
boiler water and regis-
ters a low resistance
Safety chain closed
Burner operation ena-
bled
boiler water and regis-
ters a high resistance
Safety chain and
burner operation con-
stantly interrupted
Re-enable safety chain
Burner block lifted
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