Viessmann VITOROND 100 Installation And Service Instructions Manual page 71

Service Procedure
8. Ensure proper operation of expansion tank, low water cut-off (if applicable) and pumps
Refer to maintenance instructions
supplied with diaphragm expansion
tanks, low water cut-offs, pumps, etc.
Flush float water type low water
cut-offs (if used).
9. Ensure that an adequate combustion air supply exists in the boiler room
10. Ensure functionality of the barometric draft regulator of the burner
(continued)
The usual water fill pressure is between
10 and 15 psi with the system cold. A
lower pressure gage reading usually
indicates loss of water due to leakage.
All leaks must be corrected. Refer to
instructions packaged with automatic
fill valve. Follow local regulations with
respect to backflow preventers.
If oil-lubricated pumps are used, ensure
proper lubrication.
If motorized zone valves are used, refer
to maintenance instructions provided
with zone valves.
If an older non-diaphragm expansion
tank is used, ensure the correct water
level is present.
Ensure fresh air intake of boiler room is
open. This opening must never be
blocked or partially covered.
During operation of the burner, the
barometric draft regulator installed in
the vent system must move freely.
Service
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