Check Flow Rate Limiter And Water Flow Switch Filter; Check Diaphragm Expansion Tank And System Pressure - Viessmann Vitodens 200 Start-Up/Service Instructions

Vitodens 200 WB2 Service

Check Flow Rate Limiter and Water Flow Switch Filter

Check Diaphragm Expansion Tank and System Pressure

(for Combi boiler only)
1. Loosen threaded connection of the cold water pipe
at the water flow switch A.
2. Loosen threaded connection at the cold water
connection nipple B.
3. Take out cold water connection nipple C with the
water filte D.
4. Check the flow rate limiter E in the connection
nipple C; if limescale is present or if damaged,
replace connection nipple.
5. If required, clean water filter D. Apply moderate
amount of supplied lubricant to gasket/O-ring.
6. Reassemble in reverse sequence.
Perform check with the system cold.
1. Drain boiler/system and reduce pressure until the
manometer reading is "0".
2. If the nitrogen pressure of the precharged expansion
tank is less than the static pressure of the system,
inflate membrane pressure to slightly exceed pressure
of system.
The static pressure required at the tank is based upon
the static height of the system. The system fill
pressure value must be equal to the expansion tank
pressure value at approx. 60ºF/15.6ºC.
Example:
Static head of 33 ft./10 m (distance between boiler
and topmost heat emitter surface) corresponds to a
static pressure of 1 bar/15 psig.
3. Top up with water until filling pressure is higher than
the inlet pressure of the diaphragm expansion tank.
With the system cold, the filling pressure must be
approx. 3 psig higher than the static pressure.
Max. operating pressure: .............45 psig
Min. operating pressure: ..............12 psig
4. When starting up the system for the first time, mark
this value as the minimum filling pressure on the
manometer. A lower manometer reading usually
indicates loss of water due to leakage. All leaks must
be repaired.
Start-up and Service
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