Checking The Water Quality; Checking The Safety Valve Function; Checking The Temperature Controller Setting If A Building Management System Is Used (Dcc System); Checking The Expansion Vessel - Viessmann Vitocrossal 200 Service Instructions For Contractors

Checking the water quality

Enter the amount of top-up water, the total hardness and the pH value in the tables on page 72.
For water quality requirements, see page 70.

Checking the safety valve function

Checking the temperature controller setting if a building management system
is used (DCC system)
!
Please note
Shutting down from full load can result in high
material stress and material damage.
If a system with a higher ranking building man-
agement system takes over the temperature
control of the boiler, adjust the settings at the
temperature controller TR. Set the electronic
temperature controller to at least 10 K below the
mechanical temperature controller.

Checking the expansion vessel

Note
Observe the manufacturer's instructions for the expan-
sion vessel.
Carry out this test on a cold system.
1. Drain the system until the pressure gauge indi-
cates "0" or close the cap valve on the expansion
vessel and reduce the pressure in the expansion
vessel.
2. If the expansion vessel pre-charge pressure is
lower than the static system pressure, top up with
nitrogen. Top up with nitrogen until the pre-charge
pressure is 0.1 to 0.2 bar (10 to 20 kPa) higher.

Checking the mixer for ease of operation and leaks

1. Remove the motorised lever from the mixer han-
dle.
2. Check the mixer for ease of operation.

Checking the thermal insulation for firm seating

Checking the installation room ventilation air apertures
Check that the vent is unobstructed and free from con-
tamination.
Commissioning, inspection, maintenance
3. Top up with water. The charge pressure of the
cooled system must be 0.1 to 0.2 bar (10 to
20 kPa) higher than the pre-charge pressure of the
expansion vessel.
Permiss. operating pressure: 6 bar/0.6 MPa
3. Check the mixer for leaks. Replace the O-rings if
the mixer leaks.
4. Click the motorised lever into place.
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