Conversion To Natural Gas (Ng) - Viessmann Vitocrossal 200 CM2 186 Service Instruction

Commissioning, Inspection and Maintenance
Steps – Commissioning, Inspection and Maintenance

Conversion to natural gas (NG)

1. Close the gas shut-off valve.
2. Switch OFF the system ON/OFF switch at the boiler
control unit.
3. Switch OFF the main boiler circuit breaker (outside
the boiler room) or the power supply and prevent
unauthorized reconnection.
4. Remove boiler front cover.
5. Undo gas supply fitting A.
6. Disconnect compensation tubing B connected
between the venturi tube and the gas valve.
12
Vitocrossal 200 CM2 186 to 311 Service
(continued)
7. Remove four 8 mm hex nuts. Detach the gas valve
from flange C.
8. Remove and dispose of the LPG orifice D (with pin)
and the rubberized cork gaskets E. Install a new
rubberized cork gasket between the gas valve and
flange C.
Note: No separate orifice is necessary for Natural Gas.
9. Secure gas valve, to the flange of the mixing system
C. Torque nuts diagonally with 17.7 lb.in (2.0 Nm).
10. Secure and tighten gas supply fitting A.
11. Reconnect the compensation tubing B (connected
between the venturi tube and the gas valve).
12.Apply:
- Partial rating plate above CSA rating plate located
on top panel (behind the boiler control).
- Label F indicating that this unit is equipped for LPG
over the NG label located on the gas valve.
- Label indicating that this unit has been converted from
NG to LPG next to the CSA rating plate (on the top
panel).
- Fill out and fax conversion report.
13.Check all gas fittings for leaks.
WARNING
Escaping gas leads to a risk of explosion.
Check all fittings for gas leaks.
Note: The use of leak detecting spray can result in
incorrect functions. Leak detecting spray must
not come into contact with electrical components.
Note: For commissioning, see page 10. Switch the burner
to maximum heating output. For this, activate the
emissions test switch at the boiler control unit.