Checking All Gas Connections For Leaks; Checking The Flue Side Gaskets/Seals; Flue Side Gaskets/Seals - Viessmann Vitocrossal 200 CM2 400 Service Instructions Manual

Vitocrossal 200, CM2 400, 500, 620 and 620 TX Service
Steps – Commissioning, Inspection and Maintenance

Checking the Flue Side Gaskets/Seals

Commissioning, Inspection, Maintenance

Checking all gas connections for leaks

The burner control unit automatically checks the valves for
tightness when the burner is started. If the valves are gas
tight, the burner enters standard mode and the burner starts.
If the first valve is not tight, fault code "F E1" is shown on
the burner control unit display; if the second valve is not tight,
fault code "F E2" is displayed. In either case, the gas valve
must be replaced.
WARNING
Escaping gas leads to a risk of explosion. Always carry
out the following steps.
1. Insert new gaskets in all gas fittings that have been
opened and then tighten those fittings.
2. Open the gas shut-off valve.
3. Check the inlet seals of the gas valve for tightness.
4. Start the burner.
5. Check the outlet seals of the gas valve and fittings
between the fan and the boiler door and between
the fan and the venturi pipe for tightness.
Note: The use of leak detecting spray can result in
incorrect functions. Leak detecting spray must
not come into contact with electrical components.

Flue side gaskets/seals

1. Remove the rear panels from the boiler and disconnect
the venting system from the flue gas collector.
Refer to the Installation Instructions for details.
2. Check that the flue gas collector C is tight to the
boiler A. If required, retighten the flue gas collector
mounting fasteners D. Torque to 7.4 lb/ft (10 Nm).
3. Reconnect the venting system with the flue gas pipe
adaptor and tighten with gear clamps.
Note: The seals/gaskets can also be checked under full
load with an inspection mirror. If required, remove
the thermal insulation components. Traces of
condensate on the outside of flue gas collector C
also point towards a leak.
CAUTION
Failure to ensure that all flue gases have been safely
vented to the outdoors can cause property damage,
severe personal injury or loss of life. Flue gases may
contain deadly carbon monoxide.
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