Viessmann VITODENS 300 Service Instructions Manual page 25

Further details regarding the individual steps
Flow limiter (only for gas combination boilers)
Checking all gas equipment for soundness at operating pres-
sure
Danger
Escaping gas leads to a risk of
explosion.
Check gas equipment for
soundness.
Initial start-up, inspection, maintenance
(cont.)
1. Switch OFF the control unit, shut off
the cold water supply line and drain
the secondary (DHW) side of the
boiler.
2. Release Allen screws A.
Note
Residual water may escape during
dismantling.
3. Remove flow switch B and remove
flow limiter C downwards.
4. Check flow limiter C; replace in
case of excessive calcination or
damage.
Secure flow switch B (torque: 1
Nm).
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