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Every 3000 hours / annually
Cleaning and maintenance
Check whether the fork of the heat exchanger ash
screw is evenly flush on the sealing ring. Also check
the movement by pushing the ash screw in the axis
direction.
1
Washer
2
Fork of the heat exchanger ash screw
Clean the lambda probe
Use a pipe wrench to unscrew the lambda probe's
retaining tube.
Fig. 2-51: Retaining tube
Remove the lambda probe and the enclosed sealing
ring from the boiler.
Let the lambda probe cool off and clean it with a
vacuum cleaner. Take special care to clean the
openings in the head of the lambda probe.
Fig. 2-52: Lambda probe
Clean the lambda probe's seal seat in the boiler.
It must be absolutely clean. Check it with a torch
and clean out the coupling with a vacuum cleaner.
The washer for sealing the lambda probe's metal
flange and the seat in the boiler must be replaced
when installing the probe.
Fig. 2-53: Washer
Tighten the lambda probe's retaining tube firmly with a
pipe wrench (with 20 kg at 20 cm lever length).
Checking the safety valves
Perform a visual inspection of all safety valves of the
heating system. The outlets of the safety valves may
not drip.
Fig. 2-54: Safety valve
Perform this step only on weekdays, never on
weekends during a cold winter, as there will
probably be no heating technician available if the seal
is defective.
If the safety valve drips, open it with a quarter turn of
the red cap and rinse it out (danger of scalding). If the
safety valve still cannot be sealed effectively after
being rinsed several times, it must be cleaned by a
technician or replaced.