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Maintenance
7.
Maintenance
Caution!
Missing or faulty cleaning and maintenance may cause damage to the instal-
lation.
• The heating installation must be surveyed and cleaned once a year.
• If required, installation maintenance must be carried out. Defects must be
remedied immediately in order to prevent damages to the installation!
7.1 Safety information
Caution!
Sharp edges pose a cutting hazard.
Handle the cladding parts with care and avoid contact with sharp edges.
Caution!
Danger of injury for unqualified personnel.
Maintenance and cleaning work may only be performed by trained personnel
or by the Hoval Customer Service.
Caution!
After repair work respectively exchanging boiler parts, a flue gas measure-
ment according to point 6.7 must be carried out imperatively.
7.2 Bleeding
Open all radiator valves.
Heat up the system for at least half a day with a high flow temperature.
Turn off the boiler and wait 5 minutes.
Bleed all the air from the system.
7.3 Water refilling
The European Standard EN 14868 and the Directive VDI 2035 must be
observed (see point 6.3).
i
The systems warns when the water pressure falls below 1 bar and the boiler
output is reduced to 50%. If the water pressure falls below 0.5 bar, the boiler
is set automatically to a fault state.
The system must be refilled with water when the pressure falls below the
minimum system pressure:
Connect the filling hose to the water supply.
Remove the air from the filling hose.
Connect the filling hose to the filling and draining cock.
Top up with water (see point 6.2).