17. Annual Maintenance Cont.
17.5 Checking the pressurization in the expansion vessel:
Empty the central heating system as described in section 17.3 of this chapter and check
that the pressure in the expansion vessel is not less than 1 bar (14.5 psi). See also
section 13.2 page 26 of this manual. If the pressure should be lower, take steps to correct
the pressure level.
17.6 Cleaning the burner:
The sloping and multi-gas type burner (7 on page 11) does not need special maintenance,
but it is sufficient to dust it with a bristle paintbrush.
17.7 Checking the flue:
Have the integrity of the flue outlet pipe (24 on page 12) air intake pipe (25 on page 12),
checked periodically, the venturi device (23 on page 12) cleaned and the efficiency of the
flue safety circuit checked at least once a year. For all the above maintenance operations
it is advisable to call an approved Service Engineer.
To check the pressure at the venturi device, use the test points (12 on page 11).
• Remove the caps of
the pressure test
points and connect a
differential pressure
gauge.
• Switch on the boiler
• Compare the value on
the gauge with the
minimum values of
venturi pressure
indicated in the
Section 2 on page 10.
Venturi test
points
Figure 17.4
17.8 Visual inspection of appliance:
Visually inspect all water joints, seals and connections for any evidence of leakage and
retighten, grease or replace them as necessary.
17.9 Gas pressures and soundness:
Check appliance for gas soundness. Recheck operational pressures and adjust as
necessary as described in Section 15.4 page 32 of this manual.
RIVA HEAT ONLY MANUAL - REV A
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