Ravenheat 780 Series, Instructions For Use Installation And Servicing

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-- Continue filling the system until 1.5 bar
register on gauge. Then turn off the filling
points stopcock.
- Inspect the system for water soundness and
remedy any leaks discovered.
6.5 SETTING THE SYSTEM DESIGN PRESSURE
The design pressure must be a min. 1 bar and
max. 1.5 bar. These figures are read off the
pressure gauge.
- The actual reading should ideally be 1
bar + the height in metres to the highest
point of the system above the base of the
appliance (up to max of 1,5 bar).
N.B.: The safety valve is set to lift a 3 bar.
- To lower the system pressure to the
required value remove drain point (fig. 45)
or drain on the heating circuit.
6.6 FILLING THE HOT WATER SYSTEM
Close all hot water draw-off taps.
Open the cold water inlet cock.
Slowly open each draw-off tap until clear water
is discharged.
6.7 LIGHTING THE BOILER
Before lighting the main burner make sure that
the heating circuit flow and return valves are
open and also that the cold water input cock is
open.
- If external controls are installed (e.g
timeclock and thermostat) make sure that
they call for heat.
- Turn main switch (fig. 37 item 1A) to winter.
SECTION 6
COMMISSIONING
6.1 Each boiler has been through a rigorous
operational procedure at our factory and
should not require any further adjustment
If in the unlikely event of the appliance not
operating correctly, please turn to the Fault
Finding and Logic Sequence Charts.
6.2 GAS SUPPLY INSTALLATION
6.2.1 Inspect the entire installation including the
gas meter, test for soundness and purge, all
as described in BS 6891.
6.3 ELECTRICAL INSTALLATION
Preliminary electrical systems checks to
ensure electrical safety shall be carried out
by a competent person (earth continuity,
polarity, resistance to earth). Those checks
are outlined in the «Instructions for British Gas
Multimeter» Booklet. If a fault has occurred
on the appliance the fault finding procedure
should be followed as specified under the
servicing section of this document.
6.4 INITIAL FILLING OF THE SYSTEM
Open central heating flow and return valves
Unscrew the cap on automatic air release
valve one full turn (leave open permanently).
- Close all air release taps on the central
heating system.
- Gradually open stopcock at the filling point
connection to the central heating system
until water is heard to flow.
Starting with the lowest radiator open each
air release tap in turn. Close it only when
clear and free of bubbles, flowing out in
the water is the same way release air from
any high points in the pipework.
Fig. 36/a