15
Mynute 24m
5.1
GAS SUPPLY INSTALLATION
Inspect the entire installation including the gas
meter, test for soundness and purge. Refer to BS
6891 for specific instruction.
5.2
THE HEATING SYSTEM
The appliance contains components that may
become damaged or rendered inoperable by oils
and/or debris that are residual from the installation
of the system, consequently it is essential that the
system be flushed in accordance with the follow-
ing instructions.
5.3
INITIAL FILLING OF THE SYSTEM
Ensure both flow and return service valves are
open, remove appliance casing as described in
4.7.1, identify the automatic air release valve and
loosen the dust cap by turning cap anticlockwise
one full turn. IMPORTANT, THERE ARE NO
MANUAL AIR RELEASE VALVES LOCATED ON
THE APPLIANCE. Ensure all manual air release
valves located on the heating system are closed.
Using the method of filling as described in fig. 5,
slowly proceed to fill the system. As water enters
the system the pressure gauge will begin to rise,
Once the gauge has reached 1 bar close the filling
valve and begin venting all manual air release
valves, starting at the lowest first. It may be
necessary to go back and top-up the pressure until
the entire system has been filled. Inspect the
system for water soundness, rectifying any leaks.
5.4
INITIAL FLUSHING
The whole of the heating system must be flushed
as detailed in 5.8. Open all radiator or heating
valves and the appliance flow and return service
valves. Drain the boiler and system from the
lowest points. Open the drain valve full bore to
remove any installation debris from the boiler prior
to lighting. Refill the boiler and heating system as
described in 5.3.
5.5
PRE-OPERATION CHECKS
Before attempting the initial lighting of the appli-
ance, the following checks must be carried out:
•••••
ensure all gas service valves from the meter to
the appliance are open and the supply pipe has
been properly purged;
•••••
ensure the proper electrical checks have been
carried out (section 7.7), particularly continuity,
polarity and resistance to earth;
•••••
ensure the 3-amp fuse - supplied with the appli-
ance - has been fitted;
•••••
ensure the system has been filled, vented and
the pressure set to 1bar;
•••••
ensure the flue system has been fitted properly
and in accordance with the instructions;
•••••
ensure all appliance service valves are open.
5.6
INITIAL LIGHTING
Ensure the electrical supply to the appliance is
switched on. Switch the time clock or programmer
(if fitted) to an “on” position and ensure all external
controls are also calling for heat.
SECTION 5 COMMISSIONING
Turn the mode selector knob to be “on” position
(fig. 1). The appliance will now go through an
ignition sequence as described in 1.2. Should the
appliance fail to ignite, refer to section 5.5 and/or
section 7 (fault finding).
5.7
CHECKING BURNER PRESSURES
Although the burner pressure is factory set, it is
necessary to check it during the commissioning.
Isolate the appliance from the electrical supply
and attach a suitable manometer to the gas valve
outlet test nipple (fig. 17). Light the boiler as
described in 5.6 and compare the reasging on the
manometer with the value described in 2.2. If
adjustment is required, follow the detailed instruc-
tions in section 7 (7.3). Once the burner pressure
has been checked, isolate the appliance from the
electrical supply, remove the manometer and
tighten the gas valve outlet test nipple.
5.8
FINAL FLUSHING OF THE HEATING SYSTEM
The system shall be flushed in accordance with
BS 7593. If a cleanser is to be used, it shall be from
a reputable manufacturer* and shall be adminis-
tered in strict accordance with the manufacturers
instructions.
*Both Sentinel and Fernox manufacture products
that have proved suitable for use with Vokera ap-
pliances. Vokera Ltd. cannot comment on the suit-
ability of any other such product with our appli-
ance.
5.8.1
INHIBITORS
See 3.8.
5.9
SETTING THE BOILER OPERATING TEMPERA-
TURE
The flow outlet temperature can be adjusted be-
tween 40ºC - 80ºC via the thermostat knob (fig.1).
5.10
SETTING THE SYSTEM DESIGN PRESSURE
The design pressure should be a minimum of 1 bar
and a maximum of 1.5 bar.
The actual reading should ideally be 1 bar plus the
equivalent height in metres (0.1 BAR = 1 metre) to
the highest point in the system above the base of
the appliance (up to the maximum of 1.5 BAR
total).
N.B. The safety valve is set to lift at 3 BAR/
30metres/ 45psig.
To lower the system pressure to the required
value, pull lever on head of safety valve to release
water until the required figure registers on the
pressure gauge (fig.1).
5.11
REGULATING THE CENTRAL HEATING SYS-
TEM
Fully open all radiator and circuit valves and run
the appliance for both heating and hot water until
heated water is circulating. If conditions are warm
remove any thermostatic valve heads. Adjust
radiator return valves and any branch circuit return
valves until the individual return temperatures are
correct and are approximately equal.
