VOKERA Mynute i20, User Instructions

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18
5.1 GAS SUPPLY INSTALLATION
Inspect the entire installation including the gas meter, test for
tightness and purge. Refer to BS 6891 (I.S. 813 in ROI) for
specifi c 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 fl ushed in accordance with the following
instructions.
5.3 INITIAL FILLING OF THE SYSTEM
Ensure both fl ow and return service valves are open, remove
appliance casing as described in 4.7.1, identify the automatic air
release valves (AAV) and loosen the dust cap/s by turning the
cap anti-clockwise one full turn. Ensure all manual air release
valves located on the heating system are closed. Connect the
fi lling loop as shown in fi g. 4, slowly proceed to fi ll the system
by fi rstly opening the inlet valve connected to the fl ow pipe, and
then turning the lever on the fi ll valve, to the open position. As
water enters the system the pressure gauge will begin to rise.
Once the gauge has reached 1 BAR close both valves and begin
venting all manual air release valves, starting at the lowest fi rst.
It may be necessary to go back and top-up the pressure until
the entire system has been fi lled. Inspect the system for water
tightness, rectifying any leaks.
5.4 INITIAL FLUSHING OF THE SYSTEM
The whole of the heating system must be fl ushed both cold
and hot as detailed in 5.8. Open all radiator or heating valves
and the appliance fl ow & return service valve. 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. Refi ll the boiler and heating system as described in 5.3.
5.5 PRE-OPERATION CHECKS
Before attempting the initial lighting of the appliance, the fol-
lowing 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, (see
7.8) particularly continuity, polarity and resistance to earth;

ensure the 3 AMP fuse – supplied with the appliance – has
been fi tted;

ensure the system has been fi lled, vented and the pressure
set to 1 BAR;

ensure the fl ue system has been fi tted properly and in ac-
cordance with the instructions;

ensure all appliance service valves are open.
5.6 INITIAL LIGHTING
Ensure the electrical supply to the appliance is switched on.
Ensure any external controls are switched to an ‘ON’ position
and are calling for heat. Move the selector switch to the ON
position, the appliance will now operate as described in 1.2.
Should the appliance fail to ignite, refer to 5.6 and/or section 7
(mode of operation, parameter setting & faultfi nding).
5.7 CHECKING GAS PRESSURE AND COMBUSTION
ANALYSIS
The appliance is factory set so should require no additional
adjustment once installed. However to satisfy the require-
ments of GSIUR 26/9 (I.S. 813 ROI), it will be necessary to
gas rate the appliance using the gas meter that serves the
appliance and carry out a combustion analysis check in accor-
dance with BS 7967 (UK) to ensure that correct combustion is
occurring, see fl ow chart on page 36.
Additionally, if the gas valve has been adjusted, replaced, or
the appliance has been converted for use with another gas
type, then it becomes necessary to carry out a combustion
analysis check to ensure that correct combustion is occurring.
If there are no means to carry out a combustion analysis
check, then it will not be possible to complete the commissio-
ning procedure.
Details on how to carry out the combustion analysis can be
found in section 7.
IMPORTANT
It’s imperative that a suffi cient dynamic – gas – pressure is
maintained at all times. Should the dynamic gas pressure fall
below an acceptable level, the appliance may malfunction or
sustain damage.
5.8 FINAL FLUSHING OF THE HEATING SYSTEM
The system shall be fl ushed in accordance with BS 7593 (I.S.
813 ROI). Should a cleanser be used, it must be suitable for
Aluminium heat exchangers. It shall be from a reputable manu-
facturer and shall be administered in strict accordance with the
manufacturers’ instructions and the DWTA code of practice.
NOTE
Chemicals used to cleanse the system and/or inhibit corrosion
must be pH neutral, i.e. they should ensure that the level of the
pH in the system water remains neutral. Premature failure of
certain components can occur if the level of pH in the system
water is out-with normal levels.
5.8.1 INHIBITORS
See Section 3 “General Requirements”.
5.9 SETTING THE FLOW OUTLET TEMPERATURE
The fl ow outlet temperature can be adjusted between 40 °C -
80 °C for standard CH system by using the Heating thermostat
knob (see fi g.1).
5.10 SETTING THE SYSTEM DESIGN PRESSURE
The design pressure should be a minimum of 0.5 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 appli-
ance (up to the maximum of 1.5 BAR total).
N.B.
The safety valve is set to lift at 3 BAR/30 metres/45 psig.
To lower the system pressure to the required value, drain off
some water from the appliance drain valve until the required
fi gure registers on the pressure gauge (see fi g. 1).
5.11 REGULATING THE CENTRAL HEATING SYSTEM
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 heads. Adjust
radiator return valves and any branch circuit return valves
until the individual return temperatures are correct and are
approximately equal.
5.12 FINAL CHECKS
• ENSURE ALL TEST NIPPLES ON THE APPLIANCE GAS
VALVE ARE TIGHT AND CHECKED FOR TIGHTNESS.
• ENSURE THE APPLIANCE FLUE SYSTEM IS FITTED
CORRECTLY AND IS PROPERLY SECURED.
• ENSURE ALL PIPE WORK IS RE-CHECKED FOR TIGHT-
NESS.
• RE-FIT APPLIANCE CASING.
• COMPLETE BENCHMARK CHECKLIST.
FOR UK ONLY
Complete details of the boiler, controls, installation and com-
missioning in the Benchmark checklist at the back of this
book. It is important that the Benchmark checklist is correctly
completed and handed to the user. Failure to install and com-
mission the appliance to the manufacturers instructions will
invalidate the warranty.
5.13 INSTRUCTING THE USER
Hand over all documentation supplied with this appliance –
including these instructions – and explain the importance of
SECTION 5 - COMMISSIONING