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4000124050-2
Diagram 14.1
9718
A
Bypass
The boiler
has a built-in bypass,
refer to diagram 14.1.
The boiler is supplied with the bypass open half a turn. It should
not be necessary to adjust the bypass, but if required ensure
that under no circumstances does the flow rate fall below the
figures specified,
refer to table 1. in section 3
(turn clockwise
'A' to close the valve ).
F24E shown
12 Commissioning
Should it be necessary to change the gas type, a conversion kit
with instructions will be required.
This modification must only be carried out by a competent
person.
Conversion natural gas (G20) to G30/G31 Part No. A20027.
Setting the step pressure.
Adjusting the step pressure may be a necessary operation after
gas conversion or after changing the gas control valve when a
new replacement part is required.
Proceed as follows:
• Gain access to the gas control valve, connect a pressure
gauge.
13 Changing Gas Type
When all adjustments are completed.
• Adjust heating temperature to maximum.
• Check that any external controls, if fitted, are calling for heat
(set room thermostat to maximum).
• Allow the temperature to rise to the maximum value, with all
radiator valves open. The temperature rise will cause release of
the air contained in the water of the central heating system.
• Air driven towards the boiler will be automatically released
through the automatic air vent.
• The air trapped at the highest point of the system must be
released by bleeding the radiators. Check the burner gas rate
required, ten minutes after lighting. Refer to Data Label on
electrical controls box. Should there be any doubt about the
gas rate it should be checked at the meter, refer to technical
data.
On reaching maximum temperature, the boiler should be
turned off and the system drained as rapidly as possible whilst
still hot.
• Refill system to a pressure of between 1 and 2 bar and vent
as before.
• Restart boiler and operate until a maximum temperature is
reached. If necessary, refer to section 14 to adjust the bypass.
Shut down boiler and vent heating system. If necessary, top up
heating system and make sure that a pressure of at least 1 bar
is indicated when system is COLD.
F24E Only
Flush the domestic hot water system by opening the
hot water taps for several minutes.
Completion
Adjust the boiler temperature control and any system controls
to their required settings.
For IE, it is necessary to complete a "Declaration of Conformity"
to indicate compliance to I.S.813. An example of this is given
in the current edition of I.S.813.
• Unclip the control box,
see diagram 11.1.
• Run the appliance in heating mode.
• Read the burner pressure setting in heating mode, before the
boiler modulates.
• Adjust the central heating output to the minimum setting by
adjusting potentiometer
P3
,
refer to commissioning section.
• Adjust the potentiometer
P6
burner pressure to the desired
value, by inserting a small flat edge screw driver into the
arrowed slot, turn to adjust to the desired setting,
see diagram
12.2.
• Return the potentiometer
P3
to its initial value.
Please ensure the “Benchmark” logbook is completed and left
with the user and the magnetic lighting instruction label is
placed on the surface of the boiler casing.
Instruct the User
Instruct and demonstrate the lighting procedure and advise the
user on the safe and efficient operation of the boiler.
Instruct on and demonstrate the operation of any heating
system controls.
Advise the user on the use and maintenance of any scale
reducer and pass on any relevant instructional documents.
Advise that to ensure the continued efficient and safe operation
of the boiler it is recommended that it is checked and serviced
at regular intervals. The frequency of servicing will depend
upon the installation conditions and usage, but in general, once
a year should be enough.
Draw attention, if applicable, to the current issue of the Gas
Safety (Installation and Use) Regulations, Section 35, which
imposes a duty of care on all persons who let out any property
containing a gas appliance in the UK.
It is the Law that any servicing is carried out by a competent
person.
Advise the user of the precautions necessary to prevent
damage to the system, boiler and the building, in the event of
the heating system being out of use during frost or freezing
conditions.
Advise the user that the permanent mains electrical supply
SHOULD NOT be switched off, as the built in frost protection
and pump saver program would not be operable.
Reminder, leave these instructions and the ‘Benchmark’ logbook
with the user.
14 Bypass Setting
