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IMPORTANT:
Never use the heater as a support for
ladders or other access equipment. Always test for
gas soundness with a suitable detection fluid after
completing any servicing or exchange of gas carrying
component. On completion of any service/fault find-
ing tasks which require the breaking and remaking of
electrical connections then the checks:- A:Earth
Continuity, B:Polarity and C:Resistance to Earth must
be repeated.
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Carry out the following procedure annually. The pre-
ferred time would be immediately before the winter
heating period. If very dirty conditions arise it may be
necessary to carry out this procedure more often. If the
unit takes in air through an air duct or filter assembly,
more frequent service may be necessary.
9.1.1
Isolate the heater from the gas and electricity supply
by shutting off the appliance cock and disconnecting
the union connector, switching off the local electrical
supply and removing the appliance plug.
9.1.2
Remove the fan plug from the burner. Unscrew the
securing screws on the burner flange. The burner can
now be removed. Unscrew the securing screw on the
fan flange spigot. The fan can now be removed.
9.1.3
Remove the fan and burner independently to floor
level and clean both items internally using a soft
brush and compressed air if available. Take care not
to damage the internal parts of the burner. Check fan
impeller for cleanliness and that free rotation is avail-
able. When removing burner take care not to disturb
the gasket on the flanged burner tube.
9.1.4
The electrodes are an integral part of the Burner
Head. To check spark gap remove the securing screws
on the electrode and withdraw it ensuring the gasket
is not damaged. Spark gap on electrode should be
approximately 3 mm.
9.1.5
With burner and fan removed, clean the outer sur-
faces of the tubes using a brush and wipe the inner
surface of the reflector with a soft damp cloth - use a
household detergent if necessary. Never use abrasive
cleaners on the the reflectors.
9.1.6
Re-assemble the burner and fan in reverse order.
Carry out the Testing Procedure 8.2.
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First isolate the heater from the gas and electricity
supply; shut off the appliance cock, disconnect the
gas union connection; switch off the local electrical
supply and remove the appliance plug.
Entry to the burner assembly is gained by removing
the two (2) door screws and opening the hinged side
cover. Entry to the combustion chamber is gained by
removing the combustion chamber cover (7 screws).
9.2.1
Electrode (see section 9.1.4)
9.2.2
Burner Head/Injector Jet
When the cover is removed completely, the burner
assembly is exposed. Unscrew the burner cup.
Remove brass injector jet (orifice). Replace in reverse
sequence.
9.2.3
Solenoid Valve/Governor
Remove burner head as 9.2.2. Unscrew 4 mm slotted
screws on top of burner securing the solenoid/gover-
nor body. Withdraw the four wires tagged to the sole-
noid (TEKNIGAS), or the four wires between the
solenoids (SIT). The solenoid/governor and fittings can
now be withdrawn from the compartment.
The solenoid(s) can be removed from the body by
extracting the circlip and sliding (TEKNIGAS), unscrew-
ing central screw (SIT). Replace in reverse sequence.
Note: Earth is green/yellow.
9.2.4
Automatic Flame Control Unit
Remove grey ignition lead. Withdraw the 10 point edge
connector. Unscrew four (4) screws from the cover.
Replace if faulty. Refit in reverse sequence.
9.2.5
Pressure Switch
Disconnect the two (2) rubber tubes. Remove wires
from the three blades. Remove two (2) screws which
secure the pressure switch to the burner. Remove
pressure switch.
Replace pressure switch if faulty and refit in reverse
sequence ensuring that the rubber tubes are recon-
nected to the switch correctly.
Note:
Wires fitted as follows:
NO - Yellow
NC - White
Common - Black
9.2.6
Neons
Remove the two push on connectors and remove the
neons by pushing downwards. Replace in reverse
sequence.
9.2.7
Fuse
Pull out drawer containing fuse in the panel mounted
mains socket.
