Verine Cupello, Installation, User And Servicing Instructions, Page: 11 / 20

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with dirt, the gas supply to it, or the thermocouple needs replacement.
The gas valve is a non-serviceable item. If this needs replacement, remove the data badge
then the M5 securing screw holding the valve bracket in place; remove all pipe unions, and
the complete valve. Replacement must be original manufacturer’s parts. Re-assemble in
the reverse of removal. Ensure setting pressures are as stated in Appliance Data.
Remove the casing, internal firebox (as per servicing section), lint arrestor and pilot unit by
using a screwdriver to remove the retaining screws. Clean the pilot assembly with a soft
brush and blow through. Check the aeration holes are free of any dirt or lint. Clean
thoroughly internally, the connection can be removed from the base of the pilot unit using
two spanners to make cleaning easier. Do not damage or try to dismantle the pilot
injector.
The unit is factory set and the only check necessary is to ensure the spark gap is correct.
See specifications for gas setting.
NEVER MODIFY OR BEND THE THERMOCOUPLE TO MAKE THE PILOT STAY ALIGHT . If the
pilot will not stay lit there is a problem with dirt, the gas supply, or the thermocouple
needs replacement. Modifications are dangerous and can have a serious unseen effect on
safety and therefore MUST not be done. Replacements must be original manufacturer’s
parts. Re-assemble in the reverse of removal. Ensure setting pressures are as stated in
Section 2; Appliance Data.
Catalysts
It is recommended that the catalysts are inspected for signs of damage and dirt during
routine servicing procedures. The expected life of the catalysts is in excess of 11,000 hours
(10 years of normal use). After this time the catalyst should be replaced.
If there are any deposits of dirt or soot on the catalysts they should be cleaned with a soft
brush and a vacuum cleaner. If removed for cleaning ensure the seals are in good
condition before replacing the catalyst. New seals will usually be required.
The performance of the catalyst may be checked using a combustion gas analyser as
follows. Any analyser used should conform to BS7927 : 1998 + A1 : 1999.
Important: The temperature of the gas emitted by the catalytic converter is in excess of
350
o
C. Measuring gas of this temperature may damage some types of gas analysers. If in
doubt consult the equipment manufacturer.
Ignite the fire as per the operating instructions, and run at maximum setting for 15
minutes. Position gas sample probe directly over the catalyst via the outlet grille, on top of
the appliance. Record the carbon dioxide (CO2) concentration and then the carbon
monoxide (CO) concentration as displayed by the analyser - also noting the units in which
the values are expressed.
Most analysers display carbon dioxide (CO2) concentrations in percentage (%) terms and
carbon monoxide concentration in parts per million (ppm) terms.
In order to calculate the combustion ratio for the appliance (CO/CO2) it is first necessary
to express both gas concentrations in terms of percentage. To convert from parts per
million (ppm) to a percentage (%) divide the ppm figure by 10,000. Examples : 35ppm =
0.0035%, 15ppm = 0.0015%, 5ppm = 0.0005%.
Now divide the concentration of carbon monoxide (CO) expressed in percent by the
concentration of carbon dioxide (CO2) to obtain the appliance combustion ratio.
CO (%)CO2 (%) = ratio
The combustion ratio of the gasses emitted by the catalytic converter should not exceed
0.0015.
If replacing, firstly, remove the decorative fireframe. The catalysts are located on the top of
the internal firebox and can be removed be unscrewing the retaining nuts securing the
clamping plate. Remove the catalyst and its seal and discard. Refit a new catalyst and
seals in reverse order, ensure the catalysts and door have a good seal.