Pilot Assembly; Catalysts; Testing For Firebox Leakage; Cleaning - Lennox Hearth Products 055M Installation And Operation Instructions Manual

21.0 PILOT ASSEMBLY

WARNING
NO ADJUSTMENTS ARE TO BE MADE TO THE ODS
PILOT SYSTEM. TAMPERING WITH THIS SYSTEM
CAN BE EXTREMELY HAZARDOUS.
Remove the glass facia, glass panel and burner unit (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 origi-
nal manufacturers parts. Re-assemble in the reverse of removal.
Ensure setting pressures are as stated in Section 3; Appliance Data.
It is recommended that the catalysts are inspected for signs of damage
and dirt during routine servicing procedures. The expected life of the

22.0 CATALYSTS

WARNING
DO NOT BLOCK THE CATALYSTS OR THE
APPLIANCE OUTLET GRILLE. BLOCKAGE MAY
CAUSE HIGH CARBON MONOXIDE LEVELS AND/OR
BREAKAGE OF THE GLASS FACIA PANEL.
Figure 18
WARNING
DO NOT OPERATE THE APPLIANCE WITH THE
CATALYST UNITS REMOVED.
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 analyzer as follows. Important: The temperature of the gases
emitted by the catalytic converters is in excess of 700
of this temperature may damage some types of gas analyzers. If in
doubt consult the equipment manufacturer.
Turn on the fireplace as per the operating instructions, and run at
maximum setting for 15 minutes. Position gas sample probe directly
over a 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 analyzer - also noting the units
in which the values are expressed. Most analyzers 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 per-
centage. 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.
The combustion ratio of the gasses emitted by the catalytic convertor
should not exceed 0.0015. If replacing, firstly, remove the glass facia as
described in section 15.0. 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 catalysts and seals and
discard. Refit a new catalysts and seals in reverse order, ensure the
catalysts and door have good seals.
Appliances that are several years old or have been extensively disman-
tled should be checked for soundness. It is important that all the prod-
ucts of combustion pass through the catalytic converters at the top of
the firebox before leaving the appliance.
DO NOT BLOCK
The firebox is heated by lighting for a few minutes to provide a flow
through the firebox. The burner is then shut off and a smoke pellet or
THESE AREAS
match introduced at the base of the fire underneath the burner tray.
Large quantities of smoke will emerge from the top of the appliance, but
none should emerge from the joints or gasket faces, especially around
the door. It is important to note that the appliance can never be expect-
ed to be 100% smoke tight and small quantities of smoke may be seen
in corners of joints and gasket faces etc without affecting safety when
the fire is in operation.
GLASS PANEL -This can be cleaned with a suitable glass cleaner. The
following solutions are approved for use to clean glass.
Test on a small area first.
PAINTED AREAS - These can be cleaned using a dry cloth.
FINISHED METAL AREAS - These can either be cleaned using a
proprietary metal cleaner or baby oil. Test on a small hidden part before
cleaning. Always clean in the direction of the grain.
10
CO (%)
CO2 (%) = ratio

23.0 TESTING FOR FIREBOX LEAKAGE

24.0 CLEANING

WARNING
TURN OFF THE UNVENTED GAS ROOM HEATER
AND ALLOW TO COOL BEFORE CLEANING.
• Non-ammonia based household cleaner
• 50% -50% mix of white vinegar and water
• Gas fireplace/stove glass cleaner
F. Measuring gas
o