Lennox SCA 010 Installation, Operation & Maintenance Manual page 112

PLANNED MAINTENANCE PLANNED MAINTENANCE PLANNED MAINTENANCE PLANNED MAINTENANCE PLANNED MAINTENANCE
Regular maintenance of your Rooftop will extend its
operating life and reduce operating faults. We recommend
that the unit is serviced by a trained refrigeration engineer.
A log book kept near the equipment detailing work carried
out, by whom and when, is an excellent diagnostic tool.
The panel opening key is required for this work (see
"TRANSPORT" page 3).
MOTOR-FAN ASSEMBLY
After 50 operating hours check the belt tension and the pulley
screws for tightness. Repeat this check every two months.
The fans contain bearings that are "lubricated for life", but
we recommend replacing them every 10,000 operating
hours.
During this inspection, check the condition of the anti-
vibration mounts, by looking for any cracks or signs of
abnormal wear.
FILTERS
The filters fitted as standard are manufactured with a
washable and recyclable material. The CLIMATIC indicates
if they are blocked. The cleaning schedule is directly related
to the environment in which the equipment is operated.
However, monthly cleaning is recommended. A blocked filter
will reduce the performance and reliability of the Rooftop.
After removing the filters, remove any dust and wash them
in a tepid water solution with a little liquid detergent. After
rinsing in fresh water, leave the filters to dry. Take all
necessary precautions during operation to avoid damaging
or piercing the media, as this would require the damaged
cell to be replaced.
NOTE : The equipment must never be operated with the
filters removed.
To avoid prolonged shutdown, always keep a spare filter
set.
BURNERS (LG_/LD_ UNITS)
1. Periodically examine burner flames for proper
appearance during the heating season.
2. Before each heating season examine the burners for
Air circulation
Pull to remove filters
Figure 92
any deposits or blockage which may have occurred.
3. Clean burners as follows:
a - Turn off both electrical power and gas supply to
unit.
b - Open access panel to burner compartment.
c - Remove burner retaining bracket and lift burners
from orifices.
d - Clean as necessary and replace burners. Refit
retaining brackets. Make sure that burner heads line
up correctly. Spark gap on ignition electrode must be
properly set. Refer to Heating Adjustment section. Re-
place access panel.
Restore electrical power and gas supply.
Follow lighting instructions attached to unit and use
inspection port in access panel to check flame.
COMBUSTION AIR FAN (LG/LD UNITS)
A combustion air fan proving switch checks combustion air
fan operation before allowing power to the gas controller.
Gas controller will not operate if blower is obstructed.
Under normal operating conditions, the combustion air fan
wheel should be checked and cleaned prior to the heating
season. However, it should be examined periodically during
the heating season to establish an ideal cleaning schedule.
With power supply disconnected, the condition of the blower
wheel can be determined by looking through the vent
opening.
Clean combustion air fan as follows :
1. Shut off power supply and gas to unit.
2. Disconnect pressure switch air tubing from combus-
tion air fan port.
3. Remove and retain screws securing combustion air fan
to flue box. Remove and retain two screws from bracket
supporting vent connector. See figure 81
Danger of explosion.
Can cause injury or death. Do not
overtighten main burner mounting
screws. Snug righten only.
HEAT EXCHANGER ASSEMBLY
Combustion air fan
Gas valve
Burner
IOM / Rooftop Smart and Linéa™ Range - Page 111
WARNING
Heat exchanger tube
Baffle
Flue box
Vent connector
Figure 93