8
III. Maintenance
AT LEAST ONCE A YEAR, BEFORE THE HEATING SEA-
SON BEGINS, have the furnace checked by a qualified
servicer to be certain there is adequate combustion air and
that the furnace and the vent system are working properly.
Have the vent pipe and combustion air pipe (some models)
checked for blockage by debris or leaks, which could permit
fumes to enter the house. Replace any damaged sections of
the vent pipe.
WARNING
PERSONAL INJURY HAZARD
To avoid death or personal injury due to
electrical shock, disconnect the electrical
power before performing any maintenance.
Replacing or Cleaning Filters
WARNING
PERSONAL INJURY HAZARD
To avoid death, personal injury or property
damage, never operate furnace without a
filter installed. Dust and lint will build up on
internal parts resulting in loss of efficiency,
equipment damage and possible fire.
If filter replacement becomes necessary, it must be replaced
with a filter of the same type and size that complies with
UL900 or CAN/ULC-S111 standards.
See the Specification Sheet for filter sizes.
WARNING
PERSONAL INJURY HAZARD
To avoid death or personal injury due to
electrical shock, disconnect the electrical
power before removing filters or performing
any maintenance.
The filter is designed for high velocity heating and cooling
applications. Filters must be inspected, cleaned or changed
every two months or as required. It is the owner's responsi-
bility to keep air filters clean. NOTE: Dirty filters are the most
common cause of inadequate heating or cooling perfor-
mance.
To remove the filter contained in the furnace retaining rails,
disconnect electrical power to the furnace and remove the
lower door by turning the door latches 1/4 turn.
Grasp the lower portion of the filter, lift up to disengage it from
the lower railing, move towards blower, drop filter down. Pull
filter outward. (Figure 8)
Turning Off Furnace
1. Set the thermostat to lowest setting.
2. Turn off the electrical power supply to the furnace.
3. Remove the upper door on the front of the furnace by
turning the latch screws 1/4 turn each.
4. Turn the gas control knob clockwise
to the "OFF"
position or either the White Rodgers 36-E gas valve
(Figure 3) or the Honeywell VR-8205 gas valve (Figure
4). For the Robertshaw 7222 gas valve (Figure 5) slide
the lever to the "OFF" position. Do not use excessive
force.
5. Close manual gas shut-off valve external to the furnace.
6. Replace the door on the furnace.
Electronic Control Module
The furnace is equipped with a self-diagnostic electronic
control module. If a furnace component is not operating
properly, the control module will repeatedly flash a red light on
and off in a factory-programmed sequence, depending on the
problem encountered.
If a furnace equipped with a self diagnostic module is not
operating properly, look through the observation window in
the blower access door and make note of the number of
flashes in the sequence. Contact a qualified servicer for
further information. Do not attempt to troubleshoot the prob-
lem yourself.
Reset After Control Lock-Out
If ignition has not been achieved for any reason after three
ignition cycles, the electronic control module will lock-out the
furnace. Ignition is no longer attempted. A lock-out causes
both the air blower and the vent blower to run continuously,
and ignition is no longer attempted. The control's diagnostic
light will then repeatedly flash once and then pause. When
this occurs, it may be necessary to reset the control by turning
the thermostat setting below room temperature for thirty
seconds and then returning the setting to the desired tem-
perature. The control may also be reset after a lock-out by
turning off the electrical disconnect switch to the furnace for
thirty seconds.
IMPORTANT: If the furnace must be reset frequently to
obtain satisfactory operation, a problem exists with your
furnace that must be corrected. Contact a qualified servicer..
