29
Check Limit and Fan Control
WARNING
To avoid premature failure of heat ex-
changer or possible property damage,
injury or fire, do not change the limit
control, which is factory preset.
Check limit control operation after 15 minutes of opera-
tion by blocking the return air grille(s).
1. After several minutes the main burners must go
OFF. Blower will continue to run.
2. Remove air restrictions and main burners will re-
light after a few minutes.
To Turn Furnace Off
Adjust the thermostat setting below room temperature.
1. Main burners must go off
2. Circulating Air Blower will continue to run for 60, 90,
120 or 180 seconds.
3. Set the thermostat to lowest setting.
4. Turn off the electrical power supply to the furnace.
5. Remove the louvered door on the front of the fur-
nace by turning the latch screws 1/4 turn each.
6.
White Rodgers Model 36E36 or 36E37 or Honeywell
Model VR-8205 (Figures 28 and 27):
Turn the gas
control knob clockwise
to the OFF position for
either the White Rodgers gas valve or the Honeywell
gas valve.
White Rodgers Model 36E22 or 36E23 (Figure 29):
Push the selector switch to "OFF".
7. Close manual gas shut-off valve external to the
furnace.
8. Replace the door on the furnace.
XIII. Maintenance
WARNING
To avoid electrical shock, injury or death,
disconnect electrical power before per-
forming any maintenance.
CAUTION
If you must handle the ignitor, handle
with care. Touching the ignitor body with
bare fingers, rough handling, or vibra-
tion could result in early ignitor failure.
Only a qualified servicer should ever
handle the ignitor.
Have the furnace checked at least once every year,
before the heating season begins, to be sure that there
is adequate combustion air and that the vent system is
working properly.
Have vent pipe checked to be sure it is not blocked by
debris, which could permit fumes to enter the house.
Replace any leaking sections of vent pipe.
For a GUD two pipe installation, inspect the combustion
air inlet screen for blockage. Clean screen when needed.
Air Filter
WARNING
Never operate furnace without a filter
installed as dust and lint will build up on
internal parts resulting in loss of effi-
ciency, equipment damage and possible
fire.
See the Specification Sheet for filter sizes.
This furnace is equipped with a permanent type wash-
able high velocity filter(s). Filter(s) should be inspected
and cleaned every two months or as required. If the
replacement of the filter(s) becomes necessary, it must
be replaced with a filter(s) of the same type and size.
Remember that dirty filters are the most common cause
of inadequate heating or cooling performance.
WARNING
Disconnect the electrical power to the
furnace before removing the filter or per-
forming any other maintenance.
To remove the filter, turn the latches on lower door.
Remove the door. The blower motor will automatically
stop through the interlock switch.
