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507330-03G / 31-5000662
Issue 2209
Page 25 of 36
Figure 34. Heating Sequence of Operation
Demand
15
ON
OFF
CAI
35
1
Pre-Purge
Ignitor Warm-up
Blower
“On” Delay
Post
Purge
5 SEC
80
Ignitor
Gas Valve
Indoor Blower
39
Trial for
Ignition
Blower on time will be 45 seconds after gas valve is energized. Blower off time will depend on “OFF TIME” Setting.
Unit Start-Up
FOR YOUR SAFETY, READ BEFORE LIGHTING UNIT
Do not use this furnace if any part have been
underwater. Immediately call a licensed professional
service technician (or equivalent) to inspect the furnace
and to replace any part of the control system and any
gas control which has been underwater.
WARNING
If overheating occurs or if gas supply fails to shut off,
shut off the manual gas valve to the appliance before
shutting off electrical supply.
WARNING
Before attempting to perform any service or
maintenance, turn the electrical power to unit OFF at
disconnect switch.
CAUTION
BEFORE LIGHTING
smell all around the appliance area
for gas. Be sure to smell next to the floor because some
gas is heavier than air and will settle on the floor.
The gas valve on this unit will be equipped with a gas
control switch. Use only your hand to move the switch.
Never use tools. If the switch will not turn or if the control
switch will not move by hand, do not try to repair it.
Placing the Furnace into Operation
These units are equipped with an automatic ignition
system. Do not attempt to manually light burners on these
furnaces. Each time the thermostat calls for heat, the
burners will automatically light. The ignitor does not get hot
when there is no call for heat on units with an automatic
ignition system.
If you do not follow these instructions exactly, a fire
or explosion may result causing property damage,
personal injury or death.
WARNING
Gas Valve Operation
1.
STOP!
Read the safety information at the beginning
of this section.
2. Set the thermostat to the lowest setting.
3. Turn off all electrical power to the unit.
4. This furnace is equipped with an ignition device which
automatically lights the burners. Do not try to light the
burners by hand.
5. Remove the upper access panel.
6. Move switch on gas valve to OFF. Do not force. See
7.
Wait five minutes to clear out any gas. If you then
smell gas,
STOP!
Immediately call your gas supplier
from a neighbor’s phone. Follow the gas supplier’s
instructions. If you do not smell gas go to next step.
Figure 35.
Gas Valve Shown in
“ON”
Position
8. Move switch on gas valve to ON. Do not force. See
9. Replace the upper access panel.
10. Turn on all electrical power to the unit.