Shutting Down Your Furnace; Performing Routine Maintenance - Carrier 58MSA User Manual

8. Turn ON the electrical supply to the furnace and wait 1
minute. (See Fig. 13.)
9. Open the external manual gas valve. (See Fig. 14.)
10. Set the room thermostat to a temperature slightly
above the room temperature. This will automatically
signal the furnace to start.
11. When the furnace receives the start signal, the inducer is
started. When the pressure switch verifies that there is suf-
ficient combustion air, the control energizes the hot sur-
face ignitor. After the hot surface ignitor is heated for 17
sec, the gas valve permits gas to flow to the main burners.
After ignition and a time delay of approximately 60 sec,
the furnace blower starts.
NOTE:
If the burners fail to ignite after 4 attempts, the fur-
nace control system will lock out. If lockout occurs, main
burners fail to light, or blower does not come on, shut down
the furnace and call your dealer for service.
12. Set your thermostat to the temperature that satisfies
your comfort requirements. SUGGESTION: Setting
the thermostat back a few degrees—and compensating
for the difference with warmer clothing—can make a big
difference in your fuel consumption. The few degrees at
the top of your thermostat "comfort level'' are the most
costly degrees to obtain.
When room temperature drops below the temperature
selected on the thermostat, the furnace will be switched
on automatically. When the room temperature reaches
the temperature selected on the thermostat, the furnace
will be switched off automatically.
Some thermostats have a "FAN'' mode with 2 selections,
AUTO and ON. When set on AUTO, the furnace blower
cycles on and off. In ON mode, the furnace blower runs
continuously. Continuous-fan keeps the temperature lev-
el in your home more evenly balanced. It also permits the
indoor air to be continuously filtered.

SHUTTING DOWN YOUR FURNACE

Should you need to shut down your furnace for service or
maintenance, you will need to turn the furnace off. The fol-
lowing procedures must be followed:
1. Set your room thermostat to the lowest temperature
setting. (See Fig. 15.)
2. Close the external manual gas valve (See Fig. 7.)
3. Turn off electrical supply to the furnace. (See Fig. 16.)
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4. Remove main furnace door. (See Fig. 9.)
5. Turn the control switch on the gas valve to the OFF posi-
tion. (See Fig. 17.)
6. Replace the control access door. (See Fig. 14.)
7. If the furnace is being shut down because of a malfunc-
tion, call your dealer as soon as possible.
Furnace is not to be installed, operated, and then
turned off and left turned off in an unoccupied
structure during winter. (See Heading South for
the Winter? procedures in maintenance section).
Freeze damage to furnace could occur.
PERFORMING ROUTINE
MAINTENANCE
NOTE:
The qualified installer or agency must use only
factory-authorized replacement parts, kits, and accessories
when modifying this product.
Installing and servicing heating equipment can be hazard-
ous due to gas and electrical components. Only trained and
qualified personnel should install, repair, or service heating
equipment.
Untrained personnel can perform basic maintenance func-
tions such as cleaning and replacing air filters. All other
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CAUTION
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