necessary adjustments to operate the blower at either the low- or
16
17
OP
E
N
18
NOTE: If the burners fail to ignite after 4 attempts, the furnace 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 temper- ature that satisfies your comfort requirements.
SUGGESTION: Setting the ther- mostat back a few degrees and compensating for the difference with warmer clothing can make a big difference in your fuel con- sumption. 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 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 thermostat is set to AUTO, the furnace blower cycles on and off. In ON mode, the furnace blower runs continu- ously. Continuous fan keeps the temperature level in your home more evenly balanced. It also per- mits the indoor air to be continu- ously filtered. Fan On Plus™
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 following procedures must be followed:
1.Set your room thermostat to the lowest temperature setting. (See Fig. 19.)
®
19
20
2.Close the external manual gas valve. (See Fig. 9.)
3.Turn off electrical supply to the furnace. (See Fig. 20.)
4.Remove main furnace door. (See Fig. 11.)
5.Turn switch on the gas valve to OFF position.
(See Fig. 21 or 22.)
For 352MAV and 355MAV
21
OFF | ON |
| or |
For 340MAV and 350MAV
22
6.Replace main furnace door. (See Fig. 16.)
7.If the furnace is being shut down because of a malfunction, call your dealer as soon as possible.
!CAUTION
Furnace is not to be installed, operated, and then turned off and left turned off in an unoc- cupied structure during winter. (See “Heading South for the Winter?” procedures in main- tenance section on page 9.) Freeze damage to furnace would occur.
PERFORMING
ROUTINE
MAINTENANCE
NOTE: The qualified installer or agency must use only factory- authorized replacement parts, kits, and accessories when modifying this product.
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