5
The vent system must slope toward the furnace for drain-
age of condensate. Provision must be made to drain the
condensate and protect the condensate drain trap and
drain line from freezing conditions.
WARNING
To prevent possible death or personal injury
due to asphyxiation, common venting with
other induced draft appliances is not
allowed. Carefully read and follow all
instructions given in this section.
NOTE: The louvers in the furnace door and top must never
be obstructed. They must remain open so air can flow
through the furnace and cool internal components.
INDOOR HUMIDITY
Relative humidity is the amount of water vapor in the air
relative to the amount the air can hold at the same tempera-
ture. Example: At 40% relative humidity, the air could hold
2 1/2 times as much moisture (2.5 x 40 = 100%) before
becoming saturated.
The colder the air; the less moisture it can hold. As air is
warmed, its ability to hold moisture is increased.
Example: A winter day, outdoor temperature 10°F, and
relative humidity of 70%. If that air enters a home and is
warmed to 72°F the relative humidity will drop to 6% (very
dry) if no more moisture is added.
Relative humidity is important to your health and home as
proper humidification helps reduce respiratory difficulties
and helps improve the indoor air quality.
A good relative humidity is one just high enough to barely
start condensation along the lower edges or lower corners
of the windows. More than that can be damaging.
Frequent fogging or excessive condensation on inside
windows indicates the indoor humidity level is too high for
outdoor weather conditions. Damage to the building may
result if the condition persists. (Condensation on inside of
storm windows indicates loose inside windows. Adding
weather-stripping to tighten inside windows usually cor-
rects this problem.)
The following table shows the recommended maximum
indoor humidity in relationship to the outdoor temperatures.
Temperature
(° F.)
Humidity
+20°
35%
+10°
30%
0°
25%
-10°
20%
-20°
15%
Table 1
PROPANE FURNACES ONLY
WARNING
To avoid death, personal injury or property
damage due to explosion or fire, install a
gas detecting warning device. Since the
odorant in propane gas can be reduced by
iron oxide (rust), a gas detecting warning
device is the only reliable method to detect
propane gas leaks.
WARNING
If the gas furnace is installed in a basement,
an excavated area or a confined space, it is
strongly recommended to contact a propane
supplier to install a gas detecting warning
device in case of a gas leak.
•
Since propane gas is heavier than air,
any leaking gas can settle in any low
areas or confined spaces.
•
Propane gas odorant may fade, making
the gas undetectable except with a
warning device.
An undetected gas leak will create a danger
of explosion or fire. If the presence of gas is
suspected, follow the instructions on the
cover of this manual. Failure to do so could
result in SERIOUS PERSONAL INJURY OR
DEATH.
II. Operation
THERMOSTAT
There are many types and styles of thermostats but the
operation is usually similar. BE SURE TO BECOME FA-
MILIAR WITH YOUR THERMOSTAT. The simplest type of
thermostat only starts and stops the furnace to maintain the
proper room temperature. The most widely used types will
control both heating and cooling functions and will have a
Fan Switch with Auto and ON settings. On Auto, the
circulating air blower will cycle on/off with the furnace but if
switched to ON it will run constantly whether or not the
furnace is on.
In addition there are thermostats that automatically switch
from Heating to Cooling and with night setbacks. The night
set-back, or multiple set-back type, will lower the tempera-
ture at night or during the day when no one is at home.
