1083292-UIM-A-0114
22
Johnson Controls Unitary Products
The condensate will flow to the drain better if an open stand pipe is
installed in the drain line. See Figure 28.
If evaporator coil or humidifier drains are combined with the furnace
drain, then the open stand pipe could be raised higher, above the 5”
minimum.
Do not drain other devices (humidifier, evaporator coil, etc.) into the top
opening of the vent stand pipe. Instead, install a second tee in the
vented drain tube below the furnace drain tee and route additional
drainage through the new tee.
CONDENSATE DRAIN TERMINATION
A condensate sump pump MUST be used if required by local codes, or
if no indoor floor drain is available. The condensate sump pump must
be approved for use with acidic condensate.
FIGURE 28:
Typical Condensate Drain, Vertical Installation
To Open Or
Vented Drain
Tee
5” Min.
Open Stand Pipe
(Anti-siphon air vent)
A loop has been added to the pressure switch vacuum hose. How-
ever, ensure that all pressure switch hoses are routed such that
they prevent any condensate from entering the pressure switch.
It is possible for condensation to form inside the combustion air
(intake) pipe in the summer months if significant length of combus-
tion air pipe passes through conditioned space. This problem can
be averted by installing the supplied vent drain and drain hose
located in the loose parts bag. The intake drain hose is to be
installed by connecting it to the inlet pipe coupling and to the collec-
tor box as shown in Figures 29, 31, and 32. The drain hose must
not sag or droop after it is installed. If glue is used when connecting
the intake pipe to the intake coupling, the drain opening in the vent
drain must not be plugged. If the intake drain is used, the bird
screen cannot be installed. This is only approved for upflow and
horizontal applications when the intake pipe is located on the top of
the furnace. This is true for all long horizontal venting in any furnace
configuration. This will keep condensate from entering the furnace.
DO NOT terminate the condensate drain in a chimney, or where the
drain line may freeze. If the drain line will be exposed to tempera-
tures below freezing, adequate measures must be taken to prevent
the drain line from freezing. Failure to provide proper protection
from freezing can result in improper operation or damage to the
equipment and possible property damage. When exposed to tem-
peratures below freezing, use of a 3 to 6 watt per foot at 115 VAC,
40°F (4.4°C) self-regulating, shielded and waterproof heat tape is
recommended on the drain line outside the furnace.
DO NOT trap the drain line at any location. The furnace has a con-
densate drain trap built into the drain pan.
Liquid anti-freeze will cause damage to internal plastic parts of this
furnace. DO NOT attempt to winterize the furnace using liquid
anti-freeze.
NOTICE
