Section Vi: Condensate Piping And Furnace Venting Configuration; Typical Condensate Drain, Vertical Installation - Johnson Controls YP9C Series Installation Manual

Twinning
These furnaces are not to be twinned. If more than one furnace is
needed in an application, each furnace must have its own complete
duct system and its own wall thermostat.
Section VI: Condensate piping and
furnace venting configuration
Condensate drain location
As shipped from the factory:
• For all 60k and 80k input furnaces the main drain is plumbed
through the casing right-side opening when viewed from the front
of the furnace.
• For all 100k and 120k input furnaces the main drain is plumbed
through the casing left-side opening when viewed from the front
of the furnace.
The Figures 25-29 show the condensate drain arrangement for the var-
ious possible furnace and vent blower positions.
The condensate hoses must slope downwards at all points.
The condensate water will flow to the drain better if an open tee, or
short length of pipe is installed in the drain line.
CAUTION
!
The furnace condensate pan is self priming and contains an
internal trap to prevent flue gas leaking. Do not install an exter-
nal condensate trap.
When drain hose routing changes are required (shown in Figures 25-
29), be sure to cap all unused openings.
If rerouting hoses - excess length should be cut off so that no sagging
loops will collect and hold condensate - which will cause the furnace to
not operate.
No hose clamps are needed for connecting the condensate pan.
Important: The furnace, evaporator coil, and humidifier drains
may be combined and drained together. The evaporator coil
drain may have an external, field-supplied trap prior to the fur-
nace drain connection to prevent conditioned air leakage. All
drain connections (furnace, evaporator coil, or humidifier) must
be terminated into an open or vented drain as close to the
respective equipment as possible. Regular maintenance is
required on condensate drainage system.
Important: Condensate must be disposed of properly. Follow
local plumbing or wastewater codes. The drain line must main-
tain a 1/4 in. per foot (21 mm/m) downward slope to the drain.
Important: If an external vent tee is being installed, then it must
have its own condensate trap before it is disposed into an open
or vented drain. This is not to be considered as a second trap as
referenced elsewhere in this document.
The condensate will flow to the drain better if an open stand pipe is
installed in the drain line. See Figure 24.
If evaporator coil or humidifier drains are combined with the furnace
drain, then the open stand pipe could be raised higher, above the 5 in.
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.
NOTICE
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.
Johnson Controls Ducted Systems
CAUTION
!
It is possible for condensation to form inside the combustion air
(intake) pipe in the summer months if significant length of combustion
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 con-
necting it to the inlet pipe coupling and to the collector box as shown
in Figures 25 - 28. 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 hori-
zontal venting in any furnace configuration. This will keep condensate
from entering the furnace.
Figure 24: Typical condensate drain, vertical installation
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.
WARNING
!
DO NOT terminate the condensate drain in a chimney, or where the
drain line may freeze. If the drain line will be exposed to temperatures
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 temperatures
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.
WARNING
!
Liquid anti-freeze will cause damage to internal plastic parts of this
furnace. DO NOT attempt to winterize the furnace using liquid
anti-freeze.
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