![background image](http://html.mh-extra.com/html/carrier/986tc/986tc_installation-start-up-operating-and-service-and-maintenance-instructions_2562914017.webp)
17
CONDENSATE DRAIN CONNECTION
FROZEN AND BURST WATER PIPE HAZARD
Failure to protect against the risk of freezing may result in
property damage.
Special precautions MUST be made if installing furnace in an
area which may drop below freezing. This can cause improper
operation or damage to equipment. If furnace environment
has the potential of freezing, the drain trap and drain line must
be protected. The use of accessory drain trap heaters, electric
heat tape and/or RV antifreeze is required for these
installations.
CAUTION
!
PROPERTY DAMAGE HAZARD
Failure to follow this caution may result in burst water pipes
and/or property damage.
If a condensate pump is installed, a plugged condensate drain
or a failed pump may cause the furnace to shut down. Do not
leave the home unattended during freezing weather without
turning off water supply and draining water pipes or otherwise
protecting against the risk of frozen pipes.
CAUTION
!
DO NOT trap the drain line in any other location than at the
condensate drain trap supplied with the furnace. If possible, DO
NOT route the drain line where it may freeze. The drain line must
terminate at an inside drain to prevent freezing of the condensate
and possible property damage.
Special precautions MUST be made if installing furnace in an area
which may drop below 32
_
F (0
_
C). This can cause improper
operation or damage to the equipment. If the furnace environment
has the potential of freezing, the drain trap and drain line must be
protected. In areas where the temperature may be below 32
_
F (0
_
C), a Condensate Freeze Protection kit is required.
The kit
includes a condensate trap with heat pad and replaces the
factory--installed condensate trap. Refer to the Accessory section
of the Product Data for current kit number. A self--regulating,
shielded and waterproof heat tape rated at 3 to 6 watt per foot (10
to 20 watt per meter) at 115 volt, 40
_
F (4
_
C) may be used to
provide freeze protection of the remaining condensate drain line.
Wrap the drain trap and drain line with the heat tape and secure
with appropriate plastic ties. Follow the heat tape manufacturer’s
recommendations. Prime the trap before furnace operation.
The condensate drain line must be supported and/or secured per
local codes. Supports and clamps should be spaced to prevent the
drain line from sagging or being dislocated from the furnace or
termination point. In the absence of local codes, consult the current
edition of the National Standard Plumbing Code, in the U.S. or the
current edition of National Plumbing Code of Canada in Canada.
Upflow/Downflow Orientation
In the Upflow or Downflow orientation, the condensate trap is
inside the furnace casing. The condensate drain must be routed
from the trap through the furnace casing. The condensate drain can
be routed through the left or right side of the casing. (The left or
right side is as you are viewing/facing the furnace from the front.)
An indoor coil condensate drain or humidifier drain can be
connected to the external furnace condensate drain provided:
a. The drains are not hard piped together, and
b. There is an air gap at the point where the two drain lines
meet or
c. All condensate piping is at least 3/4-in. PVC and there is
a relief tee at the top of condensate drain piping as shown
below:
NOTE
: On narrower casings, it may be easier to remove the
condensate trap, connect the drain line components and re-install
the condensate trap. Read the steps thoroughly to familiarize
yourself with the required steps.
For Right Side Condensate Drain:
1. Remove the 7/8--in. knock--out from the right side of the
casing. See Fig. 16 for suggested knockout removal tech-
nique.
2. Remove the pre--formed rubber drain elbow and two spring
clamps from the loose parts bag.
3. Slide a spring clamp 1--inch (25 mm) down the plain end
(the end without the formed grommet) of the drain elbow.
4. From inside the casing, insert the formed grommet end of
the elbow through the 7/8--in. knockout in the casing.
5. Pull the grommet through the casing from the outside until
it is seated in the knockout
6. Attach the plain end of the drain elbow to the outlet stub on
the drain trap. Secure the drain elbow to the trap with the
spring clamp.
The remaining drain line can be constructed from field supplied
1/2--in. CPVC or 3/4--in. PVC pipe, in compliance with local
building codes. A factory--supplied 1/2--in. CPVC to 3/4--in. PVC
adapter is supplied in the loose parts bag for use as required.
7. Install the adapter or connect the 1/2--in. CPVC pipe by
sliding a spring clamp over the open end of the grommet on
the outside the furnace casing.
8. Open the spring clamp and insert the long end of the
adapter or the 1/2--in. CPVC pipe into the outlet stub on the
drain tube.
9. Connect additional condensate piping to a code--approved
drain, or to a condensate pump approved for use with acidic
furnace condensate and compatible with mineral and
vegetable oils, such as canola oil.
Allow at least 1/4-in. per foot (20 mm per meter) of slope down
and away from the furnace in horizontal sections of drain line.
TIP FROM CONTRACTORS
: Contractors have found that
temporarily removing the inducer assembly in upflow applications
while performing the steps, below, makes upflow left--side drain
connections easier.
For Left Side Condensate Drain Connection:
1. For left side condensate drainage, the drain line is routed
from the condensate trap, behind the inducer (upflow) or
gas valve (downflow) and out through the left side of the
furnace casing. A pre-formed 1/2--in. CPVC “Z-pipe” is
provided with the furnace. The Z-pipe is long enough to
extend across the casing for drain connections.
2. Locate the Z-pipe. Remove the pre-formed drain elbow and
four spring clamps from the loose parts bag.
3. The Z-pipe is connected to the condensate trap and the
outside of the furnace by modifying the formed rubber
drain elbow as shown in Fig. 13.
4. Remove the formed grommet from the rubber drain elbow
by cutting the elbow along the vertical line located about
1--3/8 in. (35 mm) away from the formed grommet. See Fig.
13.
DO NOT DISCARD THE FORMED GROMMET
OR THE RUBBER ELBOW
. Both of these pieces will be
used.
Assemble and route the drain line to the opposite side of the
furnace as detailed below:
5. Remove the knock-out from the left side of the casing. See
Fig. 16 for suggested knockout removal technique.