Table of Contents
Advertisement
6 - Plug and check any unused drain pan openings for
tightness. Torque plugs to 30 in. lb. to prevent water
leaks or seepage from the drain pan.
7 - Install a 2" trap in the primary drain lines as close to
the unit as practical (see figure 18). Make sure the
top of the trap is below the connection to the drain
pan to allow complete drainage of the pan.
NOTE – Horizontal runs must have an anti-siphon air vent
(standpipe) installed ahead of the horizontal run. An ex-
tremely long horizontal run may require an oversized drain
line to eliminate air trapping.
NOTE – Do not operate air handler without a drain trap.
The condensate drain is on the negative pressure side of
the blower; therefore, air being pulled through the conden-
sate line will prevent positive drainage without a proper
trap.
8 - Route the drain line to the outside or to an
appropriate drain. Drain lines must be installed so
they do not block service access to the front of the
air handler. A 24" clearance is required for filter, coil,
or blower removal and service access.
NOTE – Check local codes before connecting the drain
line to an existing drainage system.
Insulate the drain lines where sweating could cause water
damage.
TEST CONDENSATE DRAIN
Test the drain pan and drain line after installation:
1 - Pour several quarts of water into drain pan, enough
to fill drain trap and line.
2 - Check to make sure the drain pan is draining
completely, no leaks are found in drain line fittings,
and water is draining from the end of the primary
drain line.
3 - Correct any leaks found.
BEST PRACTICES
The following best practices are recommended for the
condensate removal process:
• Main and overflow drain lines should NOT be smaller
than both drain connections at drain pan.
• Overflow drain line should run to an area where home-
owner will notice drainage.
• It is recommended that the overflow drain line be vented
and a trap installed. Refer to local codes.
• Condensate drain lines must be configured or provided
with a cleanout to permit the clearing of blockages and
for maintenance without requiring the drain line to be cut.
IMPORTANT
A field-fabricated secondary drain pan, with a drain pipe
to the outside of the building, is required in all installations
over a finished living space or in any area that may be
damaged by overflow from the main drain pan. In some
localities, local codes may require a secondary drain
pan for any horizontal installation.
DUCT SYSTEM
The air handler is provided with flanges for the connection
of the plenum and ducts. The air handler is equipped with
flanges that can form a filter rack for the installation of the
air filter, or the filter may be installed as part of the return
air duct system.
Supply and return duct system must be adequately sized
to meet the system's air requirements and static pressure
capabilities. The duct system should be insulated with a
minimum of 1" thick insulation with a vapor barrier in con-
ditioned areas or 2" minimum in unconditioned areas.
Supply plenum should be the same size as the flanged
opening provided around the blower outlet and should ex-
tend at least 3 ft. from the air handler before turning or
branching off plenum into duct runs. The plenum forms an
extension of the blower housing and minimizes air expan-
sion losses from the blower.
INSTALLING DUCT SYSTEM
Connect supply air duct to the flange on top of the air han-
dler. If an isolation connector is used, it must be nonflam-
mable.
A return air duct system is recommended. If the unit is
installed in a confined space or closet, a return connection
must be run, full size, to a location outside the closet.
CONNECTING REFRIGERANT LINES
Refrigerant lines must be connected by a qualified techni-
cian in accordance with established procedures.
Refrigerant lines must be clean, dehydrated, refrigerant-
grade copper lines. Air handler coils should be installed
only with specified line sizes for approved system
combinations.
Handle the refrigerant lines gently during the installation
process. Sharp bends or possible kinking in the lines will
cause a restriction.
Do not remove the caps from the lines or system
connection points until connections are ready to be
completed.
1 - Route the suction and liquid lines from the fittings on
the indoor coil to the fittings on the outdoor unit. Run
the lines in as direct a path as possible avoiding
unnecessary turns and bends.
2 - Make sure that the suction line is insulated over the
entire exposed length and that neither suction nor
liquid lines are in direct contact with floors, walls,
duct system, floor joists, or other piping.
3 - Connect the suction and liquid lines to the
evaporator coil.
4 - To avoid damaging the rubber grommets in the
cabinet while brazing, slide the rubber grommets
over the refrigerant lines until they are away from
the heat source.
5 - Braze using an alloy of silver or copper and
phosphorus with a melting point above 1,100°F
(593°C).
Page 21
IMPORTANT
Advertisement
Table of Contents
