Carrier 59SU5A Manual page 31

59SU5A: Installation, Start-up, Operating and Service Maintenance Instructions
Any change in diameter to the pipe must be made as close to the furnace
as reasonably possible (see Fig.
The Maximum Vent Length for the vent and combustion air pipe (when
used) is determined from the Maximum Equivalent Vent Length
(Table 18) minus the number of fittings multiplied by the deduction for
each type of fitting used (Table
!
OPTIONAL CONFIGURATION FOR COMBUSTION
AIR INLET PIPE
In applications where there is a risk of excessive moisture entering the
combustion air inlet pipe, a moisture trap may be added to the inlet pipe
to help prevent moisture from entering the furnace from the combustion
air inlet pipe. (see Fig. 43).
When sizing venting systems, the equivalent length of the optional
moisture trap (15 feet/5 M) must be taken into account.
NOTE: Only connect combustion air inlet moisture drain downstream
of the furnace trap assembly as shown.
A A
TO CODE- - APPROVED DRAIN OR CONDENSATE PUMP
Recommend "T" fitting with 4--inch minimum height standpipe (A) of same diameter or larger extending upward.
Tee
Dry Well
Dry Well
Cap
(water tight
Cap and removable)
(water tight
and removable)
Representative drawing only, some models may vary in appearance.
Fig. 43 – Recommended Combustion Air Inlet Moisture Trap
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
45).
19).
NOTICE
A
Tee
Tee
Dry Well
and removable)
EXAMPLE FOR
UPFLOW INSTALLATIONS.
MAY BE APPLIED TO
OTHER CONFIGURATIONS.
Representative drawing only, some models may vary.
Fig. 44 – Sample Inlet Air Pipe Connection for Polypropylene
A200089
Fig. 45 – Combustion Air and Vent Pipe Diameter Transition
Recommended Combustion Air Inlet Moisture Trap
Recommended to prevent moisture from trickling into the furnace
vestibule, a trap can be installed in the intake air pipe near the furnace.
To prevent moisture, connecting a drain line to the trap is recommended
as trace amounts of moisture will evaporate into the intake air stream. If
the combustion air inlet is located near a moisture exhaust duct, or there
are other concerns of excessive moisture being drawn into the
combustion air inlet, it is encouraged to connect a drain line to the trap.
The trap can be constructed from a running tee of the same diameter of
the intake air pipe with EITHER a removable cap attached to a 6-inch
long pipe connected to the tee or the External Vent Trap Kit to help
prevent contaminants from entering the furnace (see
The External Vent Trap Kit accessory may be used as a trap for the
combustion air inlet pipe if a large amount of moisture must be removed.
The drain line may be connected to the same drain as the furnace
condensate and the evaporator coil condensate line ONLY if the inlet air
trap drain and the evaporator coil drain empty into an open segment of
pipe above the drain. The drain line must be connected downstream of
Cap
the condensate trap float switch (see
(water tight
Vent Trap Kit, refer to those instructions for proper drain connections.
A170122a
The tee may also be connected to the intake air pipe on the side of the
casing (see Fig. 43).
In any configuration, it will be necessary to add the equivalent length of
the tee (15 feet/5 M) to the Total Equivalent Vent Length of the venting
system.
31
Venting Systems
FURNACE
NOT IN
PIPE DIAMENTER
HORIZONTAL
TRANSITION IN
SECTION
SECTION
Location and Elbow Configuration
Fig. 11). When using the External
A12220
A93034
Fig. 43).