Carrier 58MTA Installation, Start-Up, And Operating Instructions Manual page 33

Fig. 43_Rooftop Termination (Dimension "A" is Touching or 2-in. Maximum Separation)
A96128
Unit must not be installed, operated, and then turned off and
left in an unoccupied structure during cold weather when
temperatule drops to 32°F and below unless drain trap and
drain line have adequate freeze protection. See Service and
Maintenance Instructions for winterizing procedure.
GENERAL
Condensate trap is shipped installed in the blower shelf and factory,
connected for UPFLOW applications. Condensate trap must be
RELOCATED for use in DOWNFLOW and HORIZONTAL
applications.
Condensate trap MUST be used for all applications.
An external trap is not required when connecting the field drain to
this condensate trap.
The field drain connection (condensate trap or drain tube coupling)
is sized for 1/2-in. CPVC, I/2-in. PVC. or 5/8-in. ID tube
connection.
Drain pipe and fittings must conform to ANSI standards and
ASTM D1785, D2466 or D2846. CPVC or PVC cement must
conform to ASTM D2564 or F493. Primer must conform to ASTM
F656. In Canada, use CSA or ULC certified schedule 40 CPVC or
PVC drain pipe, fittings, and cement.
When a condensate pump is required, select a pump which is
approved for condensing furnace applications. To avoid conden-
sate spillage, select a pump with an overflow switch.
Furnace condensate is mildly acidic, typically in the pH range of
3.2 to 4.5. Due to corrosive nature of this condensate, a condensate
pH neutralizing filter may be desired. Check with local authorities
to determine if a pH neutralizer is required.
APPLICATION
The furnace, A/C, and humidifier drains may be combined and
drained together. The A/C drain must have an external, field-
supplied trap prior to the furnace drain connection. All drain
connections (furnace, A/C, or humidifier} must be terminated into
an open or vented drain as close to the respective equipment a_
possible to prevent siphoning of the equipment's drain.
See Fig. 48 for example of possible field drain attachment using
I/2-in. CPVC or PVC tee for vent and A/C or humidifier drain
connection.
Outdoor draining of the furnace is permissible if allowed by local
codes. Caution should be taken when freezing ambient may freeze
drain pipe and prohibit draining.
COMBUSTION
AIR
A93056
Fig. 44--Concentric Vent and Combustion-Air Roof
Termination (Dimension "A" is Touching or 2-in.
Maximum Separation)
J
F_ MAXIMUM
COMBUSTION AIR
VENT
A93057
Fig. 45--Concentric Vent and Combustion-Air Side
Termination (Dimension "A" is Touching or 2-in,
Maximum Separation)
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