Carrier 59CU5A Installation, Start-Up, Operating And Service And Maintenance Instructions Download

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59CU5A: Installation, Start-up, Operating and Service and Maintenance Instructions

Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.

American Society of Heating, Refrigerating and Air Conditioning

Engineers (ASHRAE) or consult The Air Systems Design Guidelines

reference tables available from your local distributor. The duct system

should be sized to handle the required system design CFM at the design

external static pressure. The furnace airflow rates are provided, see

Table 11

- CFM (with Filter). When a furnace is installed so that the

supply ducts carry air circulated by the furnace to areas outside the space

containing the furnace, the return air shall also be handled by duct(s)

sealed to the furnace casing and terminating outside the space containing

the furnace.
Secure ductwork with proper fasteners for type of ductwork used. Seal

supply- and return-duct connections to furnace with code approved tape

or duct sealer.

NOTE:

Flexible connections should be used between ductwork and

furnace to prevent transmission of vibration.
Ductwork passing through unconditioned space should be insulated to

enhance system performance. When air conditioning is used, a vapor

barrier is recommended.
Maintain a 1-in. (25 mm) clearance from combustible materials to

supply air ductwork for a distance of 36-in. (914 mm) horizontally from

the furnace. See NFPA 90B or local code for further requirements.

Return Duct Sizing

Refer to the Filter Selection and Duct Sizing section for information on

the proper selection of filter sizes and the associated ductwork and duct

transitions. Improperly designed filtering systems and return ductwork

are the most common causes of airflow and/or noise complaints in

HVAC systems.

Ductwork Acoustical Treatment

NOTE:

Metal duct systems that do not have a 90 degree elbow and 10

ft. (3 M) of main duct to the first branch take-off may require internal

acoustical lining. As an alternative, fibrous ductwork may be used if

constructed and installed in accordance with the latest edition of

SMACNA construction standard on fibrous glass ducts. Both acoustical

lining and fibrous ductwork shall comply with NFPA 90B as tested by

UL Standard 181 for Class 1 Rigid air ducts.

NOTE:

For horizontal applications, the top most flange may be bent

past 90° to allow the evaporator coil to hang on the flange temporarily

while the remaining attachment and sealing of the coil are performed.

Table 7 – Air Filter Selection and Duct Sizing - In. (mm)

* Recommended to maintain air filter face velocity. See Specification Product Data for part

number.

Table 8 – Opening Dimensions - In. (mm)

Table 9 – Filter Media Pressure Drop (Clean) Versus Airflow - In. W.C. (Pa)

If the filter size that you are looking for is not contained in

Table 9

, see

Table 10

for a comparison of Pressure Drop (initial/clean resistance to airflow)

versus Face Velocity for a variety of filter media types.
The following equations relate Face Velocity (FPM), Filter Area and Airflow (CFM):
Filter Face Velocity = Airflow / Filter Area
Minimum Filter Area = Rated System Airflow / Maximum Filter Face Velocity

NOTICE

Cabinet air leakage is less than 2% at 1.0 in. w.c. Cabinet air leakage is

less than 1.4% at 0.5 in. w.c. when tested in accordance with ASHRAE

Standard 193.

FURNACE

CASING WIDTH

FILTER SIZE

FILTER TYPE

SIDE RETURN

BOTTOM

RETURN

17-1/2 (445)