Nortek B5BM, Installation Instructions Manual

5

handler must be cleaned and/or repaired if found to 
be dirty, damaged, or malfunctioning in any way by 
a qualified HVAC technician. The air handler shall be 
inspected and approved by applicable local authority 
even if this requires redundant inspections.

•  The  serial  number  for  the  air  handler  used  during 

construction must be submitted in writing (fax and 
email also acceptable). This information will be used to 
track the long-term affects of air handler usage during 
construction. Proof of this submittal shall be available for 
the final inspection of the air handler prior to occupancy.

Installation in a Garage

 WARNING:

Do not place combustible materials on or against 
the cabinet. Do not place flammable materials, 
(gasoline, paint thinners, etc.) or any other 
flammable vapors and liquids, in the vicinity 
of the air handler.

The B5 Series air handler may be installed in a residential 
garage with the provision that the unit must be located or 
protected to prevent physical damage by vehicles.

as the opening provided on the blower coil unit. The 
ducts should be appropriately sized to the capacity of 
the air handler to ensure its proper airflow rating.

•  Use  transition  fittings  if  the  supply  and/or  return  air 

openings of the unit do not match the duct openings. 
These transitions should be dimensioned in accordance 
with standard practice as specified in the ASHRAE 
recommendations for duct transitions.

•  Flexible connectors should be used between the unit 

and the ductwork to prevent transmission of vibration 
from the unit to the structure. If electric heater kits are 
installed, heat resistant material must be used for the 
flexible connector at the supply air end of the unit.

•  Seal  all  connections  and  joints  with  industrial  grade 

sealing tape or liquid sealant. Requirements for sealing 
ducts vary from region to region. Consult with local 
codes for requirements specific to your area.

Unconditioned Spaces
All duct work passing through unconditioned space must 
be properly insulated to minimize duct losses and prevent 
condensation. Use insulation with an outer vapor barrier. 
Refer to local codes for insulation material requirements.

Air Filters
B5 Series Air Handlers are not supplied with an air filter 
when shipped from the factory. The installer must provide 
a high velocity filter that is appropriately sized to the return 
air duct opening or filter rack located in the bottom of the 
unit. Accessing the filter does not require tools and can 
be removed from the front of the unit by removing the filter 
door. See Unit Maintenance (page 14) for filter sizes and 
other important information.

 WARNING:

Never operate the air handler without a filter 
or with doors removed. Dust and lint can build 
up on internal components, resulting in loss of 
efficiency, equipment damage, and possible fire.

Acoustical Duct Work

• 

Certain installations may require the use of acoustical 
lining inside the supply duct work. Acoustical insulation 
must be in accordance with the current revision of the 
Sheet Metal and Air Conditioning Contractors National 
Association (SMACNA) application standard for duct 
liners. Duct lining must be UL classified batts or blankets 
with a fire hazard classification of FHC-25/50 or less.

•  Fiber duct work may be used in place of internal duct 

liners if the fiber duct work is in accordance with the 
current revision of the SMACNA construction standard 
on fibrous glass ducts. Fibrous duct work and internal 
acoustical lining must be NFPA Class 1 air ducts when 
tested per UL Standard 181 for Class 1 ducts.

• 

Damping ducts, flexible vibration isolators, or pleated 
media-style filters on the return air inlet of the air 
handler may be used to reduce the transmission of 

Plenums & Air Ducts

• 

Plenums and air ducts should be installed in 
accordance with the standards of the National Fire 
Protection Association Standard for Installation of 
Air Conditioning Systems (NFPA 90A), Standard for 
Installation of Residence Type Warm Air Heating 
and Air Conditioning Systems (NFPA 90B), and all 
applicable local codes. NFPA publications are available 
by writing to: National Fire Protection Association, 
Batterymarch Park, Quincy, ME 02269 or visit 

www.NFPA.org online.

 WARNING:

All return ducts must be secured to the air 
handler using appropriate methods. All return 
ducts must be adequately sealed. When return 
air is provided through the bottom of the unit, 
the joint between the air handler and the return 
air plenum must be air tight.

Return air and circulating air ducts must not be 
connected to any other heat producing device 
such as a fireplace insert, stove, etc. This may 
result in fire, explosion, carbon monoxide 
poisoning, personal injury, or property damage.

•  Design the duct work according to methods described 

by the Air Conditioning Contractors of America (ACCA).

• 

This unit is designed only for use with a return and supply 
duct. The return air duct must have the same free area