Inline and Multiport Fans

Detail ID
6.0201.3
Topic
Local Ventilation
SubTopic
Exhaust Systems
Desired Outcome

Efficient, safe, durable, and airtight fan installation that maximizes air flow

SF Single Family Site-Built Housing
MH Manufactured Housing
MF Multifamily Housing

Specifications

  • SF
  • MH
  • MF
Specification Objective

Select a fan that:

has an electrically commutated motor (ECM)

has an efficacy of 3.8 cfm/watt or more

Efficient fan selection

  • SF
  • MH
  • MF
Specification Objective

Select sealants that:

are compatible with their intended surfaces,

allow for differential expansion and contraction between dissimilar materials,

meet the requirements of the applicable fire safety code (e.g., thermal or ignition barriers), and

for use inside the pressure boundary select low volatile organic compound (VOC) sealants that meet independent testing and verification protocols

Select safe and effective sealant

  • SF
  • MH
  • MF
Specification Objective

Install all electrical wiring according to manufacturer specifications and applicable code

Prevent an electrical hazard

  • SF
  • MH
  • MF
Specification Objective

Orient the fan outlet toward the final termination location and so the equivalent length of the duct run is as short as possible

Short, effective fan venting

  • SF
  • MH
  • MF
Specification Objective

Mount fan using mechanical fasteners and per manufacturer's specifications so that fan housing does not shake, rattle, or vibrate when operating

Securely mounted fan

  • SF
  • MH
  • MF
Specification Objective

If the fan does not contain an integrated damper, install a damper that:

opens in the direction of the desired flow

closes when the system is off

Prevent unwanted air movement while not restricting desired air flow

  • SF
  • MH
  • MF
Specification Objective

Cut hole for intakes leaving no more than a 1/8" gap on each side

Install register boots using mechanical fasteners sufficient to prevent movement

Durable intake boots with properly sized opening

  • SF
  • MH
  • MF
Specification Objective

Seal gaps around intake register boots with compatible sealant

Airtight fan installation

  • SF
  • MH
  • MF
Specification Objective

Ensure fan and service disconnect switch are accessible for maintenance according to NEC, or applicable building code

Accessible for service

  • SF
  • MH
  • MF
Specification Objective

Duct and terminate fan to the outdoors, which does not include unconditioned spaces such as attics and crawl spaces that are ventilated with the outdoors, in accordance with SWS detail for "Ventilation Ducts"

Exhausted to outdoors

View Sub-Topic:
Exhaust Systems