Internal, inline and external range hood blowers

There are three basic forms of range hoods blowers:

• Internal range hood blower - the range hood blower is located inside of the range hood canopy
• Inline to the duct run - the range hood blower is located somewhere along the range hood exhaust ducting
• External to the range hood - the range hood blower is located either on the roof or on an external wall

Internal range hood blower

External range hood blower

Inline range hood blower

If the cooking equipment - the stove or the range dicatate (based on the btu to cfm calculation that can be found on posts in this blog) that around 600cfm is required then there is not a great deal of benefit to be achieved by placing the range hood blower remote from the range hood canopy

Noise is one of the main reasons why remote blowers for range hoods are installed. If the range hood blower, whether inline or external is close to the range hood very little benefit in term so of noise reduction will be achieved.

An external blower mounted on the wall directly behind the range hood without any bends in the duct run will not help the noise a great deal.

For optimal noise reduction from an external blower there should be at least one 90 degree bend in the duct run.

For optinal noise reduction a duct silencer system can be placed in the duct run.

Duct silencers