Comparing Motors

Comparing Motors

motor-numbersMotor Anatomy

This section provides a more detailed analysis of the anatomy of a central vacuum motor. It will help you become familiarized with terms you may encounter when comparing central vacuum systems.

The illustration on the left shows a Thru-Flow motor while the one on the right is a Tangential Bypass motor.

Note: Only the Tangential Bypass has a Motor Cooling Fan (1).

Both motors have the following elements in common:
(2) Motor Carbon Brushes
(3) Field laminations and Armature
(4) Fans. The number of fans stacked equals Stages. A two-stage motor has two fans while a three stage has three fans.


The Peripheral-Bypass Motor

In addition to the Thru-Flow and Tangential Bypass motors, there’s actually a third motor type we really haven’t addressed since it is not commonly used. This is called a Peripheral Bypass motor.

Peripheral Bypass motors share the same benefits as Tangential Bypass motors. They both have dedicated cooling separate from vacuumed air which means both should have a longer life expectancy.

The difference between the two is how they exhaust vacuumed air. The Tangential Bypass has a horn that attaches to PVC plumbing and a muffler to vent away from the motor. The Peripheral Bypass motor vents exhaust air around the motor.

At Cana-Vac, a Tangential Bypass motor is the preferred and most popular choice because heated exhaust air is removed from the motor chamber and vents contaminated exhaust air away from your living environment.

Motor Manufacturers

Ametek/Lamb is generally regarded to be best choice for central vacuum motors. Much like a Briggs and Stratton lawnmower engine, this brand instills confidence. In other words, you know you’re getting quality.


Ametek/Lamb is the only motor manufacturer with an 8.4 inch diameter motor with Infinity™ brush technology that extends motor carbon brush life. They have a diverse assortment of quality motors and are also the only motor manufacturer with a 6.6 inch diameter motor.

While there are other motor manufacturers available such as Domel (another popular choice), Cana-Vac only uses genuine Ametek/Lamb motors.