Building a down draft table

[Jim Dunn]

Looking for wiring information on a furnace blower that has 3 speed capacity.

How to wire with the 3 speeds being available with the flipping of a switch. There in lies the question, what kind of switch do I need for this unit.

The motor runs off of 3 independent leads with 1 common wire. Depending which wire is wired to the 115v circuit it will run fast or faster or fastest. Just asking where to purchas this switch.

Grainger comes to mind as one place but need the nomenclature of the switch so as I know what to ask/look for.

[Dan Stuewe]

This may be of little help, but when I looked for a switch for the 3-speed blower I used for my air cleaner, I found a toggle switch at Home Depot (I'm sure less than $10) that could handle 2-speeds and just chose to use the two top speeds. I don't know what they are called, but wiring it was pretty easy with one wire in and two out. On my toggle switch middle is off, up is wired for the high speed and down is wired for the medium (slow) speed.

[Bruce Shiverdecker]

There is a Rotory 3 Speed available from an electrical distributor.

Bruce

[Jeff Sudmeier]

There is a way to do this using two three way switches... what you do is wire the hot wire coming in to the gold screw of the first switch. Then run the slowes speed hot wire from the fan to the top silver screw on the first switch. Run a jumper from the other silver screw to the other switch's gold screw and run the other two hot lines from the motor to the two silver screws on the second switch... I would run the middle speed to the top silver screw and the fastest to the lower silver screw.

Now first switch up equals the lowest speed. First switch down gets you to the other switch. So first switch down and second switch up equals the middle speed, first switch down, second switch down gets you the fastest speed.

Have fun and email me if you have any questions.

[Steve Nelson]

This may be of little help, but when I looked for a switch for the 3-speed blower I used for my air cleaner, I found a toggle switch at Home Depot (I'm sure less than $10) that could handle 2-speeds and just chose to use the two top speeds. I don't know what they are called, but wiring it was pretty easy with one wire in and two out. On my toggle switch middle is off, up is wired for the high speed and down is wired for the medium (slow) speed.
Its called a double pole double throw switch

[Jim Dunn]

Thanks all who replied

Jim