low motor amperage

[icedr024]

On my main air handler, will the fan motor draw less amps if the return damper shuts. Or will the amperage go up due to the motor working harder trying to pull back air causing amps to go up.

[flange]

depends upon the fan type, but most likely it will go down from moving less air.

[icedr024]

depends upon the fan type, but most likely it will go down from moving less air.

Ya thats what im thinking thanks.

[GT Jets]

On my main air handler, will the fan motor draw less amps if the return damper shuts. Or will the amperage go up due to the motor working harder trying to pull back air causing amps to go up.

If this is a squirrel cage or backward incline, the amps will drop, but only because you are moving less air...

Think of what happens to a vacuum cleaner if you plug the suction hose with your hand....Does the motor speed up, or slow down? It speeds up because you have removed a major portion if the load from the impeller..

On a propeller fan, typically the fan will slow down, propeller fans are great for moving mass quantities of air, but can't build much static...

GT