GE/Jasco Fan Controller: All speeds are 100%?

Are ceiling fans different than other 120V fans?

  • I just installed a 14287 in place of an existing manual solid-state “rheostat” that included an off position.
  • Install went great; recognized/connected to Samsung Hub on first attempt and I can turn the fan on/off via either physical switch or Samsung app.
  • Problem is that the fan runs full speed all the time regardless of physical or app setting. I might be able to detect a slight difference between 1% and 100% but, if I can, the 1% might actually be faster…
  • I’m hoping one of you smart guys know if it is because:
    a) it is not controlling a ceiling fan, but a small 120V squirrel-cage fan used for ducting heat away from the wood stove to another room?
    b) I wired something wrong?
    c) The new Jasco unit is malfunctioning?
    d) Something else?

Thanks in advance!

Short answer: if the fan motor itself doesn’t offer variable speed, there’s nothing the fan switch can do. Many exhaust fans are just on/off.

What’s the brand and model of the fan? And what kind of switch was it on before?

JDR: Your contributions to this forum are just amazing. Thank you.

The fan was previously controlled by an KBMS-13BV rotary knob with integral ‘off’ position.
Here’s a link to its datasheet:

I can’t access the fan now. (For reasons too gruesome to explain, it was mounted to the inside – not the outside – of a wall.) But in appearance it is very similar to

I’d be grateful for any insights you might have.

What DTH are you using? Did you go in and set your Low, Med, and High Thresholds?

Yes this, I had to go into the setting once before. For some odd reason it didn’t get set.

The links you posted for the similar fans are one speed fans. Unless the one you have is something else. Were you able to control the speed with the old manual rheostat?

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A rheostat would control the speed by varying the current supplied to the fan. Less current, less speed. There’s no way that the fan was not varied by speed with a rheostat connected.

Not trying to argue but a dimmer will dim a non dimeable LED bulb to a point as well. We do have capacitance speed fan out there so varying voltage/current will have similar effect as non dimeable LED bulb.

I hate to point out the obvious but a fan motor is not a bulb. I’ve never seen a fan with only one speed setting.

OK :slight_smile:

They are common for bath or kitchen exhaust fans.

They are also used for sheds and outbuildings.

In both cases these are typically used to remove moisture/steam from an area.

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Just because they only have a single speed doesn’t mean that they can’t be “slowed” with the proper rheostat. I would need to research the specs on each one which I’m obviously not going to do.

My point, the fan has a rheostat on it, that controls the fan speed. And since it has a rheostat on it, we can assume that it is working. Why assume the switch can’t control the fan. The OP already posted that this is solved because the settings were wrong in the devices properties. I don’t know why you’re belaboring the point.
Both of you need to set down the stick and step away from the dead horse.

See the following:

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I didn’t say a dimmer…i said a rheostat. If you’re going to be so strict with people then you have to impose the same requirements on yourself JD.

OK :slight_smile:

Covered in the same article at that link.

  1. I have heard of rheostat’s being used to adjust the speed of a fan, why wont this work?
    Rheostats, like potentiometers are glorified variable resistors. While they can be used to adjust the speed of a DC motor, its a big no-no on AC motors. AC motors need to run at preset voltage, motor speed, and current draw. It is a balanced system.

The point is that we still don’t know the brand/model of the OP’s fan, so we don’t know if it’s multi speed or single speed.

You asked if single speed fans exist. They do. They are a different design than a multi speed fan. The article I linked to goes into those design details.

A single speed fan has a single winding. Altering the current, such as with a rheostat, will cause the fan operation to be off frequency.

A multi speed fan has multiple windings, and the control will switch between those.

I know the OP’s fan was apparently controlled by a rheostat, but that doesn’t mean it was a good idea or that that mechanism should be replaced with a similar mechanism.

So I’m just trying to address the original question of why that particular fan is not offering variable speed. The smart device that the original switch was replaced with doesn’t work the way a rheostat does, because that’s not the way fan motor controls are designed to work.

Submitted with respect.


I maintain, put down the stick man. The horse is dead.

What was wrong with the settings? Just curious.

There are 3 settings in the device. They are the threshold for the settings of High, Medium and Low. The control simulates a dimmer, so you can set it anywhere from 0-99 but there are only 3 speeds. It hits those speeds at a set threshold that has to be set in the device.