dimming fans??

[crazylegs]

I know i have read its a very bad idea to use a light dimmer switch to slow down a fan but what can you use then? I have a decent size squirrle cage fan, it is pushing a ton of air but its just to much. it is very loud and i think if i could just slow it down a bit it would be perfect. thanks for any help!!:rastasmoke:

[MVP]

Huh? I run my Vortex inline and smaller muffin (box or PC) fans on a dimmer rheostat without problems. Where did you read that?

[attachment=o173004]

[Atkeni]

Your fine to undervolt most fans, with most fans a 10% drop in speed can halve the noise.

[crazylegs]

i will find the links later to show what i meant about it not being a good idea.
But really as long as other people are using them then im not going to worry to much about it.
ATKENI- it seems that would be true. just anything but full blast on this one would be a ton better. my closet is only like
3x2 and its got this heavy duty cage fan on it. a little OD:stoned:

[okwtfo]

I think that it DOES put stresses on the motor to slow the fan down with a rheostat. I have heard that myself and the sound that my motor gave off, when I did it, sounded bad. Probably would just shorten the lifespan of the motor. But those motors last quite a while. Why not just attach your fan to a piggyback thermostat? It will turn itself on/off as needed. I guess this will not take care of the volume when it is on though, huh?

[PharmaCan]

I know i have read its a very bad idea to use a light dimmer switch to slow down a fan but what can you use then? I have a decent size squirrle cage fan, it is pushing a ton of air but its just to much. it is very loud and i think if i could just slow it down a bit it would be perfect. thanks for any help!!:rastasmoke:

Light dimmers aren't designed for much of a load and most of them start (turn on) on the low side and progress to high. A fan dimmer, on the other hand, is designed for a heavier load and it starts on the high side, which is better for the motor. Taking these factors into consideration, you DON'T want to use a light dimmer on a fan.

However, since you will most likely just set the rheostat (dimmer) and turn the fan on and off with your timer, where/how the dimmer turns on is not a consideration and your concern should be to get a dimmer that is designed to handle the load from your fan. If going to Lowe's or Home dePot, unless you have a really big fan, just get the mid-priced dimmer with the slide bar not the knob; around $10 if I recall. Using a rheostat on your fan won't hurt the motor. It could theoretically shorten the useful life of the motor by a small percentage, but so what? The bearings in your fan will wear out long before the motor ever does.

PC :smokin:

[Atkeni]

Light dimmers aren't designed for much of a load and most of them start (turn on) on the low side and progress to high. A fan dimmer, on the other hand, is designed for a heavier load and it starts on the high side, which is better for the motor. Taking these factors into consideration, you DON'T want to use a light dimmer on a fan.

However, since you will most likely just set the rheostat (dimmer) and turn the fan on and off with your timer, where/how the dimmer turns on is not a consideration and your concern should be to get a dimmer that is designed to handle the load from your fan. If going to Lowe's or Home dePot, unless you have a really big fan, just get the mid-priced dimmer with the slide bar not the knob; around $10 if I recall. Using a rheostat on your fan won't hurt the motor. It could theoretically shorten the useful life of the motor by a small percentage, but so what? The bearings in your fan will wear out long before the motor ever does.

PC :smokin:

I dont mean to be a pain, but all the dimmers in my house Start on high, and go to low, and all of them can also be pressed to start the light (at whatever speed you want). Dimmers come in all shapes and sizes- not to mention you only set the dimmer once if its on your timer circuit, so at most this would benifit once

also, i would assume a light dimmer is rated for more than a fan dimmer, a PC fan consumes 1-2w tops, most heavy duty fans max out at not much higher. where a light is an easy 60-120w (old style)

I could be mistaken, but it doesnt seem right to me.

[MVP]

Light dimmers aren't designed for much of a load and most of them start (turn on) on the low side and progress to high. A fan dimmer, on the other hand, is designed for a heavier load and it starts on the high side, which is better for the motor. Taking these factors into consideration, you DON'T want to use a light dimmer on a fan.

However, since you will most likely just set the rheostat (dimmer) and turn the fan on and off with your timer, where/how the dimmer turns on is not a consideration and your concern should be to get a dimmer that is designed to handle the load from your fan. If going to Lowe's or Home dePot, unless you have a really big fan, just get the mid-priced dimmer with the slide bar not the knob; around $10 if I recall. Using a rheostat on your fan won't hurt the motor. It could theoretically shorten the useful life of the motor by a small percentage, but so what? The bearings in your fan will wear out long before the motor ever does.

PC :smokin:

Agree with everything said except the 'slider not the knob' comment. If you choose the right one you will be fine. You can get this dimmer: Rotary 600W Dual Knob (http://www.lowes.com/lowes/lkn?action=productDetail&productId=211632-539-D-600PH-DK&lpage=none) that turns on with a push-in action and powers the fan up at the setting on the rheostat that you choose. In other words it doesn't require you to start at low power and dial it up. It is rated for 600W and costs less than 5 bucks.

MVP :jointsmile:

[jmello]

itll be fine i read that too a couple days ago you shouldnt use a LIGHT dimmer cuz theyre a little different...fans can create small amount of electrical currents when turned off and they somehow spin in the opposite direction (air current or wind) cuz theyre like little generators (at least the same idea with the coils and magnets and what not)

[trynagethigh]

also might i add to check the amperage that the rheostat will manage. its not the volts that will cook either its the amperage that will. the motor should have its amps draw listed on a sticker somewhere on it, just get the fan rheostat that will fit the amperage and you should be fine. and if you dont know what your doing messing with electricity, let someone who does hook it up for you, some things arent worth the risk.:thumbsup:

[Pepper]

This is not complicated. Just buy a ceiling fan control. They cost sightly more because it's not the same as a dimmer.

1.5 Amp White Slide-To-Off Quiet Fan Speed Control (http://www.lowes.com/lowes/lkn?action=productDetail&productId=70802-000000539-SFSQ-FH-WH&lpage=none)

Pick a fan controller with a higher rating if yours needs more than 1.5 amps.

[gainesvillegreen]

This is not complicated. Just buy a ceiling fan control. They cost sightly more because it's not the same as a dimmer.

1.5 Amp White Slide-To-Off Quiet Fan Speed Control (http://www.lowes.com/lowes/lkn?action=productDetail&productId=70802-000000539-SFSQ-FH-WH&lpage=none)

Pick a fan controller with a higher rating if yours needs more than 1.5 amps.

Listen to Pepper here. A/C motors, unless they come with variable speed build in, are not designed to run at varied speeds. A rheostat will increase resistance in the circuit which allows less power for the fan, causing the fan to spin slower than it should. This works for D/C circuits, but A/C is frequency modulated, not voltage. This can cause a lot of stress to the fan and can cause the motor to stall and overheat, with the possibility of catching fire.

Another difference between a rheostat and a fan speed controller is that a rheostat will operate from 0-100% whereas the fan controller will run something like 40-100%, which keeps the fan from stalling and becoming a hazard.

Fork out the extra $10 for all the good a real fan controller will do, it's worth it :D

[BobBong]

I've been running an 8" Elicent fan on a ceiling fan control dimmer without any problems.. I never run the fan less than 50% Power though as doing so reduces the quality of airflow greatly.

Dunno about fires though..

[norkali]

This thread is a perfect example of why growers should either take a class on basic electrical beforehand, or just hire a certified electrition for their grow rooms.

Why take that chance? Electricity does not mess around.

Neither does fire.

[gainesvillegreen]

I've been running an 8" Elicent fan on a ceiling fan control dimmer without any problems.. I never run the fan less than 50% Power though as doing so reduces the quality of airflow greatly.

Dunno about fires though..

If you are using an actual ceiling fan dimmer, then you are good. They are designed specifically for the purpose you are putting them to (except for the ceiling part :D)

There's actually a whole article about it on the main cannabis.com website. Cannabis.com dimmer for fan (http://cannabis.com/growing/electric-Can_I_use_a_dimmer_switch_to_control_the_speed_of_ my_fan.html)

[xcrispi]

I did a bit of reading before buying my blowers.

Dayton squirell cage fans are to be run at 100% only . No use of any solid state controllers / speed controllers . Says so right in the directions in about 4 dif languages .

Hurricane , Vortex , Can , Ecotek / centrifugal blowers can be used w/ fan controllers .
Peace
Crispi :jointsmile: