Looking for way to control fan speed

mikepurt

New Member
I just ordered some whole house ventilation fans from Quiet Cool Whole House Fans.
I'm interested in having some automated control over the speed of the fans.

I'm assuming (right or wrong) that it's not a good idea to use a dimmer control on one of these.

Does anyone have suggestions for automated speed control of these fans? They're 120VAC, 150 watts.

I'd prefer something with a control input in the form of dimmed VAC ouptut from something like an Insteon dimmer, a DC control voltage (from Elk zone output), or RS485.

I have an Elk1M gold, some Elk temperature probes, an ethernet RS485 interface and custom software running on a PC that I'll use to tie it all together.

Thanks,
-- Mike
 
If these only produce 0.4 sones when running, why do you want to control the speed? A relay switch will control it for simple on/off, any of the automation methods you listed would handle 1.5 amps.
 
Bruce has a point. I think some have said they have used insteon dimmers with ceiling fans but it was suspected that it could reduce the life of the fan depending on how it was used.

I had a traditional whole house fan which I just took out (I put in central air). It worked great but it was very loud. I can imagine this approach is much better. Interesting product, good luck.
 
Yeah, you're probably right. I'll start out with some Insteon relays.

Although I think they'll be much quieter than a traditional whole house fan, I guess I'm a bit skeptical of them being as quiet as they claim and my mind is preparing for a solution that I may not need.

Thanks for the responses!
-- Mike
 
Out of curiosity, do you now have, or plan to have central air in the future? I was wondering if you saw this complementing (in which case the multiple vents might be annoying) or replacing a central air solution.
 
MikeP,

Just as a FYI...

I once had an Insteon dimmer controlling a cheap box fan. The fan worked well but the fan motor died after a week. At the time, one of the SH folks stated that the Insteon dimmers will and can control fan motors. I decided otherwise.

I, personally, would never connect a (expensive) fan motor to a Insteon dimmer.

My 2 cents.

Ken
 
No AC right now, but yes, we plan on getting it soon and the ventilation is intended to compliment the AC.

It's very unusual for us to not get down into the 60's or cooler at night. So the AC would only be used on the dozen or so days a year when we're home during the day and it gets uncomfortably warm. We don't get much for a breeze in the evening, so if the house heats up during the day it doesn't usually give the heat up very easily and this is what I'm targeting these fans for. Now, I just go around the house, open windows and put some fans in the upstairs windows to exhast the warm air and pull cool air in through the downstairs. That works fine, but I think automating it will do a better job of keeping the house near a certain temperature and it's a lot more fun to do the automation. :) With the new fans, I can just leave cracks in all the windows and let the Elk decide when any of the fans should kick on because it's cooler outside than it is near any of the fans. Another benifit that I'm looking to is in cooling down the attic as I think that keeps the house from cooling down faster than it otherwise would.

Fan speed control would enable more fine control. If it's 75 inside and 55 outside and I'm shooting for 72 inside, then I'd rather run the fans slowly so that there's not a chilling blast of air near the windows with cracks in them. One fan will be in its own "zone", but the other two will share a zone so I can just turn one of those on for this scenario.

-- Mike
 
KenM said:
MikeP,

Just as a FYI...

I once had an Insteon dimmer controlling a cheap box fan. The fan worked well but the fan motor died after a week. At the time, one of the SH folks stated that the Insteon dimmers will and can control fan motors. I decided otherwise.

I, personally, would never connect a (expensive) fan motor to a Insteon dimmer.

My 2 cents.

Ken
This explains why:
http://www.act-solutions.com/kingery02.htm

And this is a X-10 based no-hum fan controller. Should be able to use it with Insteon too:
http://www.edcheung.com/automa/nohum.htm

I have an old fan that came with a 5 speeds controller. It looks like a multi-tap tansformer. I should not be difficult to control the transformer from the M1G using relays. That's another option, but you must check that the motor would not overheat. As said before. it would be wise to ask the manufacturer.
 
Whole house fans really work. I live in North Central KS and it gets HOT here > 100 most days. At night usually gets down in the low 70s. Our AC died at the end of last summer and to replace it would be over 8K (old system, new ducts, etc). So this spring I put in a whole house fan, one of the big ones - yes it is very loud but it's at the opposite end of the house so it doesn't bother us when sleeping.

We run the fan all night and close up the house before we leave for work in the AM. When we get home at the night ground floor is tolerable and the basement is downright chilly.

Whole house fans are a good choice tradeoff between cost and comfort.
 
MikeP,

You stated that Smarthome "at the time" claimed fan speed control. Do you know if they rescinded that claim?

Just curious.

FYI I control a BROAN Bathroom fan with an Insteon Dimmer. No issues to date and its been in for a few months (although that dimmer was never linkable for some reason so its an expensive local fan control).
 
Digger,

You may have got my post mixed up with MikeP's. I did indeed hear that from SH several months ago. The latest I have heard (from the Smarthome forum) is that controlling at an extremely low speed is not advised as there is a possibility of motor damage. Other than that they believe the Insteon dimmers will control fan motors.

After reading the article linked in this thread, it appears that it is pretty much up to the fan motor as to how well this will work. I managed to kill an 'el cheapo' box fan with an Insteon dimmer and later killed a plug in Insteon relay module with the replacement fan by just doing normal on/off cycles. My fan control experiments are over. I bought a manual variac to tune the speed on my attic fan.

Ken
 
Back
Top