[NA] - Whole House Fan - Programmable Timer Switch

G-Man

G-Man

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Non-aviation - need help, please. I have a whole house ventilation fan. It's either a Dayton 5NRT2 - 1/3 hp, 120 volt, 5.8 amps on high and 2.8 on low. Or it's a Dayton 5NRT1 - 1/3 hp, 6.2 amps on high and 3.9 amps low.

It came with a high-low switch and a mechanical timer - rotate knob and it runs for X hours.

I want a programmable timer switch, to be able to program the fan to turn on at a certain time and off a specific time. Bonus if it lets me program multiple days. And a master on-off.

I've been unable to find such a switch. I'm ignorant about thi - apparently there are issues turning on electric motors versus other stuff.

Anybody have switch suggestions? Much appreciated!
 
at it's simplest you could use the existing switch in series with a simple timer like you'd use for lights when you're away on vacation
 
You could put a plug on the fan and install an outlet then by a plug in timer. They have some nice plug in timers. There are some with 7 day programming. I was just looking because I need on for the frost heater on my car. I just bought the cheap one because that was all I needed.
 
I was told there are special issues since the switch will control a 'big motor.' That it needed to be able to deal with 'the start-up inductive load' or similar?

Any thoughts on this?
Or could any 10amp-capable timer switch handle it?
Thanks...
 
I took mine out and installed an on/off switch. Thank you......I'll be in control of my fan.
 
G-Man said:
I was told there are special issues since the switch will control a 'big motor.' That it needed to be able to deal with 'the start-up inductive load' or similar?

Any thoughts on this?
Or could any 10amp-capable timer switch handle it?
Thanks...
Click to expand...

6 amps or so is NOT a big motor....:no::no::no:..

Any timer will work...
 
I have long considered installing a whole house fan and instead on putting it on a switch or timer, putting it on an automatic temperature differential whereby it would turn on and off based on exceeding some set temp difference.
 
G-Man said:
I was told there are special issues since the switch will control a 'big motor.' That it needed to be able to deal with 'the start-up inductive load' or similar?

Any thoughts on this?
Or could any 10amp-capable timer switch handle it?
Thanks...
Click to expand...
look at what size CB the fan is on and get a timer to match
 
FORANE said:
I have long considered installing a whole house fan and instead on putting it on a switch or timer, putting it on an automatic temperature differential whereby it would turn on and off based on exceeding some set temp difference.
Click to expand...

This is what I want to do as well. But it needs to recognize the humidity as well, not just temp. Sucking in air that's a few degrees cooler, but 90% is not good. Cooler and dryer is what I want it to do.
 
The timers I looked at had ratings for size of motor and current draws. Just look for what you need.
 
Pedals2Paddles said:
This is what I want to do as well. But it needs to recognize the humidity as well, not just temp. Sucking in air that's a few degrees cooler, but 90% is not good. Cooler and dryer is what I want it to do.
Click to expand...


Piece of cake......

http://www.grainger.com/product/DAYTON-Line-VControl-1UHG9?s_pp=false&picUrl=//static.grainger.com/rp/s/is/image/Grainger/1UHG9_AS01?$smthumb$
 
That doesn't monitor OUTDOOR temperature and humidity. Only indoor.
 
I use these on my outdoor lights house lights. You can program them on/off relative to sunrise/sunset, or just set a schedule for each week day. A bit expensive but is worth it.

Search on Amazon:
Honeywell Econoswitch RPLS740B 7-Day Solar Time Table Programmable Switch for Lights and Motors
 
Such problems that I didn't have when I installed a whole house fan in our house in the Denver area... Of course, that was over 30 years ago and the high/low/off switch was the option. BTW, that fan, coupled with a well insulated house, eliminated any thoughts of adding air conditioning. Worked like gangbusters.
 
G-Man said:
I was told there are special issues since the switch will control a 'big motor.' That it needed to be able to deal with 'the start-up inductive load' or similar?[snip]
Click to expand...

The issue is that motors pull their highest current load at startup. On a motor with a full data plate that will be listed as LRA or Lock Rotor Amps, meaning the current drawn if the rotor is stopped. That's the load that the switch contacts have to handle as they close. This is much higher than the equivalent load for a lighting circuit or a heating (resistance) load. Motor rated switches have much thicker silver on the contacts so that they don't burn out and oxidize from the arcing.

That said, I've seen stuff in this thread that will work in terms of the load. Timers, etc. that are rated for lights and motors should be fine.

If you use a lighting only switch it will work. For a short time. Then it will start arcing internally all the time it's on and get very hot (think melting and fire hot).

On thing you could do is get an external controlled motor contactor and get whatever type or thermostatic/humidity/timed control to control the contactor.

John
 
Just want to say "Thank you" to everyone who contributed to this thread. Lots of good stuff here, and I appreciate the info.
 
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