humidistat+switch to run bathroomfan???
myhomereno
| Posted in Energy, Heating & Insulation on
I am in the final stages of my bathroom Reno but need so electrical advise:
Is it possible to run a remotely installed bathroom fan with a humidistat and a switch at the same time? I want the fan to turn on when a certain amount of humidity (during a shower) is in the bathroom. When the excess humidity is extracted the humidistat turns it off. But I also want to turn the fan on manually with a switch (timerswitch 5-30mins.) when somebody takes a poop.
Hope this makes sense and somebody can help me out.
Thanks Martin
Replies
Yes you can, you have to parallel the connections for the timer and humidistat.
One way to wire it would be to bring power to the fan, then a switch leg to the humidistat, with the white wire, remarked black as connnect to the black hot from the supply. And the humidstate connected from the white to the back and the back connected to the fan. Then from the humidstat continue the can switch leg to the timer switch.
And anothe way to wire it would be to bring power to the timer. The 3 conductor cable to the humidistate. Connect the timer from the hot (back) to red (switched hot). Then at the humidstat connect it the same way, between the black and the red. Then run a 2 conductor cable to the fan, with the black connected to the switched hot (red).
Just make a scketch of this and put a copy in the timer box so that the next person that runs across this will know what is going on.
My sometimes wonderful red-headed other half though the idea of the Nutone Bath Fan with the builtin humidistat was a wonderful idea. I was disappointed to find that it was not easy to add a timer in parallel.
You can get standalone humidstats to tie with any bath fan (and timer if you want).
If you buy the right fan, there is no reason not to have the thing running whenever there is someone in the bathroom. Thus, I would bypass the issue of a humidistat and timer and simply install an occupancy sensor.
I Installed a occupancy sensor in all my bathrooms which is made by Leviton. It is powered by a power-pack that can furnish 24VDC for up to three occupancy sensors. Whenever someone enters the bathroom, the fan comes on (the Leviton relays are rated for 120VAC use), and a manually-set timer in the occupancy sensor leaves the stuff running for 5 minutes after the activity in the bathroom has ceased.
KISS and I can't take any credit for it (that belongs to a helpful tech at Lifebreath). Instead of fans, I'm using the HRV system on high speed to exhaust the bathrooms, but it's the same idea.
Edited 7/31/2005 9:56 am ET by Constantin
I like the idea of an occupancy sensor for bathroom lighting but not for fan control. If the fan turns off 5 mins after you leave the bathroom there is not all the excess moisture removed from the bathroom. That's why I want to put in a humidistat.
That is a very good point. In an ideal world, you'd have a humidistat + an occupancy sensor so that that either event would trigger the HRV to kick into high-speed. I'm simply going to make do by taking a long, hot shower, kicking the HRV into high gear and observing how long it takes to reduce the humidity to normal levels. Then, set the timers in the respective occupancy sensors to ensure that they clear the air, so to speak (the Leviton occupancy sensor timer is adjustable).