Status for Attic Roof exhaust fan needed

I have an attic exhaust fan that recently failed. That isn’t the problem as it has a lifetime warranty. The replacement is installed and I need to know status if ON or OFF. I had a SmartThings multisensor on it prior and it failed to last very long, as the battery was dead in a short time. I tried soldering on a USB power supply and it worked but the sensor itself failed. Is there any other solution that has a real long battery life, and is more robust?

What are you trying to detect from it?

Using a multi sensor are you using the vibration? Or the Contact Sensor somehow?

I would use a Smart Plug that has energy monitoring (Iris Smart Plug) and plug the Attic Fan into it.

Typically there’s a switch that the fan gets it power from. Install an outlet off the load (think lamp that gets turned on by a switch), then install a cord onto the fan.

Created Virtual Switch

Use webCoRE to say:

If power rises above xxx Watts
Then using switch
Turn On
Else
Turn Off

Not 100% sure I’m following you. So, the fan gets turned on by a switch…why not change that switch into a smart switch. Bing, bang, boom…you’re done.

Of does the switch control the fan power on but then a thermostat or humidity sensor actually turns the fan on to exhaust?

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are you talking about a whole house fan or an attic soffit fan?

I might have a solution…

This an automatic attic exhaust. Goes on by heat or humidity. The switch is always on. That is why I used the multisensor that has a vibration sensor.

If you have a spare smart relay laying around you could do this… connect an air reed switch to the fan, run wires down to air conditioned parts of the house, connect the smart relay. When the fan turns on it will close the air reed switch. That closes the circuit and triggers the smart relay, thus telling ST that the fan is on.

I would use an energy monitoring device. Like this:


You would wire the actual fan power into this first. This has energy monitoring in ST.

Ryan, I am using two now for my washer and dryer. But being an electrician I have to follow local electrical codes. Using an Attic exhaust fan via a plug isn’t allowed. Yes I could remove the plugs on the end and put it into the electrical box, but that wouldn’t allow the signal to pass. And having it outside the box violates the code. Also, plastic boxes in attics is also a violation. If, it was an independent circuit not feeding anything else I could place that below the ceiling in a plastic box. But it is and re-routing would be very hard. My attic space at the peak where the cable is accessible is twenty feet high. I gave up climbing many years ago. That is also why I stopped using the sensors on the fan as it is way too high a climb. I just thought about something, isn’t there a switch that reads power? I thought I read it somewhere.

Enerwave ZW15SM-PLUS Z-Wave Plus Wireless Switch with Smart Meter Energy Monitor.
I have not used this but it appears to be what you asked about.

Where are you located? I just added a box in my attic and did a LOT of research before I did and never saw that mentioned anywhere.

Every state, every county, every city… they all have something different in the code. Why do you think it takes so long to build something… 2 days for a team to build a 2 story house, 2 days to wire it, 2 days to plumb it, a day to dry wall, and another 2 days to finish everything else… but it takes 6 months because you’re always fixing code violations which change with the inspector’s mood…

oh sorry… I got distracted… I have plastic boxes in my attic too.

I’ve used a current sensing relay along with ST_anything (although you could use a EcoLink contact sensor too) to do this with my non-smart garage heater. Wrap the fans hot lead around the current sensor. Used the same on my furnace fan to know when it was running before I got my EcoBee also.

They are relatively cheap and reliable sensors if all you need is on/off.

Yes there is National Electrical code and that is the foundation, then city codes and state codes come on top of those. So many times the local code is more stringent than the National code. Many local codes are suited to conditions in that area either environmental, or just for safety reasons. I gave up when I worked in NYC as there are codes up the kazoo. There is NYC code, then Port Authority Code then Amtrak code. So some jobs are codes on top of codes. The Port Authority even had their own color code for wires.

I am a little confused! I won’t be using ST anything too involved. So what device works and how?

Okay…but you didn’t answer my question and you don’t have to but I couldn’t find anything in the NEC about plastic boxes in an attic. Do you have a link or something to where you found that regulation? There’s been a lot of talk about code but no one’s shown me one that says that yet. Thanks.

My house. My code… lol

See, when you say “violation” that implies something stronger than your personal preference. Thanks for clarifying that you were completely pulling that out of thin air.

Since my home is BX NOT Romex you must use metal boxes. That is in the National Electrical Code, look it up.

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A current sensing relay just clicks on and off when it detects some amount of current. Need to find out how much current your fan draws and then make sure you get a current sensing relay that can detect that level or lower. And all it will do is open and close a relay which you could then use the output of on a cheap ecolink contact sensor since they have external input terminals on them. I can’t imagine a small current sensor relay being more than $20 and I’m pretty sure that you get the EcoLinks around that too.

OK I get your idea. Now to get up to the unit to see the draw as the cable isn’t down low and accessible. I wonder if there is an adjustable current sensing relay.