Automate Kitchen Exhaust Hood Fan using inline ECM fan - Turbocharge yer exhaust!

[Denwood]

Just posting this here for reference:

I ordered up a few of the Zooz Zen54 0-10V dimmers (which work in North America, yay) and tested them out. Good news is that they work great right out of the box. Essentially you can turn an EC fan on/off and select speeds from 0-100 on the dimmer via Hubitat (or likely any other smarthub) using a generic zwave dimmer driver. This unit sends a voltage signal between 0 and 10V to control the EC fan. It's wireless commuicating over standard zWave frequency here. (908.42 MHz).

Max current on this unit is 4 amps, which should be fine for most EC fans up to 12". AC Infinity's 12" EC fan draws 2.5 amps max at 1600 CFM.

@jtp10181 over at the Hubitat wrote a custom driver for the Zooz Zen54 0-10V dimmer which works great.

[DRIVER] Zooz ZEN54 10V Dimmer Advanced

Zooz Modules Advanced Drivers HPM Package also includes: [Zooz ZEN53 DC Motor Controller] [Zooz ZEN55 DC Signal Sensor] Zooz ZEN54 0-10V Dimmer driver with the goal of exposing all advanced features and settings. If you are using this driver PLEASE like ❤ this post 🤝 Support my work by...

community.hubitat.com

I tested out the Zen54 0-10V zWave dimmer on an AC Infinity 4" CloudLine EC fan and it works a treat. Here is how it is wired. The Zooz dimmer is small enough to fit into the Cloudline Fan housing if you remove a bit of the corner bracing plastic inside the housing.

If connecting a dumb switch to toggle the fan on/off you would connect the blue wire (SW) from the relay to one side of the switch (instead of directly to ground as I have it shown), and connect the other side of the switch back to the grey (ground) wire.





So now there are two solutions to automate EC fans in North America. The Leviton ZS057-D0Z is more expensive, but does have a manual switch and manual dimming controls integrated. The Zooz Zen54 would be a great choice if simple on/off (via a dumb switch) and remote dimming control works for you. It can be set to remember the last powered up setting. It is small enough to fit behind a dumb switch in a standard electrical box.

 

[Denwood]

I swapped in the Zooz Zen54 0-10V controller into my kitchen fan setup so that I can now dynamically change fan speeds, as well as control on/off via the induction cooktop power



I can confirm that the TerraBloom EC fans work very nicely with the Zooz Zen54 0-10V dimmer. The one in my kitchen is a 6" EC fan with metal case.

Connect the Zooz Zen 54 grey wire to Terrabloom black wire (using their DIY wiring plug)
Connect Zooz Zen54 violet wire to Terrabloom blue wire (using their DIY wiring plug)

Terrabloom red and yellow wires are not connected.



This is a bit of a mess as I connected up everything first to make sure it all worked. The Zooz Zen54 "switch" wiring (just dry contacts really) are connected to the exhaust hood's existing fan switch. The "load" wire goes up to power the Terrabloom fan on and off, as do the 0-10V wires to control it's speed. It all tucks up under the hood's metal connection shielding.

I've got some simple code in place right now that works like this:

If the induction cooktop is powered up, then the Hubitat hub turns on the EC exhaust fan to 100% for about 90 seconds (about 160 CFM measured at the hood). This extra pressure pops the flap on the exhaust hood outside if it's frozen in place. Full speed is not needed normally so I then ramp the fan down to about 50% (about 100 CFM) which is quiet, and does an excellent job of extraction. When the induction cooktop power use drops near zero, the fan stays on for 3 minutes, then turns off. The old switch on the exhaust hood can still be used for manual control, but the automation stuff ignores it's position.

I'm tuning it up a bit so that the power level on the cooktop will control the fan speed. Perhaps the ultimate smart kitchen fan?

The HRV is also now set up to provide make up air for the kitchen exhaust. The kitchen exhaust fan turning on triggers an asymetric profile (more air comes in the house than leaves) on the HRV system. The end result is pretty much zero cooking odour etc. , and it all runs by itself

I know folks here don't get too fired up over automation, but I can post up more details if requested.

Here is what I sorted to have the kitchen fan speed set according to power use on the induction cooktop, with 1:30 seconds of max speed to pop the exhaust hood flap:

1st I needed to figure out a relationship between induction power and dimmer settings. I did that here: https://www.calculator.net/slope-calculator.html?type=1&x11=250&y11=40&x12=4000&y12=99&x=14&y=18

I figured when the induction cooktop is at 250 watts, I want the fan at 40% and with power at 4000 watts, the fan should ramp to 99%. Plug those numbers into the graphing web site above and you get "Dimmer Setting" = 0.0157*(Induction Power in watts) + 36. The equation I'm using in the 3rd pic here is actually dimmer=.02*induction power + 34



Turns fan on with cook top use and sets it to full power for 1:30 seconds, then ramps it down to 50%. At this point, the speed will be set dynamically every time power use changes on the cooktop.



Modifies the kitchen fan speed every time power level on induction cooktop changes...but not until it runs at full power for 1:30 minutes. I set a variable, then do some math on it to arrive at the "correct" dimmer setting for the fan.

 

[dpalinsk]

Wow, your documenting this project has been very informative and helpful to decide whether or not I can dump the obnoxiously loud range fan for an inline fan installed in my attic! I appreciate you for putting in the time it must have taken you to document all it. As an old programmer, I really liked how you incorporated the home automation components.

I don’t think it will be too difficult to complete this project, but I’m wondering what your thought are on whether I need go with the Terrabloom 6” Silenced unit, install a Fantech silencer or just go with same unit you installed? The other question I have is if you think there would be any issues going from 7” duct into the 6” fan and back out to 7” duct. Thanks for your help!

David