Ultimate Climate Control

One of the main reasons I wanted home automation, was to increase the comfort level in my home. Sure, not flipping light switches has its own convenience, but achieving the ultimate comfort lies elsewhere; precisely, in automatic climate control.

With five people living under the same roof, ever since we built our house six years ago, none of us have been happy with the temperature throughout our home. Hot spots, cold spots and the never ending “tug of war” game of who gets first to change the thermostat’s settings had become increasingly irritating.

My wife likes it cooler, especially at night because we sleep with blankets, but our master bedroom usually runs up to 5 degrees warmer than the temperature set by the upstairs thermostat, so she often turns down the heat. My teenager, on the other hand, whose room is above the garage and runs up to 5 degrees cooler, oftentimes cranks up the heat. My two babies are just…well “collateral damage” in this game. Their bedrooms are more balanced but because they don’t sleep with blankets, 68 degrees is too cold and 80 degrees is way too hot.

This is how the overnight temperatures looked like before I began exploring ways to normalize the room temperatures*.

<img src="//discourse-cloud-file-uploads.s3.dualstack.us-west-2.amazonaws.com/smartthings/original/3X/e/e/ee908dcb2b09639136f13d2f3c269ecead372b06.jpg" width=“216” height=“400”

So clearly, we’ve had a severe climate control problem. My first thought was to add two new zones to our existing zoning panel. The price estimated for that project came up to roughly $3,000. Doable but I still needed to feed five people and my HA addiction :wink: So for obvious reasons, that didn’t work for me.

Then I read about “Smart Vents”. They seemed like a great idea to me, but far too many people argue that is actually a terrible idea for the HVAC system:


It’s a really bad idea to close off vents to a room. As energy expert Allison Bailes III notes on his website, most home heating systems are not designed for this. "… the system is designed for the blower to push against some maximum pressure difference. … If the filter gets too dirty or the supply ducts are too restrictive, the blower pushes against a higher pressure.” So when you close vents in rooms you’re not using, the blower will just push harder. Since the air pressure is higher, the leakage is greater. Depending on what kind of fan you have, different things happen, both of them bad. (Source: Are smart vents safe?)


Despite the bad reputation, I started playing with my “dumb vents” to see if they actually can improve my situation. Sure enough, closing vents in Master Bedroom lowered the temperature in our bedroom while increasing my son’s bedroom’s temperature. But doing so just turned my son’s room into an oven and our bedroom into a freezer.

Being able to shift the temperatures by closing the vents was enough to convince me to replace the “dumb vents” with motorized Keen Vents.

Two weeks later, the temperatures in our bedrooms looked like this:

Using vents cost me less than a 1/3 of what I would have paid to add new zones. I used 10 vents and four SmartSense Motion sensors.

Buying and connecting the vents to the ST hub didn’t give me the control I needed to normalize the temperatures. Luckily, @mike_maxwell was in the process of developing a smart app to control his Keen Vents, so I used his soon to be released Keenect Smart App, which really enabled me to control the vents

Thanks to SmartThings’ flexible platform, the Keenect App coupled with @bravenel ’s Rule Machine and combined with a mod version of @slagle’s Thermostat Mode Director I was able to solve a six year old problem at a fraction of the cost!

As for damaging my HVAC system, during my yearly HVAC check-up, the technicians confirmed that my “climate control system” has no effect on my heat pump. In fact, both technicians said that will stop by Lowe’s to grab a few vents for their homes.

* data courtesy of @mike_maxwell 's in-app report in upcoming Keenect Smart App


Project Timeline


Day 1 - 3

  • Replaced all of the vents in the bedrooms

  • Connected vents and sensors to ST and installed smart app

  • Temperature Sensor Calibration - set four SmartSense Motion Sensor on my desk and compared their temperature readings against an AccuRite sensor over a 2 days period. I thought for sure the results will be all over the place, but to my surprise, the ST sensors were within 1-2 degrees off compared to the AccuRite and even more surprising, they were constant among each other. So I was pretty happy.

I installed them in places away from the vents at similar heights. I also, went back into the old ST mobile app, which I had on my tablet and changed the settings of the sensors to show temperatures instead of motion. I created a room called “Climate control” and that’s my “monitoring dashboard”

Day 3 - 10

  • Modified device handler for the SmartSense Motion sensors to report on 0.1 temperature changes

  • Fiddling with vent opening. The smart vents allow you to set the opening of your vents from 1 to 100. At first, I thought that open/close it would be sufficient to balance the temperatures. But as the days went by, I learned that the level of opening is very important.

There are many variables to take in consideration when attempting to shift hot air from one room to another. Here are some of the things I had to deal with:

  • temperature on first floor influences the second floor’s temperature.
  • temperature raises when room is occupied (varies based on room size)
  • vent opening in one room is dependent on the vent opening in another room - I noticed that I cannot adjust one room without changing settings (up/down) in other rooms - this one was the hardest because it depends on which room is first/last on the main duct.
  • one open/closed door changes temp in other rooms
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I did an addition on my house, my existing structure overheats and the new section is a bit under. It’d be great to shut off unused rooms and open them when they’re in use to maaaaybe get some flow downstream to the new addition.

I will attest @mike_maxwell has been working hard and doing a great job of getting us a stable, functional, reliable control app for our keen vents. My room were not as bad as Bobbys but were always several degrees different, especially at night with our doors closed. Now they stay within a degree of the set point I set for each “Zone” using keen vents and a temp sensor in each room.

@mike_maxwell deserves many thanks from my kids and myself!!! (and a cold beer if he is close)

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@SBDOBRESCU, very nice testimonial and it gives us hope. My problem is mostly in the summer with air conditioning, but I will definitely be pursuing this solution.
I do have a question on the Smartsense temperatures. Based on my experience with Smartsense devices (motion and open/close), they only seem to be reporting temperature changes every hour. How did you get around that?

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Changing the reporting threshold from 1 degree, to .1 degree in the device configuration seems to fix that for the ST sensors.

See original post updated. I’ve added a “Project Timeline” that details some of the steps. I have tested the settings for a/c couple of days ago, and everything seemed to be working just as well,but I do expect some more adjustments will be needed when summer comes around.

This is very cool and would fix the biggest issue in my home… My only hesitation right now is $80/vent :smile:

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It was hard to swallow, and took a lot of convincing but it hit an all time high WAF!!!

It’s just money!, and you can make more of that…

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"Day 3 - 10

Modified device handler for the SmartSense Motion sensors to report on 0.1 temperature changes"

Can you share the modified device handler?

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On a related note, I have several IRIS contact sensors that I will be using just as temperature sensors. Can the device handler be modified for just temperature reporting and reporting at .1 degree. I’d like to get rid of the UI displaying the Open/close part.

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OP really makes me want these in my home… But sadly all the vents in my home are 2x14 =( and I Really don’t want to convert them… Especially in the custom reclaimed wood floor…

I’m sure my wife would get behind that logic :wink:

My master bedroom is freezing when compensating for the kitchen when we cook.

I was thinking of just adding smart vents in the master.

@damohabir Did you ever get a response on how to change the IRIS contact sensors to .1 reporting threshold? I need that info too!

See this:

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Where is the code is this? Can you share your device type? I tried but I could not find it in the code…

Thanks

We did an upstairs extension 14 years ago. We left the original heating system intact, added an AC to it, and added a second upstairs AC unit/zone. The upstairs AC also has one vent into the downstairs living room.

This has worked out beautifully. First off, the upstairs AC is usually the only one that needs to run. The house faces south and has no tree coverage, so the sun is fairly unrelenting in summer. The upstairs AC tends to offset most of that heat. It’s only on really hot days that the downstairs AC is on at all.

As for heating, the original design of the basement heating system did not account for the two additional rooms. Therefore, I can close vents strategically. There’s a heat vent in the basement that is closed except during really cold days when I have hobby-social gatherings there. The exercise room’s vent is almost always closed; again, it’s only open on very cold days. (And in summer. It’s open for AC.) And the office only needs heat or AC sporadically. That door stays closed, so the room has little impact on the rest of the house. Oh, and the people who owned the home prior turned a closed in back patio into a room, and extended the heat there too.

Anyway, the original heating system design really only accounts for about 60% of the existing house. So I am an ideal candidate for smart vents. I just have to decide whether many hundreds of dollars, plus hours of configuration and testing, are worth avoiding moving a vent lever when I walk into a room lol

Right here! :slight_smile:

https://raw.githubusercontent.com/sbdobrescu/SmartThings/master/SmartSense_MotionKV.groovy