Can a smart vent system keep you comfy?

boy in room
© Alea Labs

Alea Labs is introducing the "smart vent 2.0", which again raises the questions we had about Smart Vent 1.0.

Alea Labs has introduced a new "smart vent" that "manages your home's airflow, moving air to the right rooms at the right time based on your temperature preferences, habits, and floor plan." Basically, you pop out your dumb vents and replace them with Alea's and in a few minutes,

Alea leverages 11 sensors and machine learning algorithms to understand the thermal characteristics of each room in your home, then it optimizes to your preferences taking into account everything that effects the air in the room.

This is not the first time we have written about smart vents; a few years ago when smart home stuff was all the rage, I was really dubious and wrote about Keen and Ecovent designs, noting that heating and cooling systems are not designed for this; when you close a vent, the blower pushes back and creates higher pressure, which increases leakage. Or not enough air will move and the cooling coils will turn into a block of ice.

Alea Labs published an article in Medium that gave eight reasons why you should invest in “Smart Vents” for your home.

They claim that their vents are smarter than the ones I wrote about earlier, and call out "myths", such as "people shouldn't tamper with professionally designed systems." In fact, they note correctly many systems are designed by rule of thumb, badly installed and often in need of adjustment. As for my worries about coils freezing or furnaces cracking, they claim that their vents monitor air flow and pressure and "are programmed to open the vents if there is any indication of crossing a risk threshold." As for Myth 6: “Supply and return ductwork systems should be balanced... This again assumes that typical HVAC systems are perfectly designed and balanced, which is often not the case, especially in existing homes." In summary, most systems are a mess and you are not going to make it any worse.

Alea Labs' founder Hamid Farzaneh tells Fast Company:

Alea Air’s smart vents close in rooms where you don’t want to direct the air flow, targeting only the rooms you do want to cool. This cools them faster and uses less energy. As a result, Farzaneh estimates that Alea Air will be able to lower users’ energy expenses by at least 20%.

The Alea vent also monitors humidity, air pressure and air quality, notably VOCs. It can talk to smart thermostats, and its batteries last longer because they use temperature differences for charging. There is a lot of interesting technology packed into these vents.

floor install vent© Alea Labs

However, there are a couple of things that pop out at me reading all this. The first is that I am very happy to have radiators instead of all these dumb ducts in most North American houses.

But more seriously, most of the reasons that Alea uses to justify their vents assume that the heating systems most people have are poorly designed by "rule of thumb" and poorly balanced. They note that even if the system is balanced, things change through the day, one side of the house may be in sun and get hotter and need more AC or heating.

All of which implies that their systems work best on a crappy HVAC system in an under-insulated and crappy house. This is something I noted before with the Nest thermostat: they have to work the hardest in worst houses. In a well insulated, say a Passivhaus design, a smart thermostat (and probably a smart vent) would be bored stupid.

Then they ask, "Why is the majority of homeowners or office workers unhappy with their lack of comfort? Why are most rooms either too hot or too cold at different times of a day?"

Here again, it is an argument I have made before -- it is because they don't understand what comfort is. As the Health and Safety executive in the UK noted,

The most commonly used indicator of thermal comfort is air temperature – it is easy to use and most people can relate to it. But although it is an important indicator to take into account, air temperature alone is neither a valid nor an accurate indicator of thermal comfort or thermal stress.

Physicist Allison Bailes, in his infamous article Naked people need building science, points out that temperature is not what makes us comfortable. The biggest factor is not the air temperature, but the building around you.

In your home, there are surfaces all around you, and they have a big effect on your comfort, whether you're in the raw or not. You're giving off heat, and so are they. If they're cooler than you, you lose heat. If they're warmer (think bonus room in summer), you gain heat. If you keep the air temperature at 70° F in winter, the closer your walls and windows are to that temperature, the more comfortable you'll be.

Engineer Robert Bean tells us that comfort is a state of mind.

It is the wonderfully coordinated processes between the nervous system and endocrine system which determines thermal comfort from the human factor perspective. No matter what you read in sales literature you simply cannot buy thermal comfort - you can only buy combinations of buildings and HVAC systems which if selected and coordinated properly can create the necessary conditions for your body to perceive thermal comfort.

This is why I worry that no matter how smart they are, a vent is not going to make you comfortable. It might adjust the temperature in the room, and it might even do it as effectively as Alea Labs says.

Product shot© Alea Labs

But in the end, a bit of smart tech won't make a significant difference. One has to look at the entire picture, all the factors that affect comfort. I suspect that a lot of people spending money on smart vents are going to be very disappointed. A vent, no matter how smart, cannot fix a crappy HVAC system installed in a crappy house.

Can a smart vent system keep you comfy?
Alea Labs is introducing the "smart vent 2.0", which again raises the questions we had about Smart Vent 1.0.

Related Content on Treehugger.com