Home comfort on Ask This Old House

[Van Huskey]

The key to these systems is not the connectivity (that is just a small added bonus for some) it is the cost savings, convenience and near perfectly "balanced" system they offer. I have had versions of is in my last three homes with as many as 11 zones and as few as 7 only the current one is internet enabled. The only house it was added to I saw a decrease in heating of 15% and a decrease in cooling cost of near 30% and the rooms both up and down stairs stayed exactly where we wanted them. Europe has long been more "zoned" than we are in the US but they mainly do it with ductless systems. If you want all the rooms at similar temps and only have a one story house the savings may not be huge. One thing I like is my bathroom is set to get warmer just before I get up and go in to take a shower and our bedroom cools down right before we retire.

[Alan Rutherford]

I've been lurking on HVAC forums (fora?) hoping to learn something before our system gives up. The most important thing I've learned: right-sizing and installation are nearly everything. Also rare. You need the right amount of air moving through registers and returns and balanced pressures. Systems with variable-speed fans, 2-stage heat pumps and 2 zones are a serious challenge. Only on TV could 7 zones possibly work. Maybe it could if the heat source is circulating hot water or it's a super-sophisticated mini-split in every room but it's certainly not on my wish list.

We have a Nest wi-fi thermostat because it was given to us by the local power cooperative. I never found out why. It was a great conversation piece for about a week until the novelty wore off. Since then I don't let it on the internet except to program, which is easier that way. I've never had a reason for it and several reasons not to, the biggest being that I don't want Google (who owns Nest) or anyone with the ability to electronically snoop to know whether I'm home or not.

[Matt Meiser]

They are using pressure sensors at each vent and each room sensor to they stay within acceptable limits. What its doing is more akin to adjusting dampers to balance airflow than absolute control of the temperature in every room. The system will maintain enough airflow to prevent abnormally high pressure and the corresponding lack of airflow. Its not just a simple matter of running the HVAC and opening and closing registers to keep one room at 60 while another is 80.

[Brad Adams]

I run an HVAC business. That is the dumbest system you could ever install. You CANT run a system with only one room calling for heat or cooling. Most old duct systems are not sized properly to begin with. Alan pretty much summed it up. You can't push 1200 cfm through one boot that will maybe supply 110 cfm. That system is an ecm motor killer and compressor killer.

[Mel Fulks]

There are so many houses with only one return. We had one added upstairs in our cape cod and I can't imagine heating and cooling being any more even.

[Ken Combs]

I run an HVAC business. That is the dumbest system you could ever install. You CANT run a system with only one room calling for heat or cooling. Most old duct systems are not sized properly to begin with. Alan pretty much summed it up. You can't push 1200 cfm through one boot that will maybe supply 110 cfm. That system is an ecm motor killer and compressor killer.

I like the concept, but it needs to have a way to control motor speed/air handler output as well as variable compressor to eliminate that risk. I installed a mini-split in my addition that does all that but for just one room. They use a DC variable speed compressor and fan. works great.

But it would cost a lot more than just replacing the registers to get any real improvement.

[Matt Meiser]

It wouldn't run the system to heat or cool one room. Read about it...https://www.ecoventsystems.com/smart

[Ken Combs]

It wouldn't run the system to heat or cool one room. Read about it...https://www.ecoventsystems.com/smart

You're correct as the evovent doesn't control the system at all, except for run times or small temp changes. It changes the airflow distribution, but not the total airflow or heating/cooling BTU rate so is limited in what it can accomplish.

[Matt Meiser]

Incorrect.

How does Ecovent work with my thermostat?

Ecovent supports the award-winning, highly rated Sensi™ Wi-Fi Thermostat. We make small adjustments to your thermostat's target temperature, in order to get your heat or air conditioning to run for a slightly longer or shorter time, based on the temperature in every room of your home.

[Matt Meiser]

Our system is up and running as of this morning despite the incompetence of the installer. So far it seems good. I was briefly concerned about the fact I saw it running at least the fan with every vent I checked closed but it was explained to me over the phone that is part of a static pressure test on startup. After that it seems to be working well though it seems to have a little more hysteresis than a normal thermostat. I'm sure we'll be tweaking room temps for a couple weeks.

[Matt Meiser]

We've had the system running for 2 months now. Overall I'm pleased with it as our house does seem more comfortable. Its been a ridiculously warm January but December was bitter cold. Comparing average temperatures, days, and gas usage we are down a percent or two. I've been using the wall heater in the garage more but we've been using the fireplace less so its hard to definitely say anything. It may be difficult to compare summer as we are considering getting window film applied on the south and west facing sides of the house that dramatically reduces UV and infrared without affecting visible light too much.

We had an issue with our dehumidifier because their local contractor programmed the thermostat wrong. One of many issues I had with the installer and I've told our gas utility who is sponsoring the pilot that company will not be allowed in my home again. Like anything, the local installer can ruin the experience with an otherwise great product so I wouldn't hold that against them. I've made my displeasure there very clear.

It ate the first set of batteries pretty rapidly, a kind of expensive proposition considering we have 13 vents taking 4 AA batteries each. We'll see if the second set lasts longer. Long term I'd invest in rechargeable batteries but I'm not spending that just yet. A minor annoyance is that you have to open the app to get notification that the vent has lost communication. I probably only open the app to do a manual override once a week at the most. It appears that the vents open fully when the batteries are getting low to protect the system.

We had one issue, which has not repeated, where the system kept bumping up the thermostat setpoint until the house was way overheated. If that's anything but a fluke I'll take the system out right then.

Ecovent got bought out by another company and the support suffered as a result. I had sent a request about the issue above and never got a response until a few weeks ago when one of the founders contacted me. He was supposed to set up a time to discuss the issues I've seen but that hasn't happened. Honestly I have been to busy to follow up much too and I'm not integrating two companies so I'll give him a pass.

I sent them off a list of features I'd like to see added. One of those, the ability to schedule different heating vs cooling setpoints I consider a must-have coming up in 2-3 months here in Michigan. If that doesn't get implemented it may end up being the end of the experiment for us. Right now to switch between a schedule of summer temps and winter temps we'd have to rebuild the schedule. That could happen a few times mid to late spring and early to mid fall here. The other requests are around improved fan control for balancing temperatures and improving the notifications.

Right now I wouldn't spend $3K on the system, but it show's promise.

[roger wiegand]

We have the motorized dampers, but just run by regular thermostats (and not in every room). It seemed to be a less expensive alternative to a fully zoned system with multiple furnaces and AC compressors. The damper systems have been used in commercial settings forever, and so far, seem robust.

[Steve Peterson]

We have the motorized dampers, but just run by regular thermostats (and not in every room). It seemed to be a less expensive alternative to a fully zoned system with multiple furnaces and AC compressors. The damper systems have been used in commercial settings forever, and so far, seem robust.

We had a system with a single furnace and 4 thermostats in our old house. Each zone needs a thermostat to control the temperature. I can see how a cell phone would be able to control it also, but don't think it would be necessary.

It was nice to be able to set different temperatures in different areas of the house. The downside is that the furnace could be just finishing in one zone and then another zone starts up, so the furnace seems to run more often. An AC repair guy told us that it could eventually burn out the furnace motor because it was sized to feed air to the entire house, but often was only blowing air to 1/4 of the house.

Steve

[William Adams]

The thing is, this system won't run with only one damper open and all the others closed --- it would instead partially open all the dampers in the other rooms which are able to absorb the added heat, fully open the damper in the coldest room, then run until it can shut the system down adjusting dampers on the fly --- ideally it would never let the temperature get so out of whack.

[Ken Combs]

Incorrect.

I assume this was directed to me. And it is not incorrect. Their statement is that they change the target temp to run more or less. That has nothing to due with BTU delivery rate, just time.

I was referring to the functionality of later systems that can modify compressor and/or fan speeds based on total BTU needs. If that was included in the Ecovent repertoire, it would be truly good. But, one would have to already have a heat pump or a/c with that function, and be able to be externally controlled.