Nest thermostats

delta T

Just wondering if anyone has used these, installed these, worked on a system with these, etc. I have not. With the right system I could see it working well, however I don't know how smart they actually are. Obviously there is the benefit of being able to see and control the temp in your house remotely, but my question is more centered on how good the algorithm actually is.



My feel is that the "learning" capability would be useful with a FAGF but I wonder if it would start to try and short cycle a high efficiency low temp radiant system given the slower reaction time of a system like that. I have always felt that a modern radiant system like that in a tight highly insulated house works best without trying to change the temp too much.



Any thoughts?



<a href="https://nest.com/thermostat/life-with-nest-thermostat/">https://nest.com/thermostat/life-with-nest-thermostat/</a>

Gordy

Answered

Your own question. For the cost of a nest I think it's an apple/ google trinket for the wall for the apple lovers.

Robert O'Brien

3.2 Billion?

Nest was sold yesterday for $3,200,000,000,not bad for a trinket ! And by far more than the combined value of every boiler manufacturer in the USA. Scoff at new technology at your own peril

Jamie Hall

As I have noted elsewhere...

Google does not buy something it doesn't need and expect to make money out of.  Google makes money by selling personal information to advertisers -- not selling hardware; that's incidental.



The Nest can, though its internet connection, report on what the temperature in your house is, whether the house is occupied, what you have the thermostat set at, as well as fundamentals such as what type of heat you have, what type of fuel you use, etc. etc. etc.



Do you really want all that information integrated into Google's really superb data crunching machinery and sold to all and sundry?



If you don't think that Google is going to do that, I have a really nice bridge for sale, sightly used but with good potential, in New York...

delta T

Hmmm

Didn't hear that google bought them out until last night, the data mining thing is kind of scary. I think that colors my opinion of them enough. don't want google selling my customer's info. Thanks for the opinions all

SWEI

The Nest

like all other conventional thermostats, is only capable of telling the system two things:  "I'm too hot" or "I'm too cold."  You can wrap all the intelligence you want around that, but it will not change the simple fact that the interface to the heating system is a one-bit, one-tenth of one Hertz channel.



The Nest achieves savings by setback, which is fundamentally at odds with modern radiant heating designs.

Bart Vaio

Set back at odds with modern design?

How is setback at odds with modern radiant designs? I'll agree ODR slows system response time a bit but modern design I.e. Zoning, Warmboard, quick trac, heat ply and Gypcrete work quite well with setback. As opposed to old traditional designs like high mass slab on grade which do not benefit much from setback without comfort issues. Nest also has the ability of remote monitoring and adjustment which makes it great for vacation homes. We use them on quite a few projects and I have never had a complaint, easier to program than any other stat on the market for sure.. Sure it is brought to you by the creators of the Ipad and IPhone but is that bad? Those innovations seem to have gained a bit of popularity.

djohn

ecobee

Consider Ecobee as a way better choice over Nest. It does extensive reporting, can monitor your temps (Azel + sensor module), usage, etc. Can have additional sensors added, like moisture sensor, humidity sensor, slab sensor, etc.



I am currently building a 3 zone system with 3 Ecobees. I think another member here had a really neat install with this thermostat.

Eastman

Dear Apple

To counter this new google front, I suggest you buy Tekmar.

Gordy

Inflated

Apple value is 3.2 billion. If nest is a money maker why did Apple sell it?



Still say its a trinket a thermostat that Apple heads think they have to have to go with all their other apple gear.



Common really look at it . It's a t87 housing that went digital with a couple extras. Google just wants the internet information. Think about it. Google might set your thermostat back for you .....like it or not.

Jean-David Beyer

How is setback at odds with modern radiant designs?

I have a mod-con with two heating zones. The big one is a radiant slab at grade and if I change the temperature setting, it takes 4 to 8 hours to notice a small temperature change, and about 24 hours to stabilize at the new setting. And that for only a small change. When Sandy cut off my power for 6 1/2 days, the house dropped about 11 degrees (F). After about a day, I decided it would take a week to recover, so I temporarily changed the setback to run 10F warmer water into the slab. It still took over 24 more hours to recover. Of course, this is not surprising.



My other zone is fin-tube baseboard. It originally had 3 feet of baseboard in each of two rooms. When I had the mod-con installed, I had the baseboard replaced with 14 feet of Slant/Fin Baseline 2000 put into those rooms. I originally had 4 degrees of setback there, but it could not really recover from that. I enabled the boost feature that raised the supply temperature 10F if it had not recovered in two hours, but even with that, it would take about 4 hours to recover. I reduced the setback to 2F, but it still took too long. Now the boiler does have the capacity to heat those rooms up very fast, but only if I sacrifice the condensing. So I stopped doing setback there too.



I conclude that if your reset curve is as tight as possible, consistent with supplying enough heat to the rooms, that there is then not enough to recover from setback.  And for my system, even the 10F boost will not be enough to recover from a meaningful setback in a reasonable time.

Alan (California Radiant) Forbes

Forget Google

and build your own Nest thermostat:



http://grist.org/list/how-to-build-a-nest-smart-thermostat/?utm_source=newsletter&utm_medium=email&utm_term=Daily%2520Jan%252023&utm_campaign=daily

Harvey Ramer

I second that.

EcoBee is my favorite stat. It gives you excellent control over your equipment.



Harvey

Bart Vaio

PDR vs. Setback

That is the question, Yes? If your ODR is set to thin you will never recover from a setback, but where is the sweet spot for ODR and do we benefit from fluid temps that low or is it sacrificing our comfort and our ability to turn off the heat for a few hours only to run a 1/2 percent more efficient when you are firing. Hmmmmmmmm.

Gordy

Bart if ODR

And boiler size is dialed in then there is the efficiency. Save the set back for vacations, or out of town for the weekend. What's really gained in a set back of a few hours only to bring the MRT down then back up again like a yo yo.



I really don't know what you mean by the ODR being so thin your sacrificing comfort by to low of temps unless your referring to when we get these polar,vortexes?

Gordy

Bart if ODR

And boiler size is dialed in then there is the efficiency. Save the set back for vacations, or out of town for the weekend. What's really gained in a set back of a few hours only to bring the MRT down then back up again like a yo yo.



I really don't know what you mean by the ODR being so thin your sacrificing comfort by to low of temps unless your referring to when we get these polar,vortexes?

Bart Vaio

Do you agree?

Do you agree that a home at a 68 degree setpoint is less expensive to heat annually than a home with a 74 degree setpoint? If we setback our home for sleeping from 9pm to 7am from 72 down to 60 are you saying that does not save energy? Doesnt that make our 24hr average temp setting 67? Our house is zoned and our kids room (140 sq ft) maintains 70 deg all night while 2400sq. ft is set back to 60. We have a warmboard system and it takes about 35 minutes to come up those 12 degrees in the morning. Heat loss is highest at night when the temp is lowest and the diffence between indoor and outdoor space is highest right? Our energy codes in California requires setback thermostats for all residential and commercial installations, why does that efficiency not apply to radiant? Setback recovery is hampered by a reset curve that is correctly set as recovery is very slow from a deeper setback due to the very conservative and efficent fluid temps, Lochinvar has programming logic for short term temp boost above the curve if the boiler is not satisfied in a certain amount of time which helps. We are on propane at 2.75/ gal so we do everything we can to conserve energy and maintain comfort. I also like the Buderus RC 35 control for the Domestic and Heating schedule programming.

Gordy

Bart

If you take your heat loss program, and plug in a different indoor temp I think you will find the savings are not all that extreme.



In my case lowering the indoor temp from 72 to 62 degrees yields an overall 10000 bots less than the heat loss at 72. This is at a design day condition which is about 1% of the season.



If you set back for 6 hours each day by that 10 degrees that's 60000 btus for the 6 hour set back period. multiply by 30 days average monthly that is 1800000 btus or if your on NG 18 therms which equates to less than 8.00 a month. Or a whopping 48.00 for a 6 month heating season. A price I'm willing to pay for an MRT that's not lowered in the mornings.



Now does set back save? Technically yes. How much...not much. Remember i did the math off of a design day scenario which is not the case 99% of the heating season! and my house is a plain 50s construction ranch.



One other thing is the savings is even a bit less when you figure the boost temps to come out of setback verses maintaining your original set point. Even after set point is reached the houses MRT will lag the thermostat setting.



Obviously a user of oil, or LP fuel types would reap more savings. 2.75 a gal for propane verse .45 cents a therm for NG. Your paying 3.02 for the same amount of btu content as a therm of NG. Or 571 % more than myself. If I were on that fuel at that price I would save 274.08 a season or 45 bucks a month.



I think it's a case by case according to fuel costs. 10 degree set back is pretty drastic, and most well insulated homes would be hard pressed to lose that much temp in 6 hours.

VictoriaEnergy

Reallly Google,...Really?

The Nest has all the gadgety coolness of an iPhone. 



But after that it's overpriced and under- performer in terms of reliability.  It has nothing to make it an exclusive or patent protected "game changer" in our industry.



I think Google made a mistake.   (I suspect it was the only thermostat anyone remembers seeing at the CES show...so of course they had to buy it.)

Gordy

Motorola

Goggle bought Motorola for 12.4 billion in July of 2012, and has lost 1.4 billion on that bet to date.