My opinion of NEST on steam

ChrisJ

So I decided to buy a Nest last night and give it a whirl on my steam system.  Currently using a VisionPro 8000 series set to 2 CPH.



The Nest has already been returned as right off the bat after updating it locked up once.  After that it complained my wiring (2 wires) had no continuity to one wire and yet the other wire was good.  How that could ever be possible is beyond me not to mention it did control the boiler.  I am running a new line to get a common at the stat but that is moot at this point.



The lock up combined with complaining about a missing wire and the overall feel of the Nest was enough to make me return it.  It seemed slow to respond to temperature change, I hated the fact you had to wave your hand an inch from the screen to get it to display anything.  The huge number it displays is the set point and the current room temp is tiny which also annoys me.  I want more information not less!



So, my hunt for a thermostat that works like my VP 8000 but will give me data logging and more control continues possibly to never be fulfilled.  The Honeywell 9000 series doesn't offer data logging so seems like a waste of time and money.

Today I will be running the new line so the VP 8000 will stay lit all of the time.  I like to see what the system is doing when I walk by. 



Although I did not use it near long enough to allow it to learn anything it seemed to allow way too wide of a temperature change to me.  My VP 8000 set to 2 CPH will maintain less than a 1 degree temperature swing.  The Nest was doing a 3 degree swing.  Perhaps this would have improved over time I cannot say.

Mark N

Control and Data Logging

Your VisionPro allows you to control the temp and the cycle rate, plus setback features. What else do you wish to control? What data are you looking to log with a data logger?

ChrisJ

Control and data

Not sure what else I wish to control. What can you offer? I suppose I wish I had an outdoor reset type system but that will never happen.



For data I just want to know when the boiler is on and when it's off over a period of a week or a month. Essentially what the Nest seems to do other than I don't want all of the other garbage it does.



I noticed the Honeywell Prestige + Redlink seem to do what I want but I doubt I could justify the price for just adding data logging. Actually, would be helpful if the log also tracked outdoor temperature as without it the data is probably useless.

ChrisJ

PLC

I am still considering using a PLC as well.

I'm just not sure how the entire thing gets put together.

Alan (California Radiant) Forbes

Low Down

Thanks for giving us the low down on the Nest thermostats.  I was considering purchasing two of them for my radiant system, but I don't want one that will lock up on me or only respond when I wave my hand in front of it.



Also, displaying the setpoint vs. the actual room temperature is a drag.  No way to change that in "settings"?

ChrisJ

Nope

It seemed to give very little options as far as customizing things.



The locking up is what scared me. That is the last thing I need especially if the system is on at the time.

Mark N

Data Logger

There are data loggers available that can record change of state. You can get a pretty good idea of how much your boiler ran by using the therms on your gas bill and factoring out non heating gas usage.

vaporvac

total time on?

So I assume you want to know the specific times of day your boiler is running because my older Honey programmable tells me total time "ON". I also think it only lasts for 24 hrs (or maybe a week). It's been so long since I've used it. I then check my gas usage daily, jot down the current outdoor temp and put it in my little log just to get a feel. It's actually interesting, but it would be nice to have system that does this automatically. I have remote on the meter, but it's not up and running yet. Maybe when it is, Duke will let us log on and check our usage daily.

Do you log your gas usage daily at all? Just wondering if you've seen a pattern now that you're using 2cph?

ChrisJ

Yep

I'd love to be able to open a graph and see when and how long the system ran vs the outside temperature.



I would have to make notes of what the gas meter says every morning and evening in order to log data usage so that will probably never happen.

Mark Eatherton

ENV...

I have a logic in my mountain home named ENV, by Climate Automation Systems.



http://climateautomationsystems.com/productoverview.html



It can stand on its head and spit wooden nickels. And it data logs as well. It uses a PC for running the system. You pay for the hardware, and they charge you for the number of "points" that you monitor and control.



I can call it up from any internet position, and either turn things up or down, or look at the data stored (I have it set to log every 5 minutes), and can see how long different things have been running.



The control sequence is only limited by your imagination. Which is pretty scary of you've ever seen my imagination.



The logic is also available from Rehau, as well as Mr. Pex, both resellers of the basic system.



I also tied the Lochinvar controls into the same PC, and using Logmein.com (free application) I can get into the PC, again from anywhere in the world with internet connectivity, and see what my boiler is actually doing, including fan speed, supply temp, return temp, flue temps, recent lock out issues, failed ignition attempts etc, etc.



The really cool thing about it is that if it has any "issues", it will send me an email. I know I've got a problem before it becomes a BIG issue, and it's saved my bacon numerous times so far.



Enjoy



ME

JohnNY

ENV

Hi Mark,

Do you know if it would be easy to move that system to different locations after some time?



In other words, I often think it would be a good idea to monitor a new install from a remote location but don't necessarily want to be responsible to for constant monitoring, unless I'm getting paid for it, of course.

There are lots of heating systems I install that I wind up popping in on a day later, a week later, a month later...



It would be nice to move a web-based monitoring system to new locations .

nicholas bonham-carter

If cell service is available......

Then set up a connection to the internet that way, and use a temporary wi-Fi thermostat, for the breaking period on the new system. Put all the components into a briefcase, and leave it on the job, running the new system.

Using the same sort of control for every new boiler trial run would make it easier to be familiar with the interpretation of all the information collected. A bonus would be the selling of a new thermostat as well.

The Ecobee seems to be adaptable to several different sorts of sensors, in the case of temporary jumping out a more complicated boiler control.--nbc

ChrisJ

Learning

Mark S,



I agree completely in regards to not giving the Nest any time to learn and I cannot really comment on how it functions that way. As you said, they are notorious for deciding what you should and shouldn't see.



To be fair, if my Honeywell ever locked up I'd ditch it just as fast.



What is interesting is a lot of reviews for the Nest V2 had the same complaints as me. Having to wave your hand right in front of it to get it to wake up and so on. Seems like the V1 was better in many ways.



I should also note the unit I had was running "Display 2.8" which I guess is the version of firmware. Seems to be the newest as I couldn't find info on anything higher than Display 2.6.



I looked at Ecobee but they seem to be the same deal as the Nest in regards to not many options and being "dumbed down" so to speak. Maybe I couldn't be more wrong but their website certainly doesn't say much and they seemed to be aimed at DIY just like Nest.





Can anyone say how Honeywell's Prestige series compares to the VP 8000? Is it any smarter or better in regards to how it would work on my steam system maintaining 1 temperature? Does it use weather forecasts to modify its behavior? I'm guessing it would behave identical but am curious.

nicholas bonham-carter

Weather predicting thermostats???

Since I have a rather low opinion of the possible accuracy of the local meteorologists, what would be the benefit of a thermostat relying on weather forecasting?

Surely indoor feedback is all they need.--NBC

ChrisJ

Weather forecasts

Since there are no outdoor reset type systems available for steam I would assume one that uses a local forecast would be better than nothing. I realize Tekmar has one but I think its a bit much for a single family home.



As far as what benefit, I would think it would help predict what length cycles to run in order to avoid overshoot. Even a 5-10F off reading from a local weather forecast would be better than absolutely nothing. No?

nicholas bonham-carter

Outdoor reset for steam

On hot water systems, there is an obvious benefit to outdoor reset: the variance of the loop temperature to suit the needed heat supply for the temperature difference between indoor, and outdoor.

For steam, I still have a hard time seeing the use of the Heatimer/Tekmar system of calculating run times according to the outside temperature. After all, the system still should have an indoor sensor(s), so as to have feedback. I think well placed sensors could do the job, even with a large building.--NBC

ChrisJ

Absolutely

I agree an indoor sensor is needed.

However, how does the thermostat determine system run time? My VP 8000 does fine as long as ambient doesn't change much. If it changes drastically which it has been it completely throws things off until the thermostat has time to readjust.



Please understand I am by no means a pro and have very little experience at this. There are many on here who know far more about it such as yourself. But I would think any system that cannot start and stop as fast as forced hot air could benefit from an outdoor reset type system. Perhaps more for comfort than fuel savings but I have to think there is a small amount of savings that could be had. Any reduction in overshoot should result in less fuel usage.



I would think it could also make setbacks more useful with steam as well. I have absolutely no problem with balance or pressure doing a 5 degree recovery even when the ambient is 10F. However I end up with a 3-5 degree overshoot if I do making it pointless.

Mark Eatherton

Oh sure...

The only caveat is that you MUST have solid internet connection. They sell one unit that has something like 32 inputs, either analog or digital. You strap sensors on whatever you want to monitor (can also use relays to convert from voltage to digital ON/OFF signal for pumps, gas valves etc)) and even a 0 to 1o VDC signals, set the recording sampling times, and let it rip. When you are completely done, you bag it all up, and move it to the next job. You'd have to use a DYN.DNS tracking tool (free) unless their ISP is a static IP.



Talk to Ron Antinori at ENV/CAS and he can tell you what you'd have to do. You will need a small dedicated PC, but those are cheap these days. I think I paid like $500.00 for my last one. And if you happen to be so lucky as to use a boiler manufacturer who has a place to be able to interconnect a PC with the operating system of the boiler, you can go in and look at it the same way I do with my Lochinvar, and even adjust/tweak parameters if need be. Save a LOT of man power, and parking ticket/gas fees for your operations . :-)



ME