Nest thermostat, anyone using one?

[krystar]

Originally Posted by rick-l

Has anyone noticed a change in control schemes in all these new thermostats including just the setback thermostats?

Old method:

Hysteretic control - you would set the thermostat at 70 and the furnace would turn on when the temperature dropped 69 and turn of when it got to 71.

New method:

Pulse Width Modulation - when you set the thermostat to 70, 6 - 10 times an hour the thermostat checks the temperature and runs until it reaches the set point.

In my house with low heat loss sometimes the gas furnace will only run for 60 seconds. That can’t be efficient. Is this a conspiracy to sell more igniters with the service calls?

my thermostat has a temp swing setting. if u set target for 70F, set swing for 2F, it won't turn on heat until 68F, then heat until 70F. i think most modern programmable thermostats have that feature.

[look 171]

Originally Posted by Jim Richards

Aww man, you've completely crushed my dreams of spending $$$ to be able to fiddle with room temps on my iPhone while I'm sitting on the patio looking at the mountains, canyons and that tiny slice of ocean view.

When you are out sitting on the patio looking at the half naked women (yeah right, mountain and canyon views) you will often wonder why people need AC or heat around here.

[flipper35]

Originally Posted by rick-l

I think the reason for that is emergency heat (electricity) kicks on if the set point is more than 3 degrees different from interior temperature. I doubt that argument works in the summer.

Our estimated cooling costs for the summer was $32. I don't think messing with it in the summer will save us much either.

The electric elements do come on but you could set it to go up 2* and a short time later anoher 2* but we were told it doesn't save enough to make it worthwhile.

[Jim Richards]

Originally Posted by look 171

When you are out sitting on the patio looking at the half naked women (yeah right, mountain and canyon views) you will often wonder why people need AC or heat around here.

Now you're talkin'!

[rick-l]

Originally Posted by flipper35

Our estimated cooling costs for the summer was $32.

It only costs you $32 per month to cool your house in July and August???

It doesn't say where you live but is AC required at all? Geothermal is more efficient but you still have to run a compressor and fans.

[flipper35]

Originally Posted by rick-l

It only costs you $32 per month to cool your house in July and August???

It doesn't say where you live but is AC required at all? Geothermal is more efficient but you still have to run a compressor and fans.

Our estimated cooling cost for the year in SW WI is $32. The ground water is 48* and make our heating costs rise a bit but the cooling is good. It costs us more than the estimate because we run the house cooler than the estimate. I like cool in the summer. We went a summer without as our old central air unit got hit by lightning and ran the attic fan all summer. That was quite a bit more expensive than the geo unit. June/July/August mostly but May can get warm enough to use it a little.

[john70t]

Originally Posted by rick-l

In my house with low heat loss sometimes the gas furnace will only run for 60 seconds. That can’t be efficient.

It sure is not.
There may be drafts which make a huge difference.

My parents also had a furnace which was over-sized. That thing kicked on and off every 10 minutes and the bills were $400+/mo at 60deg.

[john70t]

I personally set the temp up to 70 at certain times(wake/dinner), then back down to 65-67.
It stays plenty warm for a long time and sweaters are still in fashion.
Girlfriend is a lazy smoker, and leaves the window open in the dead of winter

With forced air, the furnace runs until the air temp in that room reaches the set level.

What is not factored is the heat-soak of all the surfaces and objects in the house.

New electronic "efficiency" thermostats should be programable for a wider swing.
That is an easy feature to program in, but I've seen very few with this feature.

[techweenie]

For those of us paying over $100/mo for electricity and $30/mo. for gas, a smart thermostat of any kind is probably going to pay for itself in a few years and return dividends after that. If you're one of those who can remember to turn up/turn down your temps 365, you can save enough for a couple nice dinners out pretty quickly.

[sammyg2]

IMO simple is good.

A few years ago i finally switched from the dial type to a $16 digital non-programmable, but it ticks me off cause about once a year I gotta put two new AAA batteries in it.

[krystar]

if your thermostat wire is not 40+ years old, the...the C wire is wired for 18VAC

[masraum]

Originally Posted by ErVikingo

I just need one that circulates air every x minutes just to make sure air gets filtered without relying on teh fan to kick in for heating or cooling.

I have a thermostat like the one below, but it was a little cheaper (and filtrete brand which is rebranded radio thermostat hardware) when I bought mine a year or two ago. We have seen lower bills since we swapped. There is a smart phone app, but there is also a windows program. The windows program allows you to program the fan independently of the AC. It's not as pretty as the nest which is important to the missus, but when I bought mine it was more than $200 cheaper than the nest. Besides, the main things that I was looking for were the ability to program the thermostat from a PC and the ability to get the fan to periodically circulate the air in the house.

LockState WiFi Internet 7-Day Programmable Thermostat + Free iPhone App-LS-60i at The Home Depot

[campbellcj]

I put in two (dual zones) a few months ago - love them! We pay $350 to $1000+ a month for electricity and gas so the ROI should be there. And we do use the iPhone app feature all the time. It's kinda like a TV remote -- until you had one, you never realized how lame it was to not have one.

[look 171]

I don't understand the reason for adjusting the heat or AC all the time when you are away on that cell phone. is it because there isn't any thing to do.

[jwasbury]

I installed a Nest thermostat in my weekend/county house. The remote capability is very nice to be able to warm the house up a few hours in advance of our arrival. I can also check in on very cold nights to insure that the heating system is maintaining the set temperature. Gives peace of mind that everything is working ok and my pipes aren't going to freeze.

[john70t]

Originally Posted by campbellcj

We pay $350 to $1000+ a month for electricity and gas so the ROI should be there.

For that kind of pocket change I'd think about solar or ground loop for the long term costs.
Thermostat is a bandaid.

There's also the gas Bloom Box which looks interesting, but not sure if available for non-commercial application.

An energy audit is not too expensive, slow-fill foam insulation can be added into walls with minimal intrusion(small hole), and attic ventilation and light roof tiles make a big difference.

[RWebb]

The contractor that did my energy audit said if there was any insulation at all inside the wall, they could not add more (except by tearing the wall completely open.

Do you have more info on the slow-fill foam insulation?

[Moses]

Yep. I have three. LOVE them.

Love love love my nest !!!!

[john70t]

Randy, I should have typed slow-rise.
Basically the same open cell stuff but with a slower reaction time to not push out the drywall.
They drill a series of small holes (1/4-1/2" I think) and start at the bottom.
Two chemicals start as liquid, and turn into foam.
All excess comes out the holes.
AFAIK, was told it can be used with existing batt insulation. The foam just seals any gaps with the fiberglass settling.

I just looked at a finished basement bathroom (cold Mich) where paint was sagging off the drywall. There had been a fixed slow shower leak, but I suspected there was also an air gap at the top, and cold air was creating condensation inside that wall. The wall with sagging paint felt much colder to the touch than the other without problems.

[RWebb]

thx, I will look into that