Nest T stat help

[romex jockey]

I guess they're in vouge now, and everyone with a 'smart phone' wants them in their homes around here.

so here's their 'instructional video', from the packaging...>>

https://www.youtube.com/watch?time_continue=1&v=dHKD-9uI24I

There is no schematic , and i've a two wire 'end switch' oil burner

I'm under the impression constant 24V needs to be @ the stat, but have no clue as to how or which terminal would require it

Anyone else dealt with this?

any help appreciated

~RJ~

 

[hbiss]

Hate those d@#& things! They are made for consumers to DIY, that's why there are no wiring diagrams. They are supposed to auto configure themselves to whatever system the customer has and to whatever wiring is connected- kind of. If you have a heating/A/C system with dampers, good luck.

I tell anybody that asks me to connect one to call an HVAC guy.

-Hal

 

[romex jockey]

Yep, i'm quickly becoming an anti-fan Hal....

~RJ~

 

[Dennis Alwon]

I think you just connect the red and white terminals. I think there is a battery in it.

 

[Dennis Alwon]

He is a vid that says what I said to do when you have a 2 wire T-stat

https://www.youtube.com/watch?v=V2ElRkI6YF8

 

[al hildenbrand]

I'm under the impression constant 24V needs to be @ the stat, but have no clue as to how or which terminal would require it

Anyone else dealt with this?

Yup.

Nothing magical about it. It has a subbase with terminals. The are the usual R, W, G, Y, B. . .etc. and a "C" that is for the other side of the transformer. The existing two wires used by the oil burner will be R and W. You'll have to have a third wire. . .

Yes, the unit has a battery, rechargeable. . . but it is really good (from the risk of a call-back sense) to give it steady unswitched transformer power.

 

[hbiss]

Yeah, you just have a simple switching thermostat like the Honeywell Round with the mercury switch probably. See how smart that thing is, connect it and see what happens. Maybe it has a "power robbing" power option. (It puts a resistance across the white and red such that it isn't enough to pull in the control relay and runs off the voltage drop.)

-Hal

 

[romex jockey]

Ok, so it has a batt that can do a 2 wire , but needs a recharge

so a third wire from some 24V source? C-common R1+hot Rc=return to end switch?

the unit i'm confronted with has 10 terminations, vs. the 6 in Denny's vid.....


~RJ~

 

[al hildenbrand]

Ok, so it has a batt that can do a 2 wire , but needs a recharge

so a third wire from some 24V source? C-common R1+hot Rc=return to end switch?

the unit i'm confronted with has 10 terminations, vs. the 6 in Denny's vid.....


~RJ~

Rc is transformer power for the "cooling" - don't us it.

Look. Most of your 10 terminations are not used.

Use RH for the thermostat wire that comes from the transformer supply in the End Switch.

You'll have to examine the "End Switch" to determine how to get ahold of both sides of the thermostat supply transformer. Hopefully its rated output voltage is within the range needed to supply the charging / operating needs of the Nest. Some of the supply transformers in oil burner controls can be rather puny.

Use W1 to send switched power (from the transformer) to the relay, or whatever starts up the fire cycle of the oil burner.

Add a wire from the Nest C terminal to the "other side" of the transformer that is powering the relay, or whatever starts up the fire cycle of the oil burner.

 

[sparky1118]

You need to bring 24 volts to the t stat if you’re using power circulators. Just bring the c terminal to the t stat. If you have a 18/2 you are screwed. Get the Honeywell version they work so much better and are comparable to all heating systems


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[sparky1118]

Rc is transformer power for the "cooling" - don't us it.

Look. Most of your 10 terminations are not used.

Use RH for the thermostat wire that comes from the transformer supply in the End Switch.

You'll have to examine the "End Switch" to determine how to get ahold of both sides of the thermostat supply transformer. Hopefully its rated output voltage is within the range needed to supply the charging / operating needs of the Nest. Some of the supply transformers in oil burner controls can be rather puny.

Use W1 to send switched power (from the transformer) to the relay, or whatever starts up the fire cycle of the oil burner.

Add a wire from the Nest C terminal to the "other side" of the transformer that is powering the relay, or whatever starts up the fire cycle of the oil burner.

Didn’t see this post sorry


Sent from my iPhone using Tapatalk

 

[Sierrasparky]

You can add a 24v tranny and it will work. or add a c wire.

 

[hbiss]

You'll have to examine the "End Switch" to determine how to get ahold of both sides of the thermostat supply transformer. Hopefully its rated output voltage is within the range needed to supply the charging / operating needs of the Nest. Some of the supply transformers in oil burner controls can be rather puny.

Use W1 to send switched power (from the transformer) to the relay, or whatever starts up the fire cycle of the oil burner.

Add a wire from the Nest C terminal to the "other side" of the transformer that is powering the relay, or whatever starts up the fire cycle of the oil burner.

There almost never is a wire from the other side of the transformer and just as rare is a control or relay that even makes that terminal available. I installed Honeywell Vision Pro T8000 thermostats at my house several years ago and I had to install additional (unpowered) slave relays for each zone powered from a separate 24 volt transformer just so I could bring that "other side" to the T stats in order to keep the screens illuminated. Fortunately I ran more than two conductor thermostat wire when I roughed the T stat locations in many years ago. But you are not likely to find those T stats in residences.

So installing that piece of Millennial techno junk in especially and older house can be major work. The least they could do is provide wiring diagrams for somebody that actually has a brain and can make the decision as to whether it can be installed or not.

ETA: Found this on the Nest site

• [h=2]No common wire[/h] Nest Thermostats generally work without a common wire, but in some cases one may be required.
  
  

-Hal

 

[Sierrasparky]

There is nothing wrong with those thermostats ( other than owned by Google). There motion sensing is the best of any of these types.
I just don't like the spying Google does. Heck they paid Nest 3 million to buy the whole shebang.
Many digital thermostats require the C wire. You just deal with it. There are add a wire devices too.
This is not the end of the world.

 

[hbiss]

I just don't like the spying Google does. Heck they paid Nest 3 million to buy the whole shebang.

We haven't even touched on that. Connects to WiFi? What more needs to be said.

-Hal

 

[al hildenbrand]

Rc is transformer power for the "cooling" - don't us it.

Look. Most of your 10 terminations are not used.

Use RH for the thermostat wire that comes from the transformer supply in the End Switch.

You'll have to examine the "End Switch" to determine how to get ahold of both sides of the thermostat supply transformer. Hopefully its rated output voltage is within the range needed to supply the charging / operating needs of the Nest. Some of the supply transformers in oil burner controls can be rather puny.

Use W1 to send switched power (from the transformer) to the relay, or whatever starts up the fire cycle of the oil burner.

Add a wire from the Nest C terminal to the "other side" of the transformer that is powering the relay, or whatever starts up the fire cycle of the oil burner.

Sierra Sparky's suggestion for an transformer/relay is an excellent one. I don't share Hal's negativity.

 

[hbiss]

I don't share Hal's negativity.

Because I just don't see what the hype is all about. It's no better than a programmable thermostat as far as scheduling goes. But the techies don't want to be bothered programming it. I guess setting temperatures on the Nest when they want it to change isn't programming.

I totally don't see the functionality of the motion sensor. In my house the thermostats are in an upstairs bedroom for the 2nd floor zone and downstairs hallway for the first floor zone. People walk past them at random times all day. They can't "see" any other part of the house to detect if anyone is home. Maybe if the house were an open floor plan with the thermostat in a location that could see most of it... Besides, I have hydronic heat with cast iron radiators. Response is slow so simply adhering to a fixed daily schedule is the most energy efficient regardless of what Nest may think.

The Nest communicates with your cell to know (I guess through GPS) that you are away. Really? There are five people in my house. And Google probably keeps track of where you go.

You can control the Nest via an app on your cell. Who cares? Millennials who have their phones grafted to their hand, that's who.

Nope, I just don't see how it saves you anything over a regular programmable thermostat. Just another Dumb Home techie gadget.

-Hal

 

[JFletcher]

I noticed they have 10 terminals, presumably for some PTAC units that require 18/10 thermostat wire. I'd never seen more than six until about 10 years ago, when I was asked to provide the thermostat wire in a hotel. I never got the specs on the PTAC units, so I decline. The electrician ran 18/ 6, and had to go back and rewire it all.

The coolest feature about that unit is the included level. I don't have Hals negativity toward them, however I haven't had to install one yet. I do agree that they look pretty useless over a regular, programmable thermostat.

 

[Sierrasparky]

I have a builder who swears by them over the honeywell Lyric.
The motion sensing is learning. which anticipates your schedule. The thermostat also learns how long it takes to raise or lower the temp. Most who use it will claim that you are more comfortable with one, as the temp is more stable.
I would agree however you aint gonna get a goggle product like that in my home.

 

[hbiss]

Most who use it will claim that you are more comfortable with one, as the temp is more stable.

What kind of heating are they talking about? Forced air or hydro-air can be very uncomfortable due to it cycling- blowing hot air then shutting down trying to maintain temperature. I can see where tweaking the cycle time and fast response by the thermostat might minimize that. If you have radiant or cast iron the peaks and valleys are non existent. Pretty much smooth even heat. Baseboard convectors are somewhere in between.

-Hal