Wifi Theromstats

I have an old home built in 1970s and I have a Peerless burner and Riello 40. I use oil for heat and hot water. I have baseboard heating throughout the house. I have a separate thermostat to control the AC unit. I have two floors and two zones. Currently, I am using Hunter thermostat which is not cost effective and I can’t control it on the phone or away from the home. These have to be programmed manually which is not always helpful or efficient.

I am thinking of Nest OR Ecobee 4. I know the benefits of each but I am not sure which is the BEST option for my home. I am thinking of Ecobee4 because it supports Apple Homekit. Besides that, I am looking for efficiency and reliability.

Do you have the C-wire to support the Ecobee? I know you can get a kit to do it even if you don’t, but I was scared off by that when I was unsure if I had the C-wire. I know several people who have the trickle powered Nest and works fine. I my self have the Ecobee3 because I ended up having the C-wire and think it is excellent as well as wanted the remote sensors (Nest didn’t have at the time). I don’t have a Nest so don’t know the ins and outs of integration to ST but I have Yves custom handler for the Ecobee and it works great. The stock ST DTH is less capable, but if you don’t need a lot, will probably be enough.

As for compatibility with your equipment, unsure on that.

Even if you don’t have a wired C-wire presently, check your thermostat cable bundle to see if you have unused wires. If you do, then it’s just a simple matter of taking an unused wire and wiring it to the C-wire terminal on the A/C unit.

I have the Nest thermostat. I like it in my two story house, but i don’t try to monitor other rooms like the ecobee sensors can. The Nest also needs a c wire for power. My wiring had the c wire tucked in the wall behind the original thermostat and the end on the A/C unit was just wrapped around the wires.

I thought the Nest could be wired without the c-wire also?

The Nest will work without the c wire it is suggested to connect it if possible.

From Nest website:
In some cases, you may experience odd heating or cooling behaviors after installing your Nest thermostat. Connecting a C wire to your Nest thermostat may help resolve the following issues:

  • Your system is making strange noises: chattering, stuttering, clicking or thumping - this can be caused by your system turning on and off rapidly
  • Heating or cooling is always on, and won’t turn off
  • Heating or cooling repeatedly turns on and off in a short period
  • You see a Delayed or Starts in message on your Nest thermostat’s screen (for example: “Heating is delayed for 2:30 mins”)
  • The system fan is always running or won’t turn on
  • The system fan turns on and off repeatedly in a short period

Nest Owners Not Exempt

The popular Nest thermostat claims to work without a C-wire, there are some caveats. Without a C-wire, the Nest gets its power from your heating or cooling system… assuming it’s running. When it’s not running, the Nest still needs to get power. The Nest will “pulse” the heat wire, turning on the furnace to pull a bit of power to keep itself going.

In some systems, this is unnoticeable, but in others, the furnace responds as if being told to turn on and then immediately off.

Read one frustrated Nest owner’s review of his experience with the “pulse” problem here.

Nest’s manufacturer updated its literature to warn that the Nest may be incompatible with some single cycle, no-C-wire systems, but the reality remains that outdated wiring is going to become more and more of a pain in the butt to deal with.

You don’t need to get a kit. Ecobees come with one already.

1 Like

No I don’t have the C wire. Most likely, I will have an electrician or HVAC make the run for me. I am thinking about Ecobee because of the room sensors and I want to incorporate it into Apple Homekit.

Why shell out that kind of money when you can successfully install and use the Ecobee without a C wire using the supplied power kit?

A much simpler and cheaper way would be to use Venstar - add a wire. It literally add’s an extra wire to your setup without having to install a full length wire (ingenious how it takes an existing wire and splits it into 2). Check out the link in the post below, it works great!

Check your wires. It may contain an extra unused wire tucked in the wall behind the old thermostat.

If’ it’s there, just pull that through the wall and connect to the c wire the thermostat. Then check the other end of the wire bundle. That same wire is most likely not connected to the A/C unit, so it will need to be connected to have power.

Edit: Saw @tpip’s post after posting this. Leaving mine in because repetition is good, lol. :slight_smile:

Make sure that you don’t have any unused wires in your bundle. I have seen installations where a c-wire is not wired, but there were unused wires in the bundle. If that’s the case, just connect one of your unused wires to the c terminal in your heat/ac unit and then you’ll have a c-wire at the thermostat.

No I don’t have any hidden wires in the walls behind the thermostat. I would never expect the previous owners (pre 2007) to think of it much less the technology wasn’t there.

I understand Ecobee could be connected with C wire OR supplied power kit. Obviously, I am going to do what is best for my situation and convenient.

Just to be clear, I’m not referring to hidden wires or anything extra the previous homeowner may have installed.

A thermostat cable is a single sheathed cable with a number of wires inside of the sheath. You may find that not all of the wires inside of that sheath are being used. Typically if this is the case, you’ll see the extra wire(s) coiled around the sheath not connected to anything. I’m suggesting if you have at least one of those, use it for the C-wire, saving you the trouble of fishing another wire from the stat to the furnace/ac.

Some installers use 8 conductor cables. I don’t think anything uses 8 conductors at the present.

1 Like

My house is pre-2007. The extra wire was hidden behind the wall, not connected on either end.

Builders will typically use the same wire bundle on every house installation. The homes that need the C wire initially will have it connected, the other homes will have it tucked away. Sometimes it’s hard to locate the unused wire as it can be tucked in the wall a few inches.

OK. I was just asking because you said…


…and was wondering why you would “most likely” pay an electrician/HVAC tech to run a C wire for you when one of the two candidates you listed made that unnecessary.