View Full Version : Zone thermostats, Nest etc Advise?

25th Feb 2018, 21:48
My twisty dial analogue thermostats are on the blink, cutting out several degrees after the chosen setting, cutting in several degrees below, leading to erratic temperatures.

I'm thinking about upgrading the system.

Its a simple upstairs/downstairs split with a Honeywell digital programmer.

We've got fibre b/band so connectivity shouldn't be a problem.

The Missus has Siemens Home on her 'phone talking to ovens etc.

What are your experiences with Nest et al? all recommendations welcome.

Thanks in advance

25th Feb 2018, 23:18
Just been wiring up a "Learning" Nest.

The cooling and heating connections are easy if marked but there is a problem if that you only have a four wire connection, the one that is missing is the "Common". (Not all thermostats had five wire connections)

So, the nest then only charges the battery when the heating/cooling is running. Long periods of idle will cause the battery to run flat. (It can be manually charged from a Laptop USB connection to get it going but it's not ideal.

So the best way is to run the separate "Common" wire which will allow charging even if the Unit is not Heating/Cooling.

Lots of info on't t'internet.


25th Feb 2018, 23:23
We installed a Nest soon after they came out, about 6 years ago now. I'm very happy with it. We have a very simple system, heating only for a single zone. The original wiring was for a very simple on/off mechanical thermostat, which the Nest is very happy with.

It gives us heating that varies according to the time and the day of the week, plus the advantage of being able to adjust it remotely - for example to bring the heating back up 24 hours before returning, or to turn it down when you forget before you leave.

25th Feb 2018, 23:35
The Nest thermostat works great and looks great. You won't find a better looking thermostat than this one and it is very simple to install and setup. I looked at other manufacturers, like Honeywell and Siemens, and they do have thermos with similar capabilities, except for the learning bit, which you may not need or want.

For one home, ours is setup to control baseboard and underfloor hot water circulated heat. We have four zones, but only have the Nest on two - the other two are local zones for the master and guest bathroom's underfloor heating. Outfitting for zones can quickly get expensive using this one.

Our second (modest) home near the wilderness has LP gas forced air heat with a damper setup for zone control in the bedroom areas. Two Nest devices cover this house perfectly and as a bonus, they provide data about the house when we are not there. Sometimes family members and close friends will use the house, and it gives us feedback on when the dwelling is occupied. This house had a legacy heat setup and as ImageGear suggests, was missing that fifth wire. We had a man wire it so there was a constant power source available, which was necessary since we are not at this house as often as we would like.

Since we live in a temperate area, neither home has A/C, but I would imagine the things work perfectly fine when scheduling cooling as they do heating. Friends have admired them, but I have been told, often by the same crowd that eschews anything Apple, that other thermostats can do what Nest does and more, for less money.