Why smart thermostats don't always save you money

[ericmark]

BBC news report the report is interesting reading, where it is saying manual control can be better.

I am considering what to do with my useless Nest Gen 3, it is more of an ornament than a thermostat, as it does not connect to the TRV heads, and the remote temperature sensors have not been released for the European market, only works with USA model.

But what to replace it with, already have 9 electronic TRV heads, seems daft to just change for changing sake, and boiler does not modulate.

I followed the link Best Smart Controls dated 18/04/2020 and noted it says Nest works with Energenie TRV's, I know from bitter experience this is no longer the case, and when it did, it was wrong way around. We want to program the room schedule and for the boiler to fire up when required, not to have every room follow the wall thermostat schedule.

For me latent head recovery and modulating boiler control is not some thing I am interested in with an oil boiler. But in mothers old house I looked at the Worcester Bosch boiler and what would work with it, and realised although the more modern version could use Worcester Bosch Wave now replaced with EasyControl, there was no information about Bosch Smart TRVs. These it seems are £71 each, (seen at £55) not cheap, and use zigbee, but the Instructions say very little nothing about geofencing or door open detection etc. But at least now you can use TRV's electrical linked to boiler.

But the major problem is new products arrive, old ones removed, and finding out what works with what is not easy.

 

[Ltnman]

What is the payback period after the expense would be a key consideration.

 

[BlueLoo]

Read my history as to what i did with the install of a "Zero-Zone" system using the Wiser Drayton system.
Best thing i have ever done in the house. Works a dream.
I no longer have a need for individual thermostats as each radiator valve is independant.
I removed the zone valves, put E-TRVs on EVERY rad, Installed a diverter valve for the bypass and have never looked back.

Amazeballs.

 

[cdbe]

How can they possibly save you money? Surely you only put the heating on when you're absolutely freezing, and turn it off when you stop shivering?

Last year we had the heating on the timer and I would regularly come in and hear the boiler going when it wasn't really cold (probably could have benefited from geofencing or weather compensation or something), I'd sit there in my boxer's - those days are long gone. I'd burn the tado/nest etc if they'd produce some useful heat.

 

[mcprinter]

How can they possibly save you money? Surely you only put the heating on when you're absolutely freezing, and turn it off when you stop shivering?

Last year we had the heating on the timer and I would regularly come in and hear the boiler going when it wasn't really cold (probably could have benefited from geofencing or weather compensation or something), I'd sit there in my boxer's - those days are long gone. I'd burn the tado/nest etc if they'd produce some useful heat.

Wrong side of the Pennines?
How about comfort?

Have just fitted Wiser kit with 5 TRVs
Mrs works from home
Most of the House kept lowish during the day . Home office kept comfortable at 20.
5PM Lounge to temp. Office low/off.
No longer relying on a single stat in the hall to make other areas of the house comfortable.

 

[Mister Banks]

How can they possibly save you money? Surely you only put the heating on when you're absolutely freezing, and turn it off when you stop shivering?

Last year we had the heating on the timer and I would regularly come in and hear the boiler going when it wasn't really cold (probably could have benefited from geofencing or weather compensation or something), I'd sit there in my boxer's - those days are long gone. I'd burn the tado/nest etc if they'd produce some useful heat.

It’s not really just about saving money, people like gadgets to play with and now home automation is a thing these “smart” thermostats fit right in.

 

[Notch7]

my Thermostat has a dial, turn it till it clicks and the heating comes on.

that’s more than smart enough for me.

 

[ericmark]

It saves money as only heating rooms in use, but of course some people only have two rooms, I have 14 heated areas, not all rooms. Four are only heated when we have visitors.

I will admit there are problems with my heating. Hense the post, I also have a simple dial and turn it up when cold until it turns orange.

Geofencing did not work for me. Mothers house with gas the electronic TRV's worked well, but this house with oil, not so good.

 

[BlueLoo]

my Thermostat has a dial, turn it till it clicks and the heating comes on.

that’s more than smart enough for me.

Why not fit a light switch instead?

 

[ericmark]

Why not fit a light switch instead?

I have wondered, the TRV controls the temperature, so what we want is some thing to turn off boiler once all TRV's have closed.

I am sure one could fit a switch to the by-pass valve so once it lifts it switches off.

Switching on again a little more of a problem, but it could be a manual reset/start.

But the question is what is "Smart"? Would a system doing this be considered as "Smart"?

To my mind telemetry on it's own is not smart, yet it seems that is the only extra function of a smart meter.

 

[Mister Banks]

Isn't turning off the boiler what the receiver does once all smart TRV's have signalled they no longer need heat.

 

[ericmark]

Not quite, when they turn off, the by-pass valve lifts, hot water is returned without cooling, the boiler detects this, and turns at first down, then off.

However as the boiler cools it switches back on, even when room has not cooled. So it ends up cycling on/off every so often. The anti cycling software can reduce how often, but not stop it.

The linked TRV can in theroy control boiler, but my Energenie Mihome TRV's show on my PC target and current, and my wall thermostat (Nest Gen 3) is also controlled by my PC, so all it needs is some thing to link the two devices.

It may well be that the Google Nest Mini can link the two, not tried, but they do some times miss hear voice commands, turn off landing lights some times gets the reply landing fan unavailable. This does not matter even if fan was plugged in, but don't want central heating to fail.

 

[Mister Banks]

I think the Drayton Wiser and the tado TRV's communicate with the receiver/hub and if none are requesting heat the receiver/hub turns the boiler off. Hopefully someone with either system can confirm if this is correct.

 

[mcprinter]

I think the Drayton Wiser and the tado thermostats communicate with the receiver/hub and if none are requesting heat the receiver/hub turns the boiler off. Hopefully someone with either system can confirm if this is correct.

I have Wiser. This is correct.
Same principle as a wireless thermostat except you have multiple stats that can trigger the receiver/boiler.

 

[Mister Banks]

I have Wiser. This is correct.
Same principle as a wireless thermostat except you have multiple stats that can trigger the receiver/boiler.

I have edited my post to clarify I mean TRV's rather than just "thermostats", can you confirm the TRV's do communicate with the hub and this then turns the boiler off. Thanks