Smart Thermostat or Alternative?

MRGANNET

Hi all, looking for a bit of advice as whilst I'm looking at things like Hive and Nest and their fantastic marketing, I'm really not sure if they are what I'm after.

We live in a 4 bedroom house with a boiler/hot water storage tank system. There is a programmer (Drayton Tempus 7) which is used to set timings for the heating and hot water coming on and the radiators have standard thermostat valve heads.

Obviously at the moment when the heating is on, it is on in every room where the valves are on, and I find myself running about a fair bit at the moment turning valves on and off, and up and down to try and get the right temperatures in different rooms we use at different times of the day. What I'd like to have is something which automates this process a little more.

What are my options for this? Basically over the the winter, I'd primarily like to have heat in our sunroom anc kitchen in the morning, lounge in the afternoon and then upstairs bedrooms in the evening and at a lower level overnight. We have a new baby so having better control over maintaining the right temperatures in the right rooms would be very useful.

Tom99

[FONT=Verdana, sans-serif]You need some sort of zone control. Easy if you were installing a new system but harder to retofit.[/FONT]
[FONT=Verdana, sans-serif]You could look at smart TRVs something like this:[/FONT]
[FONT=Verdana, sans-serif]https://www.screwfix.com/p/energenie-mihome-radiator-valve-kit/5669h[/FONT]
[FONT=Verdana, sans-serif]The are loads of similar stuff around.[/FONT]
[FONT=Verdana, sans-serif]Or work out your plumbing route to see if you can create a zone. For example if all the bedrooms are fed from the same flow [/FONT][FONT=Verdana, sans-serif]or[/FONT][FONT=Verdana, sans-serif] return then you could insert a valve controlled by its own programmable stat.[/FONT]

System

Tom99 wrote: »

[FONT=Verdana, sans-serif]You need some sort of zone control. Easy if you were installing a new system but harder to retofit.[/FONT]
[FONT=Verdana, sans-serif]You could look at smart TRVs something like this:[/FONT]
[FONT=Verdana, sans-serif]https://www.screwfix.com/p/energenie-mihome-radiator-valve-kit/5669h[/FONT]
[FONT=Verdana, sans-serif]The are loads of similar stuff around.[/FONT]
[FONT=Verdana, sans-serif]Or work out your plumbing route to see if you can create a zone. For example if all the bedrooms are fed from the same flow [/FONT][FONT=Verdana, sans-serif]or[/FONT][FONT=Verdana, sans-serif] return then you could insert a valve controlled by its own programmable stat.[/FONT]

I was a Honeywell Evohome user for 4 years. We sold our old property in July. If you are looking for convenience, then some form of zoning system is the best way forward. However, do not expect any of these systems to be 'fit and forget'. Wireless controls come with wifi issues which can prove to be frustrating. Also, the savings associated with these types of controls are, at best, debatable.

For example, an Evohome system with 12 zones, with a modern boiler connected via an Opentherm Bridge has a quoted ErP saving of 8%. Unfortunately, as I found out, for EPC purposes, ErPs are ignored. The EPC process will treat a property as having two thermostats (zones) only with a 1 to 2% saving. Why - because there is little objective scientific evidence that smart controls actually produce savings.

So what are the pros of zoning. Firstly, you can have the control that you are seeking which includes scheduling and IFTTT/GeoFencing. Zones can be set at different temperatures and times. Comfort levels in the rooms that you actually use can be improved.

The cons though are worth thinking about. Not all smart controls have built in frost protection. Evohome does: in the event of a comms loss, the boiler will cycle. Electric TRVs are expensive and can be noisy: not everyone is able to tolerate the frequent whirring in bedrooms etc. The siting of components can be tricky. It took my installer nearly 6 months to site the two BDRs (boiler demand relays) to stop the frequent loss of comms that I was getting.

Finally, most modern condensing boilers are designed to get a property up to temperature and then keep it there. Keeping it there usually keeps the boiler in a condensing mode. By monitoring gas flow every 15 minutes, I had the evidence to show that fiddling with zones was actually using more gas than it was saving. This is down to the 'fuzzy logic' that manufacturers build into their systems. If, say, a family member comes home from school and goes up to his/her bedroom and doesn't like the scheduled zone temperature and adjusts it by more than 1.5 to 2C, then with Evohome as an example, the boiler will go to maximum flow temperature until the zone is within its set temperature range. To put this into context, we could go out for 4 hours on a cold day and turn Evohome down to an Economy setting across the house (all set temperatures - 3). Turning it back on to its normal settings would actually use more gas than we saved.

This link is worth a look:

https://www.automatedhome.co.uk/reviews/drayton-wiser-smart-heating-controls-review-part-4-1-year-older-much-wiser.html

there is also a smart heating forum on the site.

paul1964mccarthy

I use the Honeywell Evohome. I have every room at the temperature I want, when I want.
I have no idea if it saves money, although my consumption is way less than the average for the age/size of house.
I would never go back to manual TRV's.