Will Smart Raiator Thermostats help reduce my heating bills, are they worth it?

BenEdwards

So a bit of background.  I have a Baxi Back Boiler, so my first thought is that turning radiators on/off or setting the termostats lower will make no diference (I've been told by various plumers, including one who is a frend, they all the traditional alegid thermostats are good for is turning radiators off or on).

But wondering if using Smart Radiator Switches will help significantly reduce my heating bill.  I would probably use a seperate smart termomiter with them.

The cost of the smart radiator switches is around £40 (whitch is not significantly more than the replacement traditional ones I had to get recently) and the smart thermostats are around £15.

Thoughts?

MultiFuelBurner

Needs moving to the energy forum

ThisIsWeird

To answer your Q, it's 'yes'.

It should be a statement of the bleedin' obvious that if you have fewer radiators running, you will consume less gas. So you either run around the house turning the valves up and down as required, or you just - wastefully - keep heating the whole house.

Smart valves come into their own with rooms that only require heating at certain times, of which bedrooms are probably the best example. These generally only need a bit of heat a short while before bedtime, and first thing in the morning. You may also want a lower level of heat all night, tho' that's why gawd gave us duvets.

So, how do you currently control the heat in your bedrooms? 

[Deleted User]

ThisIsWeird said:

To answer your Q, it's 'yes'.

It should be a statement of the bleedin' obvious that if you have fewer radiators running, you will consume less gas. So you either run around the house turning the valves up and down as required, or you just - wastefully - keep heating the whole house.

Smart valves come into their own with rooms that only require heating at certain times, of which bedrooms are probably the best example. These generally only need a bit of heat a short while before bedtime, and first thing in the morning. You may also want a lower level of heat all night, tho' that's why gawd gave us duvets.

So, how do you currently control the heat in your bedrooms? 

I beg to differ. Smart TRVs offer no additional savings over standard TRVs. They just offer more owner convenience at a much higher procurement cost. If there were significant additional energy savings to be made, smart TRVs would be made mandatory for new builds which is not the case.

The downside of shutting off too many rooms is that you end up with an over-sized and inefficient boiler that rarely condenses and continually cycles. I have a 4 bed home with 2 heating zone valves and manual TRVs. I leave the unused rooms set at 15C and the rest at 20C. Our gas usage for the past 12 months has been 4481kWh.

FreeBear

[Deleted User] said:

ThisIsWeird said:

To answer your Q, it's 'yes'.

It should be a statement of the bleedin' obvious that if you have fewer radiators running, you will consume less gas. So you either run around the house turning the valves up and down as required, or you just - wastefully - keep heating the whole house.

Smart valves come into their own with rooms that only require heating at certain times, of which bedrooms are probably the best example. These generally only need a bit of heat a short while before bedtime, and first thing in the morning. You may also want a lower level of heat all night, tho' that's why gawd gave us duvets.

So, how do you currently control the heat in your bedrooms? 

I beg to differ. Smart TRVs offer no additional savings over standard TRVs. They just offer more owner convenience at a much higher procurement cost. If there were significant additional energy savings to be made, smart TRVs would be made mandatory for new builds which is not the case.

The downside of shutting off too many rooms is that you end up with an over-sized and inefficient boiler that rarely condenses and continually cycles. I have a 4 bed home with 2 heating zone valves and manual TRVs. I leave the unused rooms set at 15C and the rest at 20C. Our gas usage for the past 12 months has been 4481kWh.

The OP has a Baxi back boiler, so it won't be condensing (unless it is a BBU 15 HE). Have (had) an ancient Baxi here, and I would agree that smart TRVs will not make for any significant savings over regular TRVs. A couple of things that will save gas though is to shut off the gas during the summer - The pilot light will be using something in the region of 2000KWh each year. Fit a smarter control system such as a Drayton Wiser that allows for different temperatures throughout the course of the day - Potentially, 10-15% saving there.

I've gone from an annual gas consumption of 8000KWh with the Baxi down to under 4000KWh with a smart control, regular TRVs on most radiators, and shutting the gas off during the summer. Due to circumstances beyond my control, having a new combi boiler fitted next month, and am replumbing the heating system & DHW in preparation. With the addition of some new radiators, I'm hoping gas consumption will remain under 4000KWh p.a..

[Deleted User]

FreeBear said:

[Deleted User] said:

ThisIsWeird said:

To answer your Q, it's 'yes'.

It should be a statement of the bleedin' obvious that if you have fewer radiators running, you will consume less gas. So you either run around the house turning the valves up and down as required, or you just - wastefully - keep heating the whole house.

Smart valves come into their own with rooms that only require heating at certain times, of which bedrooms are probably the best example. These generally only need a bit of heat a short while before bedtime, and first thing in the morning. You may also want a lower level of heat all night, tho' that's why gawd gave us duvets.

So, how do you currently control the heat in your bedrooms? 

I beg to differ. Smart TRVs offer no additional savings over standard TRVs. They just offer more owner convenience at a much higher procurement cost. If there were significant additional energy savings to be made, smart TRVs would be made mandatory for new builds which is not the case.

The downside of shutting off too many rooms is that you end up with an over-sized and inefficient boiler that rarely condenses and continually cycles. I have a 4 bed home with 2 heating zone valves and manual TRVs. I leave the unused rooms set at 15C and the rest at 20C. Our gas usage for the past 12 months has been 4481kWh.

The OP has a Baxi back boiler, so it won't be condensing (unless it is a BBU 15 HE). Have (had) an ancient Baxi here, and I would agree that smart TRVs will not make for any significant savings over regular TRVs. A couple of things that will save gas though is to shut off the gas during the summer - The pilot light will be using something in the region of 2000KWh each year. Fit a smarter control system such as a Drayton Wiser that allows for different temperatures throughout the course of the day - Potentially, 10-15% saving there.

I've gone from an annual gas consumption of 8000KWh with the Baxi down to under 4000KWh with a smart control, regular TRVs on most radiators, and shutting the gas off during the summer. Due to circumstances beyond my control, having a new combi boiler fitted next month, and am replumbing the heating system & DHW in preparation. With the addition of some new radiators, I'm hoping gas consumption will remain under 4000KWh p.a..

Go for Opentherm control if you can. It is mandated in The Netherlands. The best analogy is someone driving across London with traffic lights varying from go to stop. Opentherm cleverly modulates the boiler output to try to get you across London with all the lights on green! That is, it reduces boiler cycling than enhances efficiency and extends boiler life.

doodling

Hi,

Smart TRVs achieve the best savings where:
1. Different rooms are used at significantly different times with differing temperature requirements.
2. The house is sufficiently large that different temperatures in different rooms are possible and practical.
3. The house is relatively poorly insulated (or more accurately there is only a small difference in performance between the insulation from room to outside and the "insulation" between rooms).
4. People actually keep doors closed so that different temperatures in different rooms can actually be achieved.

Most smaller or modern houses don't fit these criteria very well.  If you have something like a large Victorian house with 4+ bedrooms then yes, I would recommend them.  Ordinary TRVs will give you a lot of the benefit, you already have those so the gains will probably be marginal.

As others have noted, if the boiler has a pilot light then this will be costing you fair bit over the summer and a boiler replacement would probably pay for itself relatively quickly.

ThisIsWeird

[Deleted User] said:

ThisIsWeird said:

To answer your Q, it's 'yes'.

It should be a statement of the bleedin' obvious that if you have fewer radiators running, you will consume less gas. So you either run around the house turning the valves up and down as required, or you just - wastefully - keep heating the whole house.

Smart valves come into their own with rooms that only require heating at certain times, of which bedrooms are probably the best example. These generally only need a bit of heat a short while before bedtime, and first thing in the morning. You may also want a lower level of heat all night, tho' that's why gawd gave us duvets.

So, how do you currently control the heat in your bedrooms? 

I beg to differ. Smart TRVs offer no additional savings over standard TRVs. They just offer more owner convenience at a much higher procurement cost. If there were significant additional energy savings to be made, smart TRVs would be made mandatory for new builds which is not the case.

The downside of shutting off too many rooms is that you end up with an over-sized and inefficient boiler that rarely condenses and continually cycles. I have a 4 bed home with 2 heating zone valves and manual TRVs. I leave the unused rooms set at 15C and the rest at 20C. Our gas usage for the past 12 months has been 4481kWh.

I agree with pretty much everything you say. Which kind of highlights the contrariness of begging to differ.

Absolutely, if the homeowner is happy to scurry around turning their manual or TRV controls up, down and off to suit demand, then Smart valves are pretty pointless; they are all about doing this for you, so it actually happens. 

Ditto with Prog Stats. Folk often ask how they save energy and money. And the answer is, by turning down the room stat when the occupant is too bone idle to do so.

Yes, shutting off a number of rads will tend to have a boiler like the OP's 'cycling' more than is desirable. But what's the alternative - heating the whole house unnecessarily? 

ThisIsWeird

doodling said:

Hi,

Smart TRVs achieve the best savings where:
1. Different rooms are used at significantly different times with differing temperature requirements.
2. The house is sufficiently large that different temperatures in different rooms are possible and practical.
3. The house is relatively poorly insulated (or more accurately there is only a small difference in performance between the insulation from room to outside and the "insulation" between rooms).
4. People actually keep doors closed so that different temperatures in different rooms can actually be achieved.

Most smaller or modern houses don't fit these criteria very well.  If you have something like a large Victorian house with 4+ bedrooms then yes, I would recommend them.  Ordinary TRVs will give you a lot of the benefit, you already have those so the gains will probably be marginal.

As others have noted, if the boiler has a pilot light then this will be costing you fair bit over the summer and a boiler replacement would probably pay for itself relatively quickly.

To a degree. My house is neither of your chosen options. It's a 3-bed, 1930's, reasonably well insulated - but pants by current standards - extended bungalow.

I added one Hive Smart valve to our bedroom rad so's it would come on a half hour before bedtime, and ditto in the morning. It does the intended job.

Rob5342

We have them in a few rooms and they are great for comfort and convenince. We have the bedrooms set to 18 most of the time so they are cool to sleep in but they come up to 21 for an hour in the morning and even so it's nice and warm when we get up and go to bed. We have the lounge set to 21 during the day but it goes down to 18 overnight.

Alnat1

Rob5342 said:

We have them in a few rooms and they are great for comfort and convenince. We have the bedrooms set to 18 most of the time so they are cool to sleep in but they come up to 21 for an hour in the morning and even so it's nice and warm when we get up and go to bed. We have the lounge set to 21 during the day but it goes down to 18 overnight.

18C is cool to sleep in? I'd personally want to open the window if the bedroom was that warm or I'd be awake all night.

Lounge is 17.5C in the day, bedrooms around 14-15C. Heating off overnight unless below 0C outside, then it stays on with lounge thermostat at 14.5C which will let the bedroom heat up a bit now and then.