Turn boiler down or room stat?

[toonburner]

I have searched this and couldn't find the answer, apologies if I've missed it. Is it better (cheaper) to turn down the boiler or to turn down the room thermostat?
The boiler is a Potterton Suprima, 12 years old.The room stat is in the hall and we usually use this to regulate the temperature but recently someone told me I should turn down the boiler instead.
I'm finding it difficult to work out if it's costing me more money doing it this way because of all the price increases. I have a 4 bedroom detached house with double glazing,cavity wall insulation and full depth loft insulation and my bills are £1200 p.a.
Any help would be appreciated.

 

[ALEC1]

on this boiler it doesn't really matter as its hopelessly inefficient anyway, turn it down too low and it will cause backend condensation. so in the respect turn the room stat down to save a bit..

modern boilers with a certain type of controls do indeed lower the boiler temperature when you lower the room temperature...

 

[dcawkwell]

Turning down the wall thermostat will save regardless of boiler setting.

Your suprima is a non modulating boiler therefore it is on or off.
A boiler is most efficient when running for longest. Therefore
in this instance to keep the boiler running for longest
I would say a higher setting of the boiler that will heat the rooms
and water as quickly as possible will be the cheapest setting.

Having a low setting will keep the boiler cycling on a off until
the rooms reach temperature.

When you next have the boiler serviced ask the service engineer
to set the boiler to it's minimum burner output therefore the boiler
will also be running for longest getting to the required temperature
and keep cycling to a minimum.

If you haven't got a hot water tank thermostat get one as this
will cut the boiler off when the water is hot.
Only heat the hot water first thing in the morning and early evening
for an hour or so. Keeping hot water hot wastes gas.

 

[HERTS P&D]

Your room stat should be in the living area of your home and adjusted from there.

Andy

 

[45yearsagasman]

it will cause backend condensation.

Ooooh matron

 

[toonburner]

Thanks for the replies. Mine is a fully pumped system that has been regularly serviced ( although I have had to cancel the service contract due to finances) and I do have a thermostat on the hot water tank,set at 60 degrees. I've been reading some other posts on here and saw one about a radiator without a TRV on it. All our radiators have TRV's except one which is in the hall,which is where the stat is (this was where the house builder put it!) Should I turn this rad down, and if so, which valve do I turn, left side or right?
On another note, if I replace this boiler (considering it;s age) with something more efficient, can anyone guesstimate how long before I see a return on the investment? And finally, could anyone recommend a high efficiency boiler to power 13 rads?

 

[ALEC1]

for return on investment i would look else where... many things have no ROI and actually loose value the minute you buy them, cars for example..


a new boiler is an investment in comfort..with the possibility of reducing running costs...

 

[toonburner]

sorry, I may have worded that wrong, what I really meant to ask was is it worth getting a new boiler considering the high initial cost and subsequent small saving in gas costs?

 

[ALEC1]

it depends on your values, I would argue yes but thats how I make a living...

if the boiler and system are issue free then wait until something happens, then when it does treat your self to one repair and change it..

a decent installer will also ensure the system is in good condition... to ensure that the boiler can operate

it may be an idea to upgrade valves etc at the time of changing the boiler...

 

[JohnD]

turn down the room stat, then the boiler won't run at all when the house is as warm as you have set it.

 

[gaswizzard]

turn it down too low and it will cause backend condensation.

I think the boiler manufacture has this in hand with respect to the MINIMUM temperature this boiler can be set too (55c) , if we were to consider the low CO2% in flue gas (max 5% for this boiler) then it will be seen that flue gas due point temp will be around 45/50c , not a problem.

 

[dcawkwell]

sorry, I may have worded that wrong, what I really meant to ask was is it worth getting a new boiler considering the high initial cost and subsequent small saving in gas costs?

Unless the existing boiler breaks down and the cost of repair is fairly high.
There is no financial case to replace the boiler. The savings
on fuel will not be enough.

 

[rich4nancy]

You could look at this in a different way. If it cost say 2k to replace your boiler etc you could potentially at 20% savings on gas save around £240 from your £1200 annual bill. If you leave the 2k in a cash Isa for a year best return on Market at the minute will pay you about 70 quid?

Where best to put your money??

Regards

 

[JohnD]

except that (on your figures) at the end of year 1 he would have £240 in the bank if he bought a new boiler, and £2,070 if he saved the money.

 

[dcawkwell]

You could look at this in a different way. If it cost say 2k to replace your boiler etc you could potentially at 20% savings on gas save around £240 from your £1200 annual bill. If you leave the 2k in a cash Isa for a year best return on Market at the minute will pay you about 70 quid?

Where best to put your money??

Regards

On a plane ticket out of this country to somewhere warm and sunny.