How long does it take to heat your house?

[doctor Bob]

Ground source heat pump here ............... just keeps house at 24 all the time, lovely. Still waiting for first bill but hopefully cheapish, 1kw in 4kws out... plus I get a grant for the next 7 years.

 

[Some bloak]

This, after all, is how an aga works ...its not designed to be allowed to go coldevery night ...its always on. I figure that AGA have probably thought about why they recommend its used that way on oil fired ones. But who knows!

We treat our stone cottage like an Aga. One or both of our log burners are banked up every night. It works a treat.

+1 for keeping the fabric of the house warm all the time- especially a stone house. Ours will consume the best part of 10 tons of seasoned wood per year in doing so. If you do let them cool down, such as if you're away, then it's a penguin job. Nice to enjoy the coolness of a stone house on a hot summer's day though.

 

[paulrockliffe]

You're talking about something different though, if your house gets cold you don't have the heating capacity to heat it backup again. Burning 10 tonnes of wood means your house is leaking a lot of heat, whereas the other chap is claiming his house is so efficient that keeping the heating on all the time is cheaper.

The Aga is designed to run all the time because it has a fairly basic burner that is inefficient outside a narrow output range and likely to coke itself up given half a chance. But primarily because it takes ages to heat up enough to cook your dinner that it isn't practical to turn it off. Especially if it does hot water too. Again, this is not the same thing as keeping your heating on all the time because it's cheaper! Agas are notoriously expensive to run, because they're not overly efficient, but also because they're on all the time.

If the anecdote about keeping the heating on all the time is true, then the laws of physics are being broken. Heat loss over a temperature gradient is directly proportional to the difference in temperature, so if the structure is kept hotter, more heat will be lost and, conversely, if the house is kept cooler less heat will be lost. So without any other factors being added to the mix, running the house cooler at night must leak less heat than keeping it warm, which must mean less heat input required and less cost.

For the anecdote to be true what is likely to be happening is that when heating the house back up there was over-heating taking place, compared with the setup that's got the heating on all the time. In that case the cost could be higher, but running it all the time must be more expensive than letting it cool at night, but not over-compensating when reheating.

 

[Sheffield Tony]

0
14
22
Never
4 bed Victorian solid stone detached

The 22 and never imply there is at least 1 female in this house

Has anybody tried to explain that, if the thermostat is calling for heat, turning up the dial wont increase the rate of heating only the final temperature........

Yes, many times :roll: Explaining that a bit of physical activity might help is even more dangerous ground.

 

[Keithie]

sorry ...but I cant help myself ... we're not really talking about energy so much as money and energy when it comes to cost efficiency of heating a house overnight. There could be any number of other explanationz....one of which might be economy 7 heating (ie lower elec tariff overnight), but who knows!

Personally I do favour the laws of thermodynamics being wrong

We all know that there's been a government conspiracy for decades, in cahoots with energy companies, to cover up the existence ofperpetual motion machines

Looks now though likethe cat is out of the bag (and both dead & alive probably) with the successful peer review of the EM Drive rocket engine (fuelless). Obviously we can rely on high credibility sources like Forbes magazine to giveprecise insight into cuttingedge physics ...so it must be true ..

http://www.forbes.com/sites/startswitha ... f31cc1692c

 

[RobinBHM]

My understanding is that many modern houses have the insulation positioned in the inside, IE in the cavity, thermalite internal walls, loft insulation at ceiling level etc. The result is that such houses can be extremely well insulated with very little heat loss, however they also have very little in the way of dense material on the warm side that can act as a thermal store. That means if you turn the heat off, the house whilst well insulated will cool down fairly quickly. I believe there is now a school of thought that considers there should be an increased amount of material that can act as a thermal store. I believe one type of house is better for people out working during the day and one type is better for people at home most of the day. Dont ask me which, Im confused!

 

[transatlantic]

Has anyone put in cavity wall insulation? how much of an improvement did it make?

The outwards facing walls in my house are always stone cold, which I assume is where I am losing the heat, so I'm hopeful it could give some real benefits. I just worry about the cases I have read where it has actually made things worse in causing severe damp. I'm also going to add more insulation in my loft as its less than the suggested 270mm.

 

[Phil Pascoe]

The R.I.C.S. apparently advise not to have it fitted where there is wind driven rain - so that counts out much of the UK so far as I can see.

 

[Jonzjob]

My understanding is that many modern houses have the insulation positioned in the inside, IE in the cavity, thermalite internal walls, loft insulation at ceiling level etc. The result is that such houses can be extremely well insulated with very little heat loss, however they also have very little in the way of dense material on the warm side that can act as a thermal store. That means if you turn the heat off, the house whilst well insulated will cool down fairly quickly. I believe there is now a school of thought that considers there should be an increased amount of material that can act as a thermal store. I believe one type of house is better for people out working during the day and one type is better for people at home most of the day. Dont ask me which, Im confused!

Our thermal store is 190 sq m of terra catta tiles sat on top of LPG fired wet underfloor heating. We keep the temp at about 20ºC all the time. What's the point of letting it cool overnight to have to be boosted during the day? From switch on, normally mid/late December, it takes about 12 hours to warm up and from then on it's comfortable. We have an open wood fire for a 'cozy' factor.

OK, we live in the south of France. At the moment the outside temp is 1ºC with a wind chill of -5 and it gets a lot cloder than that. We are not high up, 150m. We have 2 prevailing winds, NW and SE. The NW is called the Tranontane and in the winter it's also called the Mini Mistral! That blows more than the SE, the Marin, which is a damp wind that drops the temp just as much. In general it is colder here through the winter than it ever was when we lived just outside Stroud, Glos.

If you have never had underfloor heating then you just don't know wha you are missing. No wall space lost with radiators, no hot spots and a nice warm, cozy feeling all through the house and the ability to walk around barefooted all year round..

On a sunny day the heating is also helped by 27 sq m of direct south facing windows and on a cold sunny day our bedroon will get to 27ºC in the afternoon 8)

 

[Beau]

Ground source heat pump here ............... just keeps house at 24 all the time, lovely. Still waiting for first bill but hopefully cheapish, 1kw in 4kws out... plus I get a grant for the next 7 years.

Same here Bob but run a lot cooler. We leave it to tick away keeping the house at 17c and use the wood burner in the evenings which quickly brings half the house to 24c then I fall asleep haha.

Ours has proved cheap to run but the higher temp you run it the lower the COP.

 

[DennisCA]

That's what we got in our house as well, we have an accumulating masonry heater (finnish contra-flow design) for additional heat so we can run the pump lower. I'm controlling the heat pump using the outdoor temperature only and a heating curve.

 

[Beau]

I'm controlling the heat pump using the outdoor temperature only and a heating curve.

Yes I was told that was the most efficient way. Surprising how stable it is once you get the heat curve set. Love the idea of a masonry stove but not sure necessary living in the SW of England as opposed to Finland . Would be a fun project though

 

[Phil Pascoe]

Our local hospital's heating is controlled by the outdoor temperature ... of the hospital ten miles away on the other cast, where the weather is different. :? Over ten to fifteen miles the temp. can vary 8c sometimes.

 

[paulrockliffe]

Underfloor heating and other thermal stores are great and can be very efficient even with extra heat loss over night, not exceptional but they're good at taking 'lifestyle' factors that often increase costs out of the equation because they're too slow to react. But for most people where the house is empty most of the day as well they're not a great solution cost-wise because heat loss is constant whether you're in or not.

I'm lucky to be on mains gas, combi boiler with a lot more radiator capacity than recommended. Coupled with a very accurate thermostat the heating is similar to underfloor in that it's always just nice, you can't tell whether it's on or off, the house just feels right. But it heats up very quickly as well so it's a great solution for us as we're out of the house most of the time.

 

[skipdiver]

I just heat my workshop and go in there. If i actually do some work as well, i soon get too hot and turn off my small blow heater.

 

[Bodgers]

4 bed semi built in 2010. Takes about 20-30 mins or less to get it up to 19-20 from most winter temps (0-6c).




Sent from my iPad using Tapatalk

 

[Bodgers]

My understanding is that many modern houses have the insulation positioned in the inside, IE in the cavity, thermalite internal walls, loft insulation at ceiling level etc. The result is that such houses can be extremely well insulated with very little heat loss, however they also have very little in the way of dense material on the warm side that can act as a thermal store. That means if you turn the heat off, the house whilst well insulated will cool down fairly quickly. I believe there is now a school of thought that considers there should be an increased amount of material that can act as a thermal store. I believe one type of house is better for people out working during the day and one type is better for people at home most of the day. Dont ask me which, Im confused!

My house was built in 2010 and that is close to what I observe. Ours does have a concrete slab base though, and you would have thought that would have a storage effect. Probably limited due to the thermal underlay and oak flooring I have put on top of that though

 

[John Brown]

4 bed semi built in 2010. Takes about 20-30 mins or less to get it up to 19-20 from most winter temps (0-6c).




Sent from my iPad using Tapatalk

INVU
We came back from two week in sunny Hawaii on the 6th January to a boiler problem, and our house was at 3c. It took about 15 hours to get it warm.
Detached 4 bed built in 1894, no cavity wall insulation, no double glazing.

 

[transatlantic]

4 bed semi built in 2010. Takes about 20-30 mins or less to get it up to 19-20 from most winter temps (0-6c).




Sent from my iPad using Tapatalk

What is the indoor starting temp though? I assume if it's a modern build the indoor temp won't drop much below 16c, even in winter?

 

[Bodgers]

4 bed semi built in 2010. Takes about 20-30 mins or less to get it up to 19-20 from most winter temps (0-6c).




Sent from my iPad using Tapatalk

What is the indoor starting temp though? I assume if it's a modern build the indoor temp won't drop much below 16c, even in winter?

Ive not taken readings. This would be about right after leaving the house for a working day with no heating on during that time.

I would image it would be somewhere between 12-15C. Not sure.

2 years ago I accidentally left the back door wide open for a full day in December. It was basically outside temp inside. Took about 2 hours to get to temp.





Sent from my MI 3W using Tapatalk