The Poultry Keeper

Clucky · Joined: 22 Jul 2006 Posts: 2126 Location: Shropshire

We have just had the lagging and wall insulation done in our house and we have noticed a change but wonder....

As we work during the day leaving latest 8.00am and returning at 5.30pm should we leave the heating on tick over at a low temp to keep the walls warm, or turn it off which we have been doing? We currently have it come on at 6.00am, off at 8.00am, on at 3.40pm and off at 10.30pm

We now notice that come 11.00pm after the heating is off, the house is lovely and warm for a very long time afterwards.

Does anyone use the "on all the time" method?

We do try and cut down on waste, recycle etc so what do you think is the logical method. Burn up loads trying to warm a house before we get home, or keep it ticking over?

CP · Posted: Sat Jan 05, 2008 3:14 am Post subject:

Ours gets turned off when we're out but is set to come on if the temperature gets too low. So I suppose it's a bit of both! Confused

Pat · Joined: 02 Jun 2005 Posts: 561

Mine stays on all the time at 17°

stephen · Posted: Sat Jan 05, 2008 7:20 am Post subject:

The Scandinavians are very big into energy saving, and part of the job I do is training people to install, run and maintain control systems for heating systems and help them save energy. We've also spent the last 18 months or so getting our heating strategy right.

In theory turning off the heating when you are not in saves energy.

In theory.

If you have a perfectly insulated house that doesn't lose much heat. And you're not human. And know when you are coming back and can program it perfectly.

In theory.

In practice, however, turning the heating down when you are out will often save more energy. Also turn off or turn down the heating between half-an-hour and an hour before your usual bed time. You won't notice the house cooling substantially in that time! Nigel hasn't....

Knocking the heating down 1° when you are out will cut heating costs by around 10%. It's pretty cumalative, to a point. On a normal day, you'd expect the house temperature to drop maybe 2-4°C. On a cold winters day, it could be a lot more. Setting your thermostat around 4°C lower during the daytime wouldn't be a bad thing!

If the house gets too cold when you are out, and the heating is off completely, the heating system needs to use a very large amount of heat to get the house back up to temperature when you get back in. The lag time and amount effort needed to get it back up is a lot. That costs money. Remember, the heating system not only has to heat the water in the pipes, but the pipes themselves, the radiator panels, etc etc. It isn't 100% efficient.

It can take a long time for the house temperature to get back up to normal again if it goes too low, and you tend to get overshoots in temperature - partly because the natural thing to do is bump the thermostat up a few notches when you come in and put on the fire for a while, and secondly because the controls on radiators and central heating systems are pretty pants!

As a result of humans being humans, and home heating systems being pretty poorly controlled, you waste a huge amount of energy - a lot more than you saved turning off the heating.

The image below shows heating controlled by humans and a traditional heating system on the left of the green line, and on the right is a computer controlled heating system. The boiler is the same, the radiators are the same. The only differences are to do with changing temperatures for occupancy and unoccupancy, and the radiator controls.

You can see on the left there is a lot of variation in temperature inside the house (red line)! On the right the heating stays pretty constant all day, and drops back a few degrees at night.

The controls on the left cost around 30-55 units of electicity every day.

The controls on the right 13-25 units per day.

You can read a bit about all that we've done here

A final point, Scandinavians use heat pumps a lot for home heating (we have one, too). The companies that install them recommend leaving them switched on day and night for best energy savings, and to just adjust the radiators/thermostats a little when you are out.

Tony Sirett · Posted: Sat Jan 05, 2008 11:02 am Post subject:

we leave ours on all the time, set at 20C, the rule is if your cold stick another jumper on Wink

Henwife · Joined: 31 Jan 2006 Posts: 2624 Location: Monmouthshire

No gas here anyway. Our system is controlled by the outside temperature to keep the house at about 60F throughout the day, slightly lower at night. The outside walls are 2' thick solid stone, but the windows are single glazed. there are open fires in the two most used rooms, and these are lit if we're cold (or if we can't be bother, just add another jumper), and there's the Aga in the kitchen.
Periodic visits by energy savings bods give us endless enjoyment - they've no experience of a system like ours and usually leave, scratching their heads in bewilderment! (Being a listed building, there are limits to what can be done to the house anyway).

bronskibeat · Joined: 09 Sep 2007 Posts: 1385 Location: Clawddnewydd

Henwife, snap!! Thats the type of system I'll have in a couple of weeks when I finally move. Walls enormously thick, open fires/stoves in the living rooms, rayburn in the kitchen. House is listed (just Rolling Eyes

) so does this mean I'll have visits from energy efficiency bods too??

At home at the mo, we have oil which is set to come on twice a day but if it gets very cold, we have it on constant. My theory has always been based on strip lights, they cost more to turn on and off than to keep on for periods of time. I have always wondered if heating runs roughly to the same theory.

Gilly C · Joined: 22 Jun 2006 Posts: 2170 Location: South Cumbria

during the week when it is only me except for 2 nights we move into the computer room leaving the large room unheated there is a telly in there and on Fridays we use the large living room for the weekend unless we go away to Yorkshire it seems so wasteful heating a large room for 1 person we have always worked this way suits us

Sparklepeeps · Joined: 17 Jan 2007 Posts: 1875 Location: Cheshire

On all the time, but use the thermostat to control level of heat.

....only because we dont know HOW to turn the damn thing off! (and we have lived here 18 months now! Confused

)

NannyP · Posted: Sat Jan 05, 2008 2:14 pm Post subject:

We've been having a right old time with ours this winter. It is oil fired and we had been leaving it on low constantly, but used 600 litres of oil in 6 weeks and cannot afford to do that!

So, after taking varying pieces of advice on another forum, we insulated the boiler room itself, and the empty attic space above it. All send and return pipes were insulated and Mark added a timer. So, we have had to change how we operate as we cannot afford to keep filling the tank with more and more expensive oil. Currently the heating comes on from 8 til 12, and then again 4 til 10. It is pretty mild here currently, so we turned it off last night, as after 5 we light the open fire in this large room and close the doors. We are in the process of buying a woodburner, as the open fire is incredibly inefficient (they all are). So, our plan is to install woodburner, and burn less wood but get loads more heat. Next winter we hope to have enough to add a back boiler and run the heating and hot water from the woodburner. We hope the woodburner will warm much of the house anyway, although it is a very big house. Next to this room (but curtained off) is a massive entrance hall which goes right up high into the eaves. It is lovely and of course a great place for all the heat to rise to.

stephen · Posted: Sat Jan 05, 2008 2:18 pm Post subject:

Are pellet burners and wood pellets available where you are? They are getting increasingly popular here, and are even more efficient than wood burners. You can even get electrically fed room pellet burners here for around the £1000 ball park.

NannyP · Posted: Sat Jan 05, 2008 2:21 pm Post subject:

Yes, we can get pellet burners, but we have so much of our own wood, not sure we would be saving.
We have a double garage with loads of wood stacked in and seasoning, some of which will be ready next winter.

CP · Posted: Sat Jan 05, 2008 2:33 pm Post subject:

We have 2 multifuel burners, one of which is connected to the heating/water system so when we're at home (evenings & all day weekends) the oil gets turned off & the house is heated by the fire.

We also have thermostats on each individual radiator. Wink

Fenn · Joined: 16 Jun 2005 Posts: 2292 Location: Shrewsbury

Our gas heating is on permanently, at 15deg C. We turn it down to 13deg C at night.
We have radiators in all rooms but rarely need them on on the top floor as the heat rises from the other rooms.

Have you got a main stat, Clucky? I'd just leave it on low whilst you're out and turn it up a bit when you get home. THat way it will click in if the house gets really cold, but won't waste energy overheating it when it's not needed.

Clucky · Joined: 22 Jul 2006 Posts: 2126 Location: Shropshire

Wow, Stephen that is fascinating and really helpful, thank you.

I think we are converted and will keep it on all the time

Fenn we do have a thermostat in the livingroom next to the didges and we do fiddle a little.

Tony, I love to snuggle under a fleece cover at night in the livingroom or throw an extra jumper on. If OH would allow, I would use the dog as a hot water bottle. We run our house at 20 degrees in winter, and occasionally indulge at 21 degrees, but then feel guilty Rolling Eyes

We do have a gas fire too, but never use it.

I want to buy a condensing boiler but money dictates Sad

so our "F" efficient boiler will have to do for the time being.

Henwife/NannyP we use to live in a semi detached house with thick walls, single glazed windows, oil central heating, electric cooker (shame really when the kitchen was 20ft square it could have done with an aga) and a coal fire in the living room. The house was huge, living, kitchen bedrooms each were approx 20ft square and the house was b****Y freezing. I remember OH standing at the cooker in winter with two fleeces on and ice on the inside of the windows.

And boy was the oil was expensive!!!