Energy myth-busting: Is it cheaper to have heating on all day?

Swipe

My bedroom is 11C when i go to bed and 8C when I wake. I'm never cold in bed. Warm bedrooms are so overrated

John_Pierpoint

I actually enjoy knowing what season it is, it makes one feel more alive and attuned to the climate.

However you pays your money and takes your choice:

Beware of respiratory problems, otherwise known as bronchitis and feeling cold makes the blood thicker and thus a stroke or more heart attack more likely.

http://www.globaltimes.cn/content/826084.shtml#.Uo7YySdfp20

http://eurpub.oxfordjournals.org/content/18/4/399.long
Key points

• About 50% of homes of elderly patients with a chronic obstructive lung disease had LR temperatures of <21°C at 5 pm.
• Better health status was associated with more hours of indoor warmth at and above 21°C.
• Patients who were current smokers showed more benefit of indoor warmth on health status than non-smokers.
• Results support a policy of funding domestic energy efficiency improvements to achieve affordable warmth and health benefits.

Personally I think the health effects of a cold bedroom are also related to the "overcrowding" of the building, ventilation (room ventilated to dry every day, condensation removed and black mould treated) humidity and of course the health/age of the occupant.

Given an electric blanket to heat the occupant and the immediate area and air breathed, a cold bedroom should not automatically mean ill health.

DragonQ

Swipe wrote: »

My bedroom is 11C when i go to bed and 8C when I wake. I'm never cold in bed. Warm bedrooms are so overrated

Mine tends to be 16-17 when going to bed and 14-15 when waking up. Having it too cold just makes it harder to get up from under the covers!

Leodogger

We have a thermostat in our hall in the bungalow we have just moved to and it cuts out once it gets to 19c (we have the timer set for 3 hrs in the morning and 4-5 hrs in the evening) but the strange thing is that though we have radiator thermostatic valves on all the radiators turned to max, our kitchen and the bedrooms are always freezing even when the heating is on. I have noticed that the radiators are only approx. 24" wide (doubles) in the bedrooms and the rooms are approx. 12ft x 9ft and I do not think they have a big enough output. Also in the hall which is quite wide the same size but single panel which is also quite cold. The front door is hardwood with side glazed panel which we are thinking of changing to UPVC or similar to help keep the heat in and we have 2 windows and a half glazed hardwood door (double glazed but not the max. space between panes as in UPVC), though the kitchen is only 9ft by 9ft it is quite cold even when the heating is on, again the radiator is only 24" double. The only relatively warm room is the living room which has a double panel radiator (convector type, apprx. 6ft) plus we have the fire on all the time. We have double glazed UPVC windows in the bedrooms but this does not seem to help much in keeping the rooms warm

Could our extreme difference in temps between rooms be down to the size of the radiators, the hardwood window frames on the side and back where the bungalow faces north, or a combination of all three ?

John_Pierpoint

Are we talking terrace, semi, detached?
How old is the property and how old is the central heating system ?
Can we assume it is gas fired?
Can we assume it is double glazed? If so how wide is the gap.
What is the flow (boiler) temperature set at?

Much more to the point have you eliminated all drafts and got the 10 inch insulation in the loft and the wall cavities filled.
If the floor is "suspended", you might be able to get underneath and insulate the floor too.

As far as the heating goes and assuming you have it on a two pipe system, you need to balance the radiators so that they all come on at top heat before setting the thermostatic valves.

The hall thermostat is largely redundant if all radiators have thermostatic valves and it needs to be set high enough to be the last thermostat to turn off, not the first one.

Cardew

Agree with the above about the CH system probably needing to be balanced.

Another possibility is the water temperature on the boiler(for the radiators) is not high enough.

You can check if the radiators for the bedroom and kitchen are of adequate size by shutting off all other radiators and checking one room at a time.

The kitchen and bedroom radiators should be as hot to the touch as the lounge.

orrery

Cardew wrote: »

Agree with the above about the CH system probably needing to be balanced...Another possibility is the water temperature on the boiler(for the radiators) is not high enough.

Having had a new boiler fitted, I'm going though exactly this process myself.

Firstly, getting the boiler temperature up by 5 degrees makes a significant difference to the heat transfer.

You could turn the hall thermostat up - try 21C for a start.

If the flow is inadequate, look to see if the flow can be turned up at the pump.

Balancing the system: Firstly, I'll assume that there is no thermostatic valve on the hall rad - if there is, open it up to full. Using a standard isolation valve (the one usually found at the other end to the thermostatic valve) turn the hall rad to off, then open the valve by about quarter of a turn. Initially, from a cold turn on, you'd want the hall rad to just get warm at the top. As the rooms come up to temperature and their thermostatic valves close down, more water will be forced to the hall rad, which should then come fully up to temperature, heat the hall and then shut down the heating by tripping the hall stat. Adjust the valve from 1/4 turn to get the required effect.

Warning: this may reduce the flow through the boiler and cause it to 'kettle' or otherwise misbehave when the system is up to temperature. At that point you'd need to talk to a plumber who understands heating.

Leodogger

John_Pierpoint wrote: »

Are we talking terrace, semi, detached?
How old is the property and how old is the central heating system ?
Can we assume it is gas fired?
Can we assume it is double glazed? If so how wide is the gap.
What is the flow (boiler) temperature set at?

Much more to the point have you eliminated all drafts and got the 10 inch insulation in the loft and the wall cavities filled.
If the floor is "suspended", you might be able to get underneath and insulate the floor too.

As far as the heating goes and assuming you have it on a two pipe system, you need to balance the radiators so that they all come on at top heat before setting the thermostatic valves.

The hall thermostat is largely redundant if all radiators have thermostatic valves and it needs to be set high enough to be the last thermostat to turn off, not the first one.

In answer to your questions:

Our property is semi detached, 1960's, cavity wall insulated and as stated side and rear windows are double glazed but hardwood and minimum 8mm gap.

Loft has maximum insulation, floors are solid concrete as all gas central heating pipes are run up the walls and through the loft back down to the boiler.
As for the boiler thermostat temp., don't know where that is sited, read out on the front says 46c but nothing else is visible except a two dials for radiator and water with graduated marks for low and high.

As for eliminating draughts, we intend to do that by replacing our hardwood door and side panel for a more energy efficient door and panel, composite door and upvc side panel and frame.

Leodogger

Cardew wrote: »

Agree with the above about the CH system probably needing to be balanced.

Another possibility is the water temperature on the boiler(for the radiators) is not high enough.

You can check if the radiators for the bedroom and kitchen are of adequate size by shutting off all other radiators and checking one room at a time.

The kitchen and bedroom radiators should be as hot to the touch as the lounge.

All radiators are as hot as each other but after several hours the bedrooms and kitchen are not nearly as warm as the lounge but as we have a gas fire in the lounge as well as a radiator which I have to admit I don't have on full as I prefer the gas fire on, they are not likely to be although the gas fire is on the low position and the radiator is on 3. All I can say is, if I decide to spend time in the bedroom whilst the heating is on, I have to put on a halogen heater and snuggle up under the duvet to watch the telly, otherwise it is too cold to sit in there.;)

Leodogger

orrery wrote: »

Having had a new boiler fitted, I'm going though exactly this process myself.

Firstly, getting the boiler temperature up by 5 degrees makes a significant difference to the heat transfer.

You could turn the hall thermostat up - try 21C for a start.

If the flow is inadequate, look to see if the flow can be turned up at the pump.

Balancing the system: Firstly, I'll assume that there is no thermostatic valve on the hall rad - if there is, open it up to full. Using a standard isolation valve (the one usually found at the other end to the thermostatic valve) turn the hall rad to off, then open the valve by about quarter of a turn. Initially, from a cold turn on, you'd want the hall rad to just get warm at the top. As the rooms come up to temperature and their thermostatic valves close down, more water will be forced to the hall rad, which should then come fully up to temperature, heat the hall and then shut down the heating by tripping the hall stat. Adjust the valve from 1/4 turn to get the required effect.

Warning: this may reduce the flow through the boiler and cause it to 'kettle' or otherwise misbehave when the system is up to temperature. At that point you'd need to talk to a plumber who understands heating.

I don't quite understand these instructions as I don't understand heating, sorry, but I think I need a plumber anyway as if the boiler does "kettle" I am back to square one and will need a plumber at that point.