Wasting money heating one room?

L_a_y_l_a

Very concerned about my elderly parents. They have a move moveable thermostat, which is usually in the one room they want to heat, and so heating switches off when it gets to that temperature.  However, often they watch TV in separate rooms (football/SCD), and to compensate they run a fan heater in the other.
They have the other radiators turned off. Their house is freezing and they have big bills.

My question is, are they not wasting money by turning off other radiators? The water is being pumped around the house all the time the moveable thermostat determines, so why not get the benefit in all these radiators by turning them on? Then there is more heat in the house.

Is it more expensive to have the heated water go up through the radiators when circulating anyway? That's what my dad thinks, and uses that as his reasoning to just heat that one room, plus fan heater in the other.

It doesn't make sense to me. I should point out I have not had big bills and not been cold, it's not my management I am questioning.

But if the general advice is now going out, say on BBC, heat one room, could that not start having people not getting the benefit of what they're paying for as the water circulates anyway, just bypassing radiators instead of going through?

I have tried to describe this scenario as best as I can.

I just don't understand it.

[Deleted User]

Your boiler puts energy in the water.

Radiators take energy out of the water and put it in the rooms.

If you have more radiators on, more energy comes out of the water so your boiler works harder to put it back.

Whether that's more or less extra than the fan heater is the important question. I would guess less.

victor2

Welcome to the forum!
When radiators are turned off, the hot water being pumped round effectively bypasses those radiators, but does of course go round the pipework for delivering water to, and returning it from, all radiators. So there is a relatively small amount of energy used in providing that, although you could argue it provides a little heat into the house itself.
If the radiators have Thermostatic Radiator Valves (TRVs) on them, then they will automatically shut off when the set temperature is reached, unless the main thermostat has already decided to shut off the central heating.
Using a fan heater in another room probably is more expensive than just turning that radiator on, especially if it has a TRV on it.
New central heating installations include TRVs. If your parent's system doesn't have them, they can be fitted at not too great a cost. Worth getting quotes from a heating engineer to do so if that is the case.

Astria

I find it cheaper to use an oil filled radiator in my office at home than the central heating as otherwise so much gets heated that doesn't need heating, and if I turn all the radiators off the boiler will constantly short-cycle because not enough energy is being taken out of the water and so it goes over-temperature.

The best thing can do is check for themselves, how much does the fan heater cost for a typical day? the next day, turn off the fan heater and use the central heating, how much did that cost? Gas is a 3rd of the cost of electric so it could end up cheaper to use the radiator than a fan heater, but if they are warming the person and not the room, then the heater could be cheaper....

doodling

Hi,

The more radiators your boiler has to heat, the harder it will work and the more gas it will use.  The water doesn't cool down much in the pipes but does cool down quite a lot as it passes through the radiators.  The boiler needs to burn gas to make up the heat lost.

It will be cheaper to use the central heating to heat the second room because gas heating is around a third of the price of electric heating.  It will mean that more gas is used, but as gas is a third of the price then your parents will still be better off than if they'd used the electric heater.

dunstonh

Their house is freezing and they have big bills.

Perhaps we need some context on what you describe as "big".     Their use as you have described it would expected to be low.    However, some have different views on what is big.

Heating the rooms you use and turning off (or down) in rooms you don't use is usually the best way.    Modern TRVs can have timers on them making it easier to control movements around the house.   However, they are relatively expensive and need use of an app which may make them difficult for an elderly person.

L_a_y_l_a

Thank you, I understand that some people can have valves fitted on individual radiators too, the TRVs, and that electricity is more expensive than gas.

So the water cools a lot in the radiators, and as the water temp drops in the system, this calls the boiler to come on and heat it back up?  I think someone commented that that is the design of the system. Yes, I can understand that, but it just seems that it should perhaps be allowed to run that way?

You see what you are all saying makes sense. I also understand heating the person, but my mum has arthritis,  and the fan heater is on an awful lot.

We had a distant family member die of hypothermia,  above my parents generation. She was a but eccentric, but I know that worries my mum.

I cannot get my dad to try another way, as he's so convinced it would cost him more. I think it would be less.

I haven't worked his way, in different kinds of properties and systems,  and I always had low bills, despite heating whole place. I would do my best to heat myself with throws, extra layers, etc, but their house is so bitterly cold and damp all over, my mum doesn't heat properly,  and I have never been as cold as when in their house.

I cannot operate my system as usual at the moment because I gave a very cold room because builders haven't come leaving me with a freezing kitchen/living space next to my bedroom. My bedroom is colder.

I know you cannot answer specifically about their home, as there can be different factors, but I really am questioning if their approach can be right, paying all that to freeze a lot of the time, staying in one room not heating up when changing rooms.

Thank you for your kindness in trying to talk me through this, as I have tried talking with them many times about it.

victor2

Maybe buy your mum a heated throw for Christmas? They are not expense to run, much cheaper than a fan heater, and can be beneficial if she's just sitting one place watching TV or similar.

BUFF

If their boiler is running anyway to provide heat to 1 room & there is a 2nd occupied room I would also heat that room via the boiler. 
Running just 1 radiator from a boiler can actually cause issues for the boiler as Astria mentioned earlier.

L_a_y_l_a

Thanks, the bills are a few hundred pounds per month. Not a lot to some, but a lot to others, but despite paying that, their house is freezing, and they are running the system. I don't think it's to do with insulation.

The heated throw is a good idea, I hadn't explored that, because an electric blanket malfunctioned under me as a child, fortunately I wasn't burned and she caught it when still at singe stage, but my mum likes hers still.
They wouldn't handle apps.

Probably the only way to know is for them to try it out another way.

Do people notice the difference in their bills positively by heating the one room? Likewise,  I guess all houses are different,  so people need to try these different suggestions as they're reasonable. 

amcc1

It sounds like the fabric of the building isn’t getting a chance to warm up properly. If the house is fairly well insulated (how old?) and not too large - say 3 bedrooms or less, then personally, I think there is an argument for heating the whole house, especially during the 3 coldest months.

If your parents pay their council tax over 10 months (getting a payment holiday in Feb/Mar), then they could allocate that money to the heating for those 2 cold months.

It might take extra energy for a few days while the place warms up but then should take less to keep it warm. Even if it costs an extra £1 a day for three months, the comfort might be worth it, especially for older folk who might not be able to get active to be warm. It’s surprising how turning the heating on and off (in a kind of boost mode) can work out as expensive (or more so?!) than keeping it on at a lower temperature for more of the time.

Apparently, for ventilation, it’s a good idea to open windows for 5 mins a couple of times a day to change the air, rather than having a constant trickle of cold air. Again this avoids the building fabric losing warmth.