Turning off spare radiators = Cheaper Gas Bills???

stokefan

Biggles wrote: »

Four weeks isn't long for a useful test and you would need the weather to be identical for the 'test' to be any use. But, even so, there was a difference, then?


I think you mean 'the boiler will be constantly running' (rather than 'boiling', as Cardew pointed out) but apart from that you are right.

yes thats what i meant sorry

Cardew

confuseddad wrote: »

If you have radiators fitted with trvs. Should the other valve be fully open. Not sure my trvs are working, Can you check.

Turned it up on 1 rad from 2.5 rad was cool, to 3.0 rad was piping. Also by turning rads off are you inhibiting the system flow?

Is it not beter to have them on very low, so water is flowing? Pardon my ignorance but is central heating flow and return only as water is pumped around the whole system at the same time. If there is a rad of then is there is a blockage as no water is flowing????

The TRV makes no difference at all to how hot the radiator gets.

Water is circulating around the CH system at the temperature you set on the boiler(typically 70C to 80C). As soon as the TRV senses the room air temperature is below its setting it opens and the 70/80C water flows into the radiator. So the radiator gets just as hot if the TRV is set to '1' or '5'. The only difference is on the lower settings the TRV shuts off quicker.

The CH radiators being shut off will make no difference to the flow of CH hot water around the system.* They are not connected 'in series' i.e. the water doesn't have to flow through the first radiator in the system(it can be shut off) to reach the second radiators etc.etc.

* In case anyone comments.

Some CH systems require one radiator to not have a TRV fitted(normally in the room with the wall thermostat) as when all radiators are off the water will not circulate and the pump could still be running.

Other CH systems have TRVs on every radiator as they have an automatic bypass valve that allows circulation of water even with all radiators off.

Cardew

surely it just depends where your thermostat is in your house, if its in acold part of the house and you switch the radiators off in that room the boiler will be consistantly boiling??

I think you mean 'the boiler will be constantly running' (rather than 'boiling', as Cardew pointed out) but apart from that you are right.

stokefan wrote: »

yes thats what i meant sorry

Depends what you mean by 'the boiler will be constantly running'

The boiler will 'fire' until the hot water in the system is at the temperature you have set on the boiler - say 75C. It will then switch off and so will not be 'running'.

When that water temperature drops to, say, 70C it will fire up again until the water temperature reaches 75C and then switch off again.

I think what you mean to say is if the wall thermostat is in the cold part of the house and you switch of the radiators in that room then the pump will be constantly running. That of course is true, but the boiler will still switch on and off, as stated above, as the water reaches the set temperature.

greenbee

Cardew wrote: »

The CH radiators being shut off will make no difference to the flow of CH hot water around the system.* They are not connected 'in series' i.e. the water doesn't have to flow through the first radiator in the system(it can be shut off) to reach the second radiators etc.etc.

* In case anyone comments.

Hate to be the one to comment ... let's just say 'in the majority of cases' . My parents house has a number of rooms where the upstairs radiator is dependent on the downstairs one (as they used open fires for heating the sitting, and didn't need the radiator on there, I spent a lot of my childhood freezing as my bedroom radiator was cold!). This may be typical 1940s plumbing... or just the peculiarities of their house.

Given the amount of overly ambitious DIY done these days, you never quite know what you're going to end up with...

Cardew

greenbee wrote: »

Hate to be the one to comment ... let's just say 'in the majority of cases' . My parents house has a number of rooms where the upstairs radiator is dependent on the downstairs one (as they used open fires for heating the sitting, and didn't need the radiator on there, I spent a lot of my childhood freezing as my bedroom radiator was cold!). This may be typical 1940s plumbing... or just the peculiarities of their house.

Given the amount of overly ambitious DIY done these days, you never quite know what you're going to end up with...

Well I suppose you could connect them in a similar manner to your parent's house - anything is possible, but it is obviously a mistake; the 2 radiators were in effect combined to make one big radiator separated by a pipe!!!

Are you sure the open fire didn't get the room warm enough to operate the wall thermostat and thus switch off the CH pump; so no hot water would circulate. That of course is the big disadvantage of having a thermostat in a living room, when that room is up to temperature, there is no CH in the rest of the house.

mirabelle

Cardew,

I notice you say your central heating pump is running constantly. I have noticed mine doing this. I have a large house (conventional boiler) and turn off half the radiators in rooms not used. Extra heating in Sitting Room is Wood Burning Stove. Would you say its OK the pump running when the boiler is not firing or have I got a faulty pump ? Why does this happen ?

Cardew

mirabelle wrote: »

Cardew,

I notice you say your central heating pump is running constantly. I have noticed mine doing this. I have a large house (conventional boiler) and turn off half the radiators in rooms not used. Extra heating in Sitting Room is Wood Burning Stove. Would you say its OK the pump running when the boiler is not firing or have I got a faulty pump ? Why does this happen ?

Yes it is OK to have the pump running all the time(obviously only when the CH is switched on by the programmer!)

If, as I do, you have your wall thermostat in a cold hall and set it high, then the pump will not turn off because the thermostat is calling for more heat. As stated above the boiler will not fire when the water circulating is up to the temperature set on the boiler.

The pump is obviously using electricity but they use relatively small amounts. Usually between 40W and 100W for older pumps. So if it runs for an extra 5 hours a day(more than a CH system controlled with the room thermostat) that could cost from 2p to 5p a day. Less than £10 a year on average.

Pumps are designed to run for many years without replacement. I am on my second in 21 years. The new breed of modern CH pumps have tiny consumption - as low as 5W.

Again as stated earlier, many older CH systems never had a room thermostat(they are now mandatory) as siting the stat is always a compromise. In a cold hall and that determines the living room temp. In a living room and that controls the rest of the house.

Everything is a compromise, and my compromise, in a big house, of a pump running continually, suits my purpose.

greenbee

Cardew wrote: »

Well I suppose you could connect them in a similar manner to your parent's house - anything is possible, but it is obviously a mistake; the 2 radiators were in effect combined to make one big radiator separated by a pipe!!!

Are you sure the open fire didn't get the room warm enough to operate the wall thermostat and thus switch off the CH pump; so no hot water would circulate. That of course is the big disadvantage of having a thermostat in a living room, when that room is up to temperature, there is no CH in the rest of the house.

Wall thermostat??? what wall thermostat This a very long, thin 1930s house. Cast iron rads & pipes (1 inch pipes I think), no TRVs or room thermostats and an oil-fired boiler that sounds like the space shuttle preparing for launch!!!

By the time the water has circulated from one end of the house to the other it is cold. We used to run down the hallway from the warm kitchen to the warm living room and try not to let the warm air out!

Mind you, when I was a child it wasn't used much - we had a vast wood stove in the hall that was fed regularly, log fires in the living room, electric heaters and towel rails in the bathrooms, hot water bottles in the bedrooms and a solid fuel aga in the kitchen. The bathrooms and kitchen still have no central heating, but the aga is at least oil fired and the central heating is used in place of the woodstove... as my parents have got older they've had to do away with the manual labour!

katrina1979

Thanks so much for everyones reply they have been very helpful and quite a few good ideas.

I currently pay £80 per month to Scottish Hydro on a standard tariff and i dont feel we use the gas that much, obviously we are using what we pay for but i just feek this is too expensive. I use 1 hour morn for getting up, 2.5 hours at night for kids bath and bed time and perhaps another 1.5 hours through out the day if its quite cold.

Another question i have is i have a gas fire in my living room which i do not use. Is it possible to take it out and replace it with an electric fire suite attached to the wall but not permantly as the bolier is at the back of the gas fire.:rolleyes:, not sure if this is something that can be done

lucky11_2

God this thread is confusing!
I have one radiator on at the moment, (combi boiler) no room thermostat and have the timer set to come on and off every hour or so in the day, then on for a few hours in the evening. I hope that as I keep only one room heated with the door closed that it'll save me money??