Thermostatic valves for radiators

uberalles

Good morning all,

I have a quick question that may come across as me being a little dumb but it is one I have been trying to come to terms with. Here goes:-

Oil central heating in a house of 4000 square feet, spread over 2 levels.

14 Radiators in total and I have been quoted circa £550 total to have TVRs fitted on each of them.

We use everyday only 5 rooms out of a total of 11, therefore only 6 radiators out of 14.

So my question is, whilst we have the heating on, does it make much difference financially to have TVRs fitted considering the initial outlay of circa £550.

My way of thinking, including why I cannot see where the financial value would lay, is that the water gets heated all the way up to each radiator in the pipes, then the other side of each radiator, so therefore the only water in the system not being heated is that in the radiators that have the TVR set at a temperature lower than the room temperature.

I would have thought that the radiators would not have held a significant amount of water. Am I wrong?

For example, how much water would a radiator, about 6 feet wide and 2 feet high, hold compared to let's say a 10 metre length of piping.

The rooms we seldom use would have the radiators heated to a relatively low temperature to ensure damp does not occur.

Thanks for reading, your patience , and any responses.

ormus

in such a large house with oil heating id be looking into splitting the house into two CH zones.
that way one zone could be switched off virtually all the time.

1984ReturnsForReal_2

The money saving comes from the temperature of the water flowing back into the boiler & the electrical cost to pump it.

The more the system is shut down the higher the water temperature coming back into the boiler therefore the less energy it uses in the heating process.

uberalles

ormus wrote: »

in such a large house with oil heating id be looking into splitting the house into two CH zones.
that way one zone could be switched off virtually all the time.

Ormus, thank you very much. I actually had that same idea a while back but strangely enough, :think::undecided , the fella who quoted stated that TVRs was the way forward. Thanks again , I am going to reconsider that same option.

1984ReturnsForReal wrote: »

The money saving comes from the temperature of the water flowing back into the boiler & the electrical cost to pump it.

The more the system is shut down the higher the water temperature coming back into the boiler therefore the less energy it uses in the heating process.

1984ReturnsForReal, thank you too. What you have mentioned makes perfect sense. I didn't consider the obvious fact that the system works on a constant loop of flowing water through the boiler, heating it to a required temperature all the time. Thanks again.

1984ReturnsForReal_2

uberalles wrote: »

1984ReturnsForReal, thank you too. What you have mentioned makes perfect sense. I didn't consider the obvious fact that the system works on a constant loop of flowing water through the boiler, heating it to a required temperature all the time. Thanks again.

That is the most important bit.

DVardysShadow

ormus wrote: »

in such a large house with oil heating id be looking into splitting the house into two CH zones.
that way one zone could be switched off virtually all the time.

I'm not so sure. If you are considering putting in a system, this would be worth thinking about. But for an existing system, the pipework may not be laid out right to get the zones you want easily, leading to a substantial replumbing job.

TRV's will meet the OP's requirement for background heating to keep the damp off, whereas a zoned system will only turn the zone on or off. And TRV's are much more flexible in that you can choose whether to put a room in the heated or damp controlled zone on a day by day basis.

uberalles: don't forget, if you have a room thermostat, you should not have TRV's in that room.

inmypocketnottheirs

Also bear in mind that if a single pipe system is installed and TRV's are fitted, if a rad is turned off, then all the radiators further along the system will also be closed.

A lot of plumbers when giving advice to the customer often only think what is best for them as they will have to do the work. This does not always translate to the best advice for the customer.

dander

I was very doubtful about the point of TRVs on virtually every radiator when my plumber decided to install my heating that way, but actually I find them very useful - not so much for financial reasons, but just because different rooms with different numbers of radiators/windows/outside walls heat up and hold the heat differently. The TRVs make it easier to get a balance of heat across the house.

uberalles

DVardysShadow wrote: »

I'm not so sure. If you are considering putting in a system, this would be worth thinking about. But for an existing system, the pipework may not be laid out right to get the zones you want easily, leading to a substantial replumbing job.

TRV's will meet the OP's requirement for background heating to keep the damp off, whereas a zoned system will only turn the zone on or off. And TRV's are much more flexible in that you can choose whether to put a room in the heated or damp controlled zone on a day by day basis.

uberalles: don't forget, if you have a room thermostat, you should not have TRV's in that room.

Thank you. Unfortunately we only have the one Thermostat which happens to be on the boiler. So you choose what temperature you want the heat to be on the boiler and then it happily heats all the radiators. I have found a temperature that does the job for all radiators, some getting hotter than others but all fine, but I sometimes wonder about the validity of it's reading as it is quite low on the dial.

The boiler is, I am told, at least 8 years old so when it comes to a new system I am seriously thinking about installing a wood boiling system only. This will depend on how long we choose to stay here as I know it will not suit everyone should we come to sell, but we are next door to woods that we have access to and there is a timber yard where I buy wood for the living room stove at £12 a half ton.

inmypocketnottheirs wrote: »

Also bear in mind that if a single pipe system is installed and TRV's are fitted, if a rad is turned off, then all the radiators further along the system will also be closed.

A lot of plumbers when giving advice to the customer often only think what is best for them as they will have to do the work. This does not always translate to the best advice for the customer.

Thank you, I didn't consider that either. I know there are at least two pipes but I guess that could constitute an outlet pipe and a return pipe. Couldn't it? (I'm unsure).

I also appreciate what you mention about the plumbers advice, that makes good sense.

DVardysShadow

uberalles wrote: »

... Unfortunately we only have the one Thermostat which happens to be on the boiler. So you choose what temperature you want the heat to be on the boiler and then it happily heats all the radiators. I have found a temperature that does the job for all radiators, some getting hotter than others but all fine, but I sometimes wonder about the validity of it's reading as it is quite low on the dial. ...

The boiler thermostat is quite valid. Bear in mind if you have a full set of thermostatic valves, you maybe should run near max temp - and probably should have a rad left fully on, without a TRV

keystone

And the quoted price seems rather high BTW. You really should have a roomstat as well.

Cheers