Will i get better heat output and warmer rooms if i replace rads

Passport1

Hi
Typical semi d house about 20 years old

Last winter the rooms(Particulary the hall and the sitting room) seemed very cold even with the TRV on the rads at highest settings and stat at 20 degreees or set higher - 25 degrees during the really cold spell

The rads themselves would be very hot -so not case of them airlocked

Attic was re-insulated last year to bring it up to 30cm insulation standard or whatever the standard was and boiler for heating was replaced and whole system was flushed out at that time so no air locks in rads and rads heating up well

The walls are hollow block constuction so cant pump insulatation into them. Cant really put external insulation on outside walls as house will look out of place with outjoining house

If were to put internal isulation - will lose too much space on internal room sizes and cant afford to lose that space of room size

The windows are double glazed

The radiators in most of the rooms are the single radiators - there probably since the house was built

If i was to replace the rads with newer rads in some/all of the rooms - like the newer double rads would that give better heat output into the rooms and make the rooms feel hotter/warmer and be more energy efficient or would that be just a waste of money and the current rads are fine
and its down to the insulation in the walls and also last winter really extreme temps

Thanks

Outkast_IRE

Well you dont just replace all singles with doubles and think that will do ,
what you need to do is get the rad calculator or a competent plumber to work out what the proper heat requirements for each room are and then work from there .

Some people will then ask you to oversize the rad slightly just to be safe if they are worried about it. Which can be done but just swapping all singles to doubles isnt necessary.
Just work out your calculations for each room and work from there , the new singles would be more efficent than 20 year old singles and have a higher heat output .

Micky Dolenz

May have more to do with external factors such as insulation and draughts.

Sparkpea

New rads should be more efficent because u won't need as big a double rad to heat a room, for example I was able to change a 21x101 single panel with a new 21x45 double panel convector which was less water to heat but also gave out more heat output. I also powerflushed the system and installed a new water circulating pump. I was able to turn the boiler temp down 5 degrees and the client still said the heat in all the radiators was 10 times better than it was.

That was only one rad replaced but the rest of the system flushed so a combination of all 3 worked well.

yoshytoshy

Don't put in radiators that are too big ,it will end up costing you unnecessarily.

Get things calculated ,it's possible as micky said that it's a heatloss issue ,rather than an output one.

Also ask around about powerflushing ,you could get your system cleaned and just one or two radiators installed.

Alex M

trv thermostat is sitting right beside the rad, in extreme cold you may need to keep the room at 20 - 25 degrees but the trv will keep shutting at the the rad when this temp is reached, the other side of the room may be cooler. mabe remove the trv head tempory to allow the rad , and in turn the room, keep heating