Low temperature flow radiators

anon_ymous

matelodave said:

The amount of heat a radiator can deliver to a room is determined by the temperature of the water flowing through it, the material its made of (copper is better than aluminium which is better than steel), it's effective surface area and the temperature difference between the room temp and radiator temp (called Delta T)

So to get the same amount of heat from it at a lower flow temperature (ie reduce the Delta T) you have to increase it's surface area, either by adding lots of fins and/or making it a lot bigger, there is no other magic way of doing it.

Thanks for that. I incorrectly thought that they're 100% efficient but that obviously isn't the case if it isn't all going direct to heat. 

theoretica

waqasahmed said:

matelodave said:

The amount of heat a radiator can deliver to a room is determined by the temperature of the water flowing through it, the material its made of (copper is better than aluminium which is better than steel), it's effective surface area and the temperature difference between the room temp and radiator temp (called Delta T)

So to get the same amount of heat from it at a lower flow temperature (ie reduce the Delta T) you have to increase it's surface area, either by adding lots of fins and/or making it a lot bigger, there is no other magic way of doing it.

Thanks for that. I incorrectly thought that they're 100% efficient but that obviously isn't the case if it isn't all going direct to heat. 

I think it is 'efficiency' being used in a slightly different way - how good they are at warming the room (and so on for less time) rather than energy being wasted in them. 

QrizB

theoretica said:

waqasahmed said:

matelodave said:

The amount of heat a radiator can deliver to a room is determined by the temperature of the water flowing through it, the material its made of (copper is better than aluminium which is better than steel), it's effective surface area and the temperature difference between the room temp and radiator temp (called Delta T)

So to get the same amount of heat from it at a lower flow temperature (ie reduce the Delta T) you have to increase it's surface area, either by adding lots of fins and/or making it a lot bigger, there is no other magic way of doing it.

Thanks for that. I incorrectly thought that they're 100% efficient but that obviously isn't the case if it isn't all going direct to heat. 

I think it is 'efficiency' being used in a slightly different way - how good they are at warming the room (and so on for less time) rather than energy being wasted in them. 

Yes, all the energy that comes out of the radiator will go ito the room; the efficiency is the same.

What differs is how many watts you get from each square metre of hot metal.

anon_ymous

QrizB said:

theoretica said:

waqasahmed said:

matelodave said:

The amount of heat a radiator can deliver to a room is determined by the temperature of the water flowing through it, the material its made of (copper is better than aluminium which is better than steel), it's effective surface area and the temperature difference between the room temp and radiator temp (called Delta T)

So to get the same amount of heat from it at a lower flow temperature (ie reduce the Delta T) you have to increase it's surface area, either by adding lots of fins and/or making it a lot bigger, there is no other magic way of doing it.

Thanks for that. I incorrectly thought that they're 100% efficient but that obviously isn't the case if it isn't all going direct to heat. 

I think it is 'efficiency' being used in a slightly different way - how good they are at warming the room (and so on for less time) rather than energy being wasted in them. 

Yes, all the energy that comes out of the radiator will go ito the room; the efficiency is the same.

What differs is how many watts you get from each square metre of hot metal.

Thanks. Are these guys a decent company then for that?

https://www.evergreenenergy.co.uk/heat-pumps/do-i-need-bigger-radiators-to-have-a-heat-pump/

6% savings certainly adds up. Not something for now but something for the future, sure. 

Reed_Richards

Any half-competent plumber can replace an old radiator with a new one.  The better plumbers will achieve this without getting dirty water all over the carpet and the poorer plumbers will make a mess.  The hard part is working out what "size" of radiator you need to keep the room warm enough whilst reducing the water flow temperature to improve your efficiency.