Can I reduce the heat of my towel rad? Or should it stay fully 'open'

[JohnD]

I can't seem to control the heat with the flow valve on the towel rad. I close it completely, and try and back off in tiny increments, but no heat comes. Then it makes a kind of clunk noise in the valve, and the heat comes through full. Its as if I can't really close it down just a bit

Use the one at the other end.

Also, please post a photo of this valve that clunks.

 

[ianmcd]

Whilst it will not provide perfect heat output control, if the flow into the radiator restricted, it's output is certain to be less, because the water will more opportunity to cool down on it's way through the rad. The downside will be that it will also take longer to heat up from cold. Long term, it does need to be fitted with a TRV.

rubbish, energy in energy out, the temp of the water is the temp set at the boiler, a huge amount of water at 70C is exactly the same as a tiny amount of water at 70C no valve can cool down the water

 

[ianmcd]

Whilst it will not provide perfect heat output control, if the flow into the radiator restricted, it's output is certain to be less, because the water will more opportunity to cool down on it's way through the rad. The downside will be that it will also take longer to heat up from cold. Long term, it does need to be fitted with a TRV.

AGAIN TOTALL RUBBISH

 

[JohnD]

energy in energy out

But if, for example, only one litre per hour of water at 60C flows into the radiator, the amount of energy it contains is limited by the controlled flow.

 

[Harry Bloomfield]

rubbish, energy in energy out, the temp of the water is the temp set at the boiler, a huge amount of water at 70C is exactly the same as a tiny amount of water at 70C no valve can cool down the water

The valve does not cool down the water, the radiator and convection cooling does that. The valve limits the flow, and thus the amount of water, plus heat available to be cooled in the radiator. Turn the valve off - the radiator goes cold, turn it full on it acquires the temperature of the water, between those two points - at the near closed position, it can be made to take of a little less than the full temperature.

Simple, basic physics.

 

[ianmcd]

The valve does not cool down the water, the radiator and convection cooling does that. The valve limits the flow, and thus the amount of water, plus heat available to be cooled in the radiator. Turn the valve off - the radiator goes cold, turn it full on it acquires the temperature of the water, between those two points - at the near closed position, it can be made to take of a little less than the full temperature.

Simple, basic physics.

Nope absolutely total bull

 

[JohnD]

But if, for example, only one litre per hour of water at 60C flows into the radiator, the amount of energy it contains is limited by the controlled flow.

Do you say that is not true?

 

[Harry Bloomfield]

Nope absolutely total bull

The systems you install, must defy the laws of physics..

 

[ianmcd]

The systems you install, must defy the laws of physics..

who said I install anything ?

 

[Harry Bloomfield]

who said I install anything ?

So you are trying to convince us that on the opposite hand - that the speed/amount of water flowing through a boiler, makes absolutely no difference to the temperature of the water exiting it too?