1 Rad only working with pump on full

[Danny Ramsdale]

Hi,

Hope someone could give me some advice.

I have 1 radiator in the house in the front room (largest one in the house) which will only heat up when I have the central heating pump turned up to full power.

All others work fine on medium or eco mode. The one not working is stone cold even at the inlet pipe unless the pump is turned right up.

What could be causing this? We have recently had a brand new pump fitted.

Thanks in advance

 

[Chester]

How many rads in house? could be a number of things. Does the problem radiator have a trv on it?

 

[doitmyself]

Why was a new pump fitted?
What make/model was the old pump?
What make/model is the new pump?
Does the problem rad get hot, at normal speed, if other rads are turned off?

 

[Best]

Have you checked if both of the pump valves are full open?
Does the radiator have lockshield and a thermostatic valve and are they open? TRVs can seize.
Also it is possible to have a faulty new pump with these new A rated tat, so don't rule out the pump just because it is brand new