TRV question on radiators

psd99 · 22 Dec 2017 at 09:10

Hey guys,

Across the house I have 7 radiators with TRV's

on some of the radiators when I turn the TRV to 3 or 4 nothing comes out of the radiator i/e no heat only if I turn the setting to 5 or 6 it works.

what could be the problem? Do these radiators need bleeding?

topgun06 · 22 Dec 2017 at 09:13

Is the room cold? It could be that the room is sufficiently warm enough at levels 3 and 4 to not open the rad valve.

psd99 · 22 Dec 2017 at 09:17

ah so im reading that the TRV does not control the radiator temperature!

psd99 · 22 Dec 2017 at 09:21

topgun06 said:
Is the room cold? It could be that the room is sufficiently warm enough at levels 3 and 4 to not open the rad valve.

I think the room was fairly warm, it was the kitchen and I was cooking.

topgun06 · 22 Dec 2017 at 09:23

The TRV controls the flow of water into the radiator based on the room temperature. Looks like it is working as normal.

adam1v · 1 Jan 2018 at 22:21

psd99 said:
Hey guys,

Across the house I have 7 radiators with TRV's

on some of the radiators when I turn the TRV to 3 or 4 nothing comes out of the radiator i/e no heat only if I turn the setting to 5 or 6 it works.

what could be the problem? Do these radiators need bleeding?

What sort of system do you have? Daft question but is the central heating on when your opening the valve? What TRVs are you using?

Hedge · 1 Jan 2018 at 22:54

psd99 said:
ah so im reading that the TRV does not control the radiator temperature!

The valve is basically an on / off for the radiator. Water temp is controlled by your boiler thermostat.

psd99 · 2 Jan 2018 at 08:37

adam1v said:
What sort of system do you have? Daft question but is the central heating on when your opening the valve? What TRVs are you using?

system boiler with a megaflow

yes the heating is usually on when I have played about with the TRV, does that make a difference?

I'm using ones from screwfix they probably are not the greatest in all fairness.

psd99 · 2 Jan 2018 at 08:39

Hedge said:
The valve is basically an on / off for the radiator. Water temp is controlled by your boiler thermostat.

that's another bug bone.....

I have a worcester 24kw boiler but I can't seem to change the temperature on the actual boiler it just stays stuck despite pressing the buttons up or down.I think one of them works the other doesn't like heating vs water just can't remember which one works which one doesn't will check tonight.

what's the temperatures supposed to be anyway?

Simon42 · 2 Jan 2018 at 10:52

psd99 said:
what's the temperatures supposed to be anyway?

It depends on the balance between maximum heat output and boiler efficiency. If heating a hot water cylinder then it needs to be enough to kill bacteria in that. A number of non-combi boilers still have settings/dials for hot water on the boiler even though they're not relevant.

I rarely change my boiler from 70 degrees as we set the hot water cylinder thermostat to 65 degrees. Setting the boiler to 65 would make it a little more efficient but not enough to make it worth the slight drop in heating performance.