rad valves

[Belle427]

my trvs have lost their adjustability since ive messed around moving rads etc when i gutted my house,as far as i know i re connected all the pipes back to their feed/flow lines but sometimes turning them down to say number 2 and the rads go cold,is there anything i can check?
not sure on numbers but they are danfoss

 

[sime10]

If they go off at number 2 they have reached temeprature Have you got anything like curtains or anything covering the TRV?

 

[Softus]

Remember the old Tommy Cooper gag?

"I went to doctor and said 'Doctor, it hurts when i do this [lifts arm]'.
The doctor said, 'well don't do it then'".

 

[Belle427]

problem is the rads are stone cold on number 2,its mainly the upstairs rads im concerned about,bedrooms are far too hot with them flat out

 

[ChrisR]

They work on the air temp, not the radiator temp. If the room's warm, the rad valves may well not open on 2.

 

[pannierstan]

Oh dear, I feel a lesson in TRV operation coming on for CH427

 

[JohnD]

Try them on 4.

 

[Softus]

Oh dear, I feel a lesson in TRV operation coming on for CH427

Go for it - someone has to.

 

[pannierstan]

Try them on 4.

I would agree. Dont ask me where I remember it from or if I am talking a load of old tosh

In the good old days a 5 position TRV was always 4 at around 20 deg

1 was 5
2 was 10
3 was 15

I know you can never set a figure on them as they are very coursely calibrated, but thats what I have always gone by.

Stan

 

[Belle427]

i used to acheive a good temp in the rooms with them set on 2,now they seem hit and miss,nothing else has changed,would appreciate if anyone knows the correct relation between temp and the numbers

 

[Softus]

If they've become unreliable then you clearly have faulty TRV heads, so just replace them. But if they work on setting "3" instead of "2" then, FFS, just put them on "3" and let's get on with our lives.