Drayton TRV4 numbers to temperatures

[Graphite]

If those values are correct it is a good starting point, so that people have some idea what they are dealing with.

It is good to have some idea of the ballpark that the TRV is tuned to.

With my first experimenting with mine I have found on one that 3 is turning the rad off at about 18ºC, at 3.5 it is currently at 19ºC - so not a 5ºC leap as the previous poster suggested.

I am experimenting with mine but I would like some feedback on the results others are getting.

As for resurrecting old posts - I came acrosss this one via google - it would seem pointless to start a new thread summarising what went on on this thread when the info is already here.

 

[Agile]

You have been selective with your reading!

Carry on being blinkered if it makes you feel better.

If you want to understand the situation in more detail then read all the posts ( particularly mine ) and try to understand whats going on.

To help you with such a difficult subject for you try to understand, the TRV is close beside a rad at about 60°C with the room at about 21°C on the other side.!

Tony

 

[Graphite]

A bit caustic Tony

I'm well aware of the huge permutations of fluid dynamics that can occur in this situation...

But a ballpark figure to work from is often all that is required in these sort of situations to get a good starting point

We don't need a CFD analysis of each and every radiator and the surrounding area, but to know that at setting 1 the TRV will turn off at 10ºC I would submit is quite a helpful thing to know

 

[Agile]

I would say that its pretty irrelevant!

The only setting you need to be aware of, as a user, is the setting which gives you a comfortable temperature, thats "about 3".

The fact that the valve may be half closed when the head is at 25° is of no relevance because the temperature where the valve is situated is determined by the layout and temperature of the radiator and pipework and to a lesser extent by the room temperature. It will also be greatly determined by the thermal convection currents in the room which are determined by heat losses and layout.

Tony

 

[thermoman1]

i have removed one of these valves from an unused radiator. i cant comment
on the higher temperatures but on the low end the numbers on the dial correspond to:

"1" opens at 15degC
halfway between "1" and the snowflake opens at 13degC
the snowflake opens at and below 11.5degC

my problem is i have a guest bedroom with 3 external walls that i dont want to heat at all unless we have a guest.
even on the snowflake setting, when the weather is cold this valve opens and slowly leaks heat into the room until it warms itself up to 11-12degC.

i guess ill have to turn it off at the lockshield valve.....

 

[chatmandu]

my problem is i have a guest bedroom with 3 external walls that i dont want to heat at all unless we have a guest.
even on the snowflake setting, when the weather is cold this valve opens and slowly leaks heat into the room until it warms itself up to 11-12degC.

i guess ill have to turn it off at the lockshield valve.....

If you think about it, by having that room so cold, you're turning your internal walls into external walls from a Delta T perspective. Your other rooms, that share walls with it, will experience excessive heat loss. They will also likely have less thermal mass and insulation, than the external walls, so it might be worse than the heat loss experienced through the external walls.

I think you might as well just heat the room.