Danfoss TRV

[scrivomcdivo]

Anybody advice me how to remove the head on a Danfoss TRV? My radiator is cold. The entry pipe is boiling hot and the return pipe cold. I have been advised to try and gently tap the 'pin' hidden underneath the cap of the TRV.

I am just struggling to remove the cover off the TRV. The cover is similar to this:

I have tried pulling off the cover and there is a bit of give, but it just springs back into place. I don't want to pull at it too hard just in case.

 

[twgas]

try this nut

 

[scrivomcdivo]

try this nut

Do I have to isolate the water supply before loosening this nut? I don't think that's what I'm looking to do. I'm actually after just 'popping off' the white cap to reveal the underneath

 

[scrivomcdivo]

Here's the actual TRV if this helps. I am assuming it is something to do with the little screw (click on image to enlarge it)



By the way, I'm decorating (before anyone comments on the state of the house )

 

[nickso]

undo the screw and pull it off the trv.

the head looks a bit brittle though. some of the lugs might fall off when you remove it.

 

[twgas]

shame the first pic was a different valve, makes helping a little tricky

 

[scrivomcdivo]

shame the first pic was a different valve, makes helping a little tricky

Sorry about that. Only realised I could email pics from my phone and so, took pic on my phone.

OK, so I managed to get the TRV off (see below). Should I be tapping the pin in or pulling the pin out a little? How long should it be before the radiator warms up?



The rubber interior within the TRV (which pushes the pin in I'm assuming) appears lob-sided and so, I'm wondering if a new TRV may be needed?

UPDATE

So I've checked the pin and it pushes in and springs back out. Radiator doesn't seem to be warming thought. Reckon the TRV could be knackered given its age? Likewise, when I bled the radiator, the cold water only trickled from it. Also, which way should the tap on the outlet on the radiator be turned for 'open'? Clockwise or anticlockwise?

 

[scrivomcdivo]

**Shameless Bump**

Can anybody offer any advice? I have checked the pin in the TRV and it pushes in and out fine but the radiator is still cold. I have pushed the pin in manually for 5 mins but radiator still doesn't warm. Could I need a new TRV?

 

[twgas]

which way should the tap on the outlet on the radiator be turned for 'open'? Clockwise or anticlockwise?

anti-clock for on

 

[twgas]

try turning off all the other rads to push out airlock

 

[JohnD]

if the pin moves, probably not. Pin "out" is "on" But you can buy one for less than £10 if you want. It is unlikely to be a Danfoss or a Drayton at this price, they are probably the best.

See if the valve at the other end works and is open.

balance your rads

Decide if you have a blockage, usually due to sludge.

I think you want to read no, 8 in the Plumbing Forum FAQs & PLUMBING TIPS (look at the top of this page)

 

[scrivomcdivo]

Just switched off the TRVs on the two upstairs radiators and left on the TRV on the cold one, making sure the outlet valve on the radiator is open. I'll let you know how I get on........

 

[namsag]

The pin on these sit within a housing so it will move without the valve opening as you have found.. undo and remove the nut the pin comes through. under neath in the valve you will see little bit of brass with a hole in it flick this free with an electricians screw driver.
You will get a tiny bit off water so have a towel ready, as you flick it free quickly put nut with pin back on..