Radiator thermostat won't turn off

[Reesy09]

Hello,

I am a complete novice and need help with a radiator thermostat I have that will not let me turn the radiator onto the frost setting. I think it's a Danfoss thermostat RAS C2. The plastic thermostat comes off when I pull it and I can see an arrow on the brass valve attached to the radiator. I don't know whether the thermostat is working, although it seems to turn ok, but don't know which way to put it back onto the brass valve.

I know absolutely nothing about radiators and desperately need the radiator to turn off as I have a woodburner in the room and it's too hot in here!

Thanks in advance.

 

[yerino]

Can you not turn it off on the other end (Lockshield)?

Pull off the little white cap and turn the little valve completely clockwise.

 

[Reesy09]

There isn't a white cap on the other end or a little valve that I can see. I need to be able to control the temperature of the rad though as I don't always have the woodburner lit, so it needs to be on sometimes.

 

[yerino]

Well firstly you need to establish if the valve is working!

If it's not working you will need to get it replaced.

 

[JohnD]

you say you have a woodburner?

maybe it has been fitted with stops to prevent it being turned off (so that it will absorb excess heat and prevent the boiler... boiling)

how far does the head turn in each direction?

The Danfoss lockshied is extremely small. Can you post a pic of what is at each end?

 

[Reesy09]

How do I do know if the valve is working?

 

[Reesy09]

Here are the photos[/img]

 

[Reesy09]

View media item 27191 View media item 27190

 

[JohnD]

the thing on the right is the lockshield. you undo the chrome nut on the top (no water will come out) and put a small tool like an allen key down the hole to adjust it or turn off.

Neat, isn't it?

 

[Reesy09]

Great. Thanks John. At least I should be able to turn the thing off at least.

I've just realised though that when I said the thermostat won't turn to frost, I meant that although it physically turns to frost, the radiator doesn't respond. I think the plastic part is not pushed onto the chrome bit in the right way. Which way should it be aligned?

 

[JohnD]

by chance I have a box of these TRVs next to me.

you say the plastic thermostatic head comes off when you pull it.

turn the top to the highest setting (anticlockwise seen from above)

the plastic rib on the lower half should line up with the arrow shaped mark.

screw the grey ring up into the body of the top part (this opens the grippers)

push the thermostatic head onto the brass valve with the plastic rib facing you, and hold it there, pressing it down.

screw the grey ring downwards as far as you can. jiggle the plastic top and tighten some more. This tightens the plastic gripper onto the brass valve.

It should now be firmly fitted. Turn the knob and check that the grey ring is fully down and tight.

you can now turn the top part of the thermostatic head. it will rise slightly as you turn it to the hotter settings.

 

[Reesy09]

Thanks John, those instructions were great. I've secured the plastic bit now, but the heating is off so will wait until tomorrow to check it works. Thanks for making it so straightforward for me! I really appreciate your time.

 

[Reesy09]

A assume the brass valve be as tight as possible before putting the plastic bit on?

 

[JohnD]

did you set the top to hottest setting before putting back? is it fully seated on the valve? pushed down hard and wiggled, and pressed down while you tightened the ring?

 

[Reesy09]

Yes, I did what you said and then when it didn't work, I took it off again and noticed the brass valve isn't tight. I've tightened it by hand and put the plastic bit back on again, although the plastic rib and arrow are now round the side not facing out. Does this sound right?