kitchen rad not getting warm, no air lock

[fuzzyone]

ah ok, so i can just use a big pair of pliers and pull the plastic turn valve off?

Then just tighten the nut?

Where the plastic bit as in where you turn to up or down the temp on the radiator.

 

[TonyW2]

Yes---but go easy, you don't want to butcher the plastic moulding or round off the plastic where square bit fits in.
And hold the metal valve body.

 

[vicvapour]

Once you've tightened, run the system and check for leaks for around 20 minutes, if there is any very slight leaks now, you could if the leak is tiny use LSX or an equivalent leak sealer.

Goood luck mate.

Hopefully that should solve it