Leaking radiator (with picture)

[Pillskii]

One of my radiators is leaking, albeit very slowly. I've attached a picture below, the water is dropping from the bottom of the nut. Now I'm not the most hands on, although I feel loath to call out a plumber for what, on the surface, looks like a tiny issue.

Can I just tighten the nut with a wrench and it will stop?

(Picture needs turned 90 degrees clockwise sorry)

[Big Al.]

The bottom of what nut left or right (attached to pipe) in the image?

[Simpo Two]

I'd grab a spanner and 'nip it up'. In other words the lower nut is a compression fitting and tightening it another 1/8th turn might do the job.

(This worked for me when a small clumsy child clouted the rad in their bedroom and made it leak!)

[Pillskii]

Big Al. said:

The bottom of what nut left or right (attached to pipe) in the image?

It's the right hand nut further from the pipe, you can see the drip hanging off the bottom. Sorry it's not very clear!

I'll maybe give it a very slight tighten and see how it reacts. Got fears of water gushing out everywhere.

[Rickyy]

Quick nip up should do it, but support the valve with a pair of grips as you tighten it, slightest bit of movement can dislodge that microbore pipe and cause it to leak!

[dazwalsh]

If you try tighten that you will most likely twist the valve and potentially bend the pipe, so with a pair of water pump pliers or a large expandable wrench grip the top of the valve and hold it vertical whilst you tighten the nut with another wrench.

[B17NNS]

Rickyy said:

Quick nip up should do it, but support the valve with a pair of grips as you tighten it, slightest bit of movement can dislodge that microbore pipe and cause it to leak!

This. Make yourself aware of a drain off point too (and make sure it works) should the worst happen.

[Alucidnation]

If its the "nut" closest to the radiator, you wont tighten that unless you loosen the vale from the stem first.

And even then, you may not have any success as it looks like its fully tight anyway.

These things sometimes leak when there isn't adequate ptfe applied to the adapter threads before its screwed into the rad.

[g7jtk]

Turn both valves off. Open air cock to reduce the pressure. Close it.
Undo the nut and insert some jointing paste. Tighten the nut and open the valves. Job done.
Obviously take precautions to catch any escaping water. There shouldn't be much.

[Sheepshanks]

g7jtk said:

Turn both valves off.

I wonder if the OP has the tool to turn that valve off?

To be honest, as others have suggested, I'm wary when microbore is involved and I regard myself as reasonably capable - I've had it happen that the valve moved suddenly and the compression joint on the microbore let go.