Flexible conduit for AV wiring that connects to brush plate?

[Halloway]

I'm planning to mount a TV on a chimney breast and am trying to work out the best way to hide the cables (a power cable, HDMI, and possible an Ethernet cable.) What I picture in my mind is putting two holes in the chimney, one behind the TV and one at the side and connecting the two with some kind of flexible conduit, perhaps 40mm or 50mm in diameter. The ends of the conduit would then connect to brush plates or similar, in much the same manner that you might connect a tumble dryer vent to a vent wall plate. The idea is that I am future-proofing the installation to a certain extent so that I could remove or install different cables sometime in the future without having the knock the chimney breast around.

Trouble is, after literally minutes of googling, I can't actually find such a thing. I can find the brush plates and the conduit no problem but nothing apparently that ties the two together. Is there such a thing?

 

[SFK]

Halloway,
I have not seen what you describe.
But I would make the 'cable duct' from 50mm solvent weld waste pipe.
https://www.screwfix.com/c/heating-plumbing/waste-pipe-fittings/cat831524
I would use this over flexible pipe as will be easier to pull cables through later.

Of course I should highlight the risk of someone in the future forgetting about the cable pipe and starting a fire in the fireplace.
SFK

 

[Lucid]

Most of the sort of round PVC flexi-conduit I think you're talking about is used at surface level. For that reason the junction boxes are surface mount too. They're pattress boxes with the round knock-out holes to take a connection gland. This all works fine when running twin & earth because the cable isn't terminated. Also, it's unlikely that you'll repull T&E. That's not the case here though.

For a start, HDMI cables have plug ends moulded on. They won't fit through the gland size used for domestic conduit unless you go to 32mm which then limits the conduit to 32mm as well. On top of that, once there are other cables in the pipe and gland there's no chance you'll be able to pull a bulky plug end through; you'll either have to empty the rest of the cables first.

The way I do it is using rectangular profile mini-trunking or standard trunking. A 40x100mm profile gives enough space to house several cables and yet still pull a bulky connector. The flatter profile helps when chasing out for concealment. With a bit of surgery, standard metal or plastic back-boxes can be used. They'll need to be deep enough to clear the conduit thickness. What you're doing then is butting up the end of the conduit against one of the four sides of the back-box. Beware if coming in from the left or right because the faceplate fixings will be in the way.

Final point, it's really hard to pull rubber or pVC coated cable through a 90 degree bend in a PVC conduit. The force vectors are wrong and you've also got a lot of friction. There's a risk of breaking the connection wires. Make any bends on the conduit no more than 45 degree at a time. Use silicon spray to lubricate and help reduce friction.

If at all possible, run your power cable in a separate conduit with a gap between it and the signal cables of at least 9". Signal cables can pick up noise from power cables is they're running parallel. the distance gap helps reduce that problem.