Modifying radiator pipe position under floor void

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I am looking to move a radiator from the rear wall (under window) to the side wall within the room as I am installing french doors.

Ironically, this was the previous position of the radiator. As I result, the holes are pre-drilled into the floor and I am positive the pipes are just below.

Rather than lifting up the floor boards (tongue and groove), the void beneath the ground floor is pretty decent (around 60-70cm).

After going under myself and crouch walking to the correct location I found that, as suspected, the pipe work was cut at the old rad positions and extended with compression valves. It is the last radiator in the run it seems as it only has two pipes directly feeding each side. They do not branch off any other pipework. Is that common with the last radiator in the run?

So, If I felt I could do the work myself I would need to

1)Drain the system
2)Cut the existing pipework ensuring the existing holes are directly above. If this lines up with the compression joints, so much the better.
3) Fit elbow compression joints
4)Poke up the copper pipework and fit to the elbow joints.
5)Ensure the pipe work is secure (retaining clips to joists or wall).
6)Re-attach Rad in new position.
7)Fill system

Anything I have missed or should look out for.

It looks as if the radiators was moved position via the void last time. The floorboards have no damage and the compression packets were left in the void as well as spare pipe.

If I felt that I was in over my head, my additional questions is....how many plumbers are prepared to go into a void to do work? Would this be refused as an option? I only ask as I prefer this to cutting up a floorboard.

Many Thanks in advance
 
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Doggit

The only thing you've missed from the list, is fill system and add inhibitor, otherwise your plan is fine.

As to a plumber going down into the void, all you can do is ask them, and then see how much they'll charge to do it that way. but looking at how you worked everything out, I suspect you can do this yourself. Take a cushion and dust sheet down there with you.
 
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The only thing you've missed from the list, is fill system and add inhibitor, otherwise your plan is fine.

As to a plumber going down into the void, all you can do is ask them, and then see how much they'll charge to do it that way. but looking at how you worked everything out, I suspect you can do this yourself. Take a cushion and dust sheet down there with you.

He is moving a pipe FFS, not going to sleep !!
 
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Doggit

Now how do you know, are you psychic. It's totally up to him, but he'll be slower than a plumber, and he'll very likely be on his back a lot of the time working upwards - I'm just thinking of his well being, okay, maybe the cushions overkill.
 
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So is the Dust sheet.
It will hide all the nasty sharp things he could kneel on.

A fookin lead lamp would be better advice.
 
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Thanks for the advice.

There maybe enough space to sit crossed legged. I am pretty slight so it should not be too uncomfortable. Appreciate the cushion idea, although some knee pads are something to consider.

I was unsure whether even asking a plumber to go into the void was a good idea hence testing the opinion on here.

But...as you say.....it seems simple enough as long as I do everything in the correct order.
 
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It will be a lot easier if you can recruit someone to work topside, so you can pass pipe through for him to hold or fit into the valves. Or give him 2 pipe clips to clip to pipe temporarily to stop them falling back through
 
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You'll probably find that most plumbers now won't go under. When I was apprenticed ( 1970's) I spent days under floors and up in roofspaces wrapping hair felt lagging - I'm 6 foot 2 and was 13 stone back then - but I was keen. Deffo use knee pads. My knees are b'ggured with arthritis because I didn't.
 
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Plumbers not prepared to work in cramped or uncomfortable places?

FFS

99% of all plumbing work is other than ergonomically ideal!
 
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I have often done underfloor work but I know that many others will not be that keen. 5' 9" and 84 kg so average size.

I can give some advice!


Firstly connect tube to rad so it protrudes down to underfloor ready to be connected to.

Wear thick overalls.

Go to toilet before, just in case!

DO take an old cushion or have a hood on the overall so that you can comfortably lie on your back without having to hold your head up.

Ideally wear a hard hat. There can be nails protruding through the floor and you don't want to seriously cut yourself on them. Even so still move slowly.

ALWAYS have a second person on the floor in case you get stuck or any other problem.

Have TWO light sources, ideally a mains leadlight AND a small torch as a reserve.

Tony
 
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Thank you for the advice.

I have drained the rad in question, seemingly, whoever put it in did not retain the pipes well as they want to drop throught he floor. Only the valves are keeping them up.

Just need to drain the whole system now. There is no drain cock on the system, so am using the hosepipe technique.

I just need to ensure I get the correct valve to isolate the feed to the central heating. There is a valve that is positioned after the three-way valve/port. This is on the opposite side to the leg that heats the tank, and it is not the run (comes up from the below) that I think comes from the boiler. So I assume this feeds the central heating circuit. I therefore assume if I close this valve, the central heating system will be isolated and drain? Correct?
 
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No. Tie up the ballcock on the small tank in the loft.

(I'm assuming yours is an open system)
 
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Indeed it is an open system - I was aware that I could do that but I thought getting the correct valve might be even easier/less hassle.
 
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Update:

OK, got all the tools, pipe cutter, de-burrer, plumbers paste etc. The system is drained and I have put down to pvc matting so the crawl to the required location is a very clean and comfortable experience now.

Tomorrow I shall cut the pipes at the required locations and put the elbows in. Get someone to lower the existing pipes with valves on the end and put it all together.

I guess the only downside is that I have to watch the new joints when I refill the system. I have also just noticed the elbows I got from screwfix look to have brass olives. I have been told copper ones are much better. Is this true?

One further question. The current radiator is 600mm by 1400mm single panel with convector fins. The existing hole for the rad pipes is about 1.5cm away from the skirting and the skirting thickness is 2.5cm. If I replace the radiator with a double convector, is this hole too near the skirting and/or wall. I assume I could ensure there is enough pipe to ensure the radiator is above the skirting, which would give 4cm of room. Thoughts?

The room is about 3.7m by 4m, is a single convector enough maybe?
 
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