How best to blank these pipes at floor level?

banie01

As per the thread title,looking for advice on blanking unused central heating pipes.
I recently moved a rad to prepare for a kitchen renovation/knockthrough and the remaining pipework is capped.
Now I need to get the cap level with the surrounding floor to allow the planned double doors to open, but as the floor is concrete and I do not currently want to change the tiles(and I have no spare tiles to repair any damage to the current tiles so lifting those is out of the question too)
I am just wondering what the best course of action for doing this job would be?
As always, thanks in advance for the advice folks.

freddyuk

Interesting problem and not uncommon. If you really cannot trace the pipes back to a point where you can isolate them effectively then if it was me I would drain the system, ensure it was dry and stuff something a good way down the pipe to block it and then mix some resin to fill the pipe and let it set. As the resin sets it will heat up so should allow for any expansion of the pipe if it subsequently gets hot. Cut off the olive and peen over whats left of the pipe to just below floor level and then finish with a matching mortar to floor level.
You have to make sure the inside of the pipes are clean and dry to ensure water will not weep past.
If it is a pressurised system I would think of something else although it should still hold but your call on that one.

Sparkpea

Sorry I would not be trying to do the above at all.

Your only solid choice in my opinion is to dig down around the pipes a little not making too big of a hole and drain the system, blow down the pipe to push water out and solder a stop end on. Then cement/grout in the hole. I wouldn't be thinking of anything else unless the pipes rise to a manifold where you can disconnect them there.

listermint

Yep lift that tile and dig out around it.

Water will always attempt to find its way through. The LAST thing you want is a hidden leak in the floor. Do it right do it once.

freddyuk

Epoxy resins are used all over the building industry for sealing all sorts of materials in all sorts of temperatures and pressures. Don't just dismiss it because you never tried it. You could do it and leave the pipe proud and then pressure test the system. If it holds it will be fine. Then cut off. Of course the OP may decide to dig up the floor and solder a joint. It will need to be a biggish hole to do that properly. Any sort of water in the pipe will prevent the solder taking so you may end up having problems getting it to seal or removing the end cap to try again.
There will be a thin layer of mortar over the end so any weeps will be easily spotted and dealt with.
Maybe have a chat with professional suppliers of Resins to ask them your best option/product. You will not find a plumber who will advocate it which is understandable but if you are DIY'ing you have the options to try anything you want to avoid ruining your own floor.

banie01

I'm a fan of epoxy myself in many instances but in this case I'm not so sure, as I was/am conscious of the pressure/heat concern.
It is a pressurized system and from past experience water always finds a way.
I was hoping there would be some kind of bung or similar available that would do the job.
So it'll likely be dig a hole and then try keep it small.
Thanks for the advice folks, and anymore will be welcome too

shane0007

Sparkpea wrote: »

Sorry I would not be trying to do the above at all.

Your only solid choice in my opinion is to dig down around the pipes a little not making too big of a hole and drain the system, blow down the pipe to push water out and solder a stop end on. Then cement/grout in the hole. I wouldn't be thinking of anything else unless the pipes rise to a manifold where you can disconnect them there.

Completely agree here except I would not concrete around the pipe/end cap without covering it with insulation or something to separate the concrete from the copper. The cement will eventually eat into the copper & cause a leak.
The existing pipe is surrounded by concrete also so this would definitely be the option.

freddyuk

Well I did say not on a pressurised system. Hopefully the pipes are already in pipe wrap so take out as little as you can around the pipe with a hole saw or if there is pipe wrap dig this out to sufficient depth. All you need is enough room to get a length of solder down to the joint of an end cap. The insulation will melt of course if it is there. Make sure there is no water anywhere in the pipe or you may screw up the joint. Even a little will boil and steam and cause the solder to fail. Clean the copper as best you can and flux. 15mm only takes a few seconds to get hot enough if there is no moisture present. Use a decent torch with a small flame and hot. Get the solder in there and don't worry about wiping the joint. Clean any flux off with a damp cloth.
Good luck.