Plumbing Nightmare

I mentioned in an earlier blog that part of the work we are doing to the old house upstairs, includes remodelling the airing cupboard. It used to have a hot water tank in it (before we arrived), but when it was removed, the pipework was all left in situ. This picture shows the cold water pipe that rises on the left before disappearing back down through the floor in two places :

Before the weekend this pipework co-habited with a similar arrangement for the hot water. The plan was to get all this pipework re-aligned below the floor, and a start made on lining the cupboard with T&G timber.

Many of my readers will know that I have done a lot of plumbing in my time (e.g. installed two complete central heating systems), so I ought to know what I am doing. However, it became a complete nightmare. I started with the hot water pipes on Saturday afternoon. An old 3/4" pipe leads to the bath tap, and this was cut just inside the stud wall. I knew it was going to be a problem as 3/4" pipe is slightly smaller than the modern 22mm equivalent and the elbow-fitting was a very loose fit on that side. Still, I continued, drilling a hole down into the boiler cupboard below, cutting out all the above-floor pipework, and reconnecting to the feed from the boiler, and the run to the kitchen, below floor.

Needless to say, when I refilled with water, the junction with the 3/4" pipe was no good. There was also, surprisingly, a small weep in one of the 15mm tee-pieces in the new pipework. Everything was drained down again (a process that involves contorting my face around the hot tap in the bathroom and attempting to blow the residual water out of a loosened union under the boiler !).

I replaced the 3/4" to 22mm elbow with a compression fitting rescued from the old pipework. The old olive was carefully eased off the pipe so it could be re-used on the 3/4" side, and a brand new one used on the 22mm side. The T&G cladding will be removably screwed to give access to the back of the shower, so this compression fitting will be accessible too. The compression fitting is shown in this picture :

The capped-off standing pipe is to allow for a hot-water feed to the shower, should we ever decide to replace the rather naff electric one with something powered off the boiler (mains pressure hot water). I also tried to re-make the weeping joint on the tee, as it wasn't too bad and I thought I might get away with just melting the joint and adding a bit more solder.

Re-filling again, the compression fitting was fine, but the process of removing the soldered elbow had dislodged one of the adjacent joints, which was now leaking. At the same time, the weeping tee was now worse.

By now it was 19:00 and I was given permission by the rest of the household to leave the hot water off for the night.

On Sunday, Adam assisted in completely removing the dodgy tee-fitting, and I polished up the pipe ends to fit a new one. I should say, at this point, that, being a bit of a skinflint, I long ago graduated to the cheep-and cheerful bulk sack of simple copper fittings. No solder-rings for me - just plain copper, some flux and feed in my own solder when it is hot enough. It has never been a problem before...... However, replacing this tee, making all the joints again - same problem.

I am well aware that one of the big problems with working on pipework that has been filled is residual water. If the inside of the pipe that you are trying to solder has any water in it at all, it carries the heat away and you will never get a successful joint. I thought I had been very careful to get the water out, by tapping , gently sloping the pipes, and the afore-mentioned blowing down the tap technique. I did not, therefore think this was the problem. Instead I decided that my 18 year old pot of flux had to go, so a trip to the DIY store was made to purchase a new one. Whilst there, I also swallowed my pride and bought a small selection of solder-ring fittings.

Back at home, once more the joint was "un-made", pipes polished, new flux applied and a solder-ring tee joint made. Again, however, unbelievably there was a leak. By now I am getting very exasperated. I am supposed to have finished the cold water circuit by now too.

Jan suggested that I perhaps had more water in the joint than I thought, and that I should try harder to dry it off e.g. with kitchen paper rolled up and eased as far as possible down the pipe ends. I was also becoming concerned about continually re-making the joints with the same pipe ends. For my final attempt I cut out the joint altogether, and made up the solder-ring tee-piece with new pipe, on the bench. I then re-inserted it using three straight couplings, having first used all methods of removing water from the existing pipes, including the kitchen paper method.

Fortunately, this time it worked, though by now it was around 18:00 on Sunday. This was supposed to be Saturday's job ! The finished section under the floor (viewed from below) looks like this :

I am not sure there was anything wrong with the old flux paste, but I have thrown it out anyway. The new stuff looks very different, and seems to work.

I now have to find a time to do the cold-water pipes. Doing without cold water for two days is not quite as acceptable..... Christmas day perhaps ?