Of Mice and Pipes...

[Roger Moss]

I finally got my central heating up and running in mid December, all nicely pressurised and no leaks. Left it running for a few weeks, came back and ... no pressure! (I hadn't left the pressurisation on as there's no cold system yet to supply it).

It took about 35 litres to fill it up again. No sign of leaks at any of the joints. Next day it took another 3 litres. Absolutely no sign of leaks or wetness anywhere. This was a bit worrying! Was it (a) leaking inside the HW tank, (b) leaking from the only joint I couldn't see - buried inside a solid wall?

After a lot of feeling around I found water coming down behind the dry-lining on an external wall - it dripped outside the concrete floor and disappeared amidst the stone-work. Ripping off the plasterboard showed.....an awful lot of nibbled pipe insulation and, under that, a very neatly nibbled oval in the side of the Hep2O pipe, just deep enough to drip once a second or so.

Moral: don't use foam insulation on plastic pipes! Use loft insulation instead, it is probably less tasty.

Is this a common problem? Perhaps the FAQs should mention it. Roger.

[Dave Plowman (News)]

I've heard of rodent damage to cables, but not pipes. Although perhaps the plastic is similar?

My moral would be to use copper. ;-)

[Grunff]

Was it barrier pipe? The PEX pipe I used is so hard that it would take a hell of a lot of nibbling, by a very determined rodent, to get through. Or was it the single layer grey pipe?

[Aidan]

perhaps the

It is a known disadvantage of plastic pipes. I believe that most, if not all, of the manufacturers' installation instructions mention it. The mice don't eat it, they gnaw it to sharpen their incisors. They gnaw cables for the same reason.

And the mice.

[S Viemeister]

AN uncle of mine had that happen - to the cables AND the pipes!

Sheila

[Roger Moss]

As far as I know it was just ordinary Hep2O.

[Grunff]

Tut tut - you should always use barrier pipe for CH!

[Martin Gill]

We woke up yesterday morning to find water dripping through the hall ceiling. After lifting some floorboards all the joints for the central heating pipes seemed dry, but lifted one more and found a little jet coming from a very neatly gnawed section of Hep2O pipe which the plumber had used. Replacing the section of pipe shouldn't be too bad, keeping the pesky mice (we are still hoping for mice not rats at this point!) away from the rest of the plastic piping would seem to be the bigger problem. Wish we'd specified copper pipe with hindsight.

[Dave Plowman (News)]

Strange thing is the material costs are less with copper. Of course labour will be more with 'difficult' pipe runs.

[Grunff]

I don't think rodent damage is a valid reason not to use plastic. If rodents are chewing through your pipes, they'll also chew through your cables, which is potentially (!) more dangerous. The solution is to get rid of the rodents, not the plastic pipes.

I do understand your reservations Dave, but after using plastic pipe and pushfit in a very harsh lab environment, and seeing how well they cope with this, I'm perfectly happy to use it at home.

[Dave Liquorice]

This is true rodents love to nibble the stuff.

But just great for burrowing into and making a nice snug nest...

You need to keep the mice out. Much easier said than done. B-(

[Dave Liquorice]

Any droppings? Mouse poo is like a small long grain rice kernel, roughly 1.5mm diameter and 4mm long. Rat poo is more like 5mm dia and

10mm+ long again black but generally with visible undigested fiberous content.

The gnaw marks from mice are two parallel cuts total width about no more than 3mm and the longest single cutting stroke being 6mm tops. Rat marks are much bigger.

[The Natural Philosopher]

You reminded me. I had been hearing scratchings in the loft, and set a trap last time I was up there.

BT installing new phone line...

I haven't heard em since. Scratcjhings. BT still haven;t enabled broadband tho :-)

May be time to de-corpse...