once again into the breach....

[Ireland House]

Most pex systems seem to run to a manifold then they all feed from that From a larger diameter supply. I once saw a guy that ran pex in a loop. It’s fed from two directions. His theory was that if it's run in a loop and then if anyone takes water from anywhere in the loop it’s being fed in two directions. No manifold needed. I found it interesting to think about[/quote]


The manifold really paid off this week. One of the new shut off valves failed and we were able to just isolate that loop from the manifold and not loose the water to the rest of the house!

[phil]

I have a line where they just put epoxy on the pipe where it was leaking and wrapped it with tin foil. It worked while they owned the house. I cut the line off as it feeds an outside tap I can do without for now.

with pex, I understand it can withstand some freezing. in some houses that are plumbed right the lines slope so you can drain them should you need to winterize. with pex it is harder to get that sort of slope but I guess maybe the dips don't matter so much since it can expand a little without rupturing at least the first time it happens. I'm still a little leery about weather it could take a situation where it froze and thawed a lot such as might be the case in a house that isn't heated during winter weather. With our summer place it is a major undertaking to drain all the low spots, toilets, traps etc , then in spring there is inevitably a leak where we missed. In most of our houses we heat year round of course so that is never an issue. There we do not glue the traps under each sink on so we can pull them apart that way people don't forget they are winterized and dump water down the sink.
its quick to fix too , you can cut and join new stuff in so easily. At first I had some hesitation to use plastic thinking it wouldn't last so well but I think plastic just got a bad rep as some of the very first types didn't' have good longevity, the plastic sort of rotted over time.

I think the brass fittings , some might not really be brass but a shiny alloy with brass in it and who knows what else? I wonder if hard water will attack that in time or if it is OK. Its kind of hard to know by looking at it when it's new. A local plumber would know best.

my sister owned a house that had copper, but back when it was made it was thinner than it was supposed to be. The company that made it was saving copper and years later the issue came to light as they rotted out faster than expected. there was news about lawsuits years ago.

I was later trying to do some splices at the summer property.. dad had picked up this weird sized copper. Metric? it was close to half inch but not exactly. I didn't know if it was the same thing but regular fittings didn't fit although it appeared to be 1/2". After becoming frustrated trying to solder to the stuff, The solder didn't want to stick.. maybe just too old and impure metal.. we have re-used fittings many times before so we know how to work with old fittings but this stuff just would not tin properly..

To get things going, we stuck a bit of rubber hose and some hose clamps on it but it should be re-plumbed. That was what I'd call a "farmer repair"

[Gothichome]

Most pex systems seem to run to a manifold then they all feed from that From a larger diameter supply. I once saw a guy that ran pex in a loop. It’s fed from two directions. His theory was that if it's run in a loop and then if anyone takes water from anywhere in the loop it’s being fed in two directions. No manifold needed. I found it interesting to think about

The manifold really paid off this week. One of the new shut off valves failed and we were able to just isolate that loop from the manifold and not loose the water to the rest of the house![/quote]
The loop System will work fine, the dynamics of it is, as long as the total volume leaving the system does not exceed the flow into the system the pressure in the system will be equal on both sides of the loop.

[phil]

I've got a 3/4" line from the street. I added a tee before the pressure regulator so I have one outside tap at full street pressure. I thought I'd use 3/4 until it gets split to feed the hot water tank , then the rest can probably just be 1/2" pex. I dont; have a lot of long runs just lots of fittings for the bathroom , washer dryer etc. trying to keep everything running or planning for a switchover is a challenge. it never seems to be the right time to shut the water down.

[Gothichome]

Phill, you never miss the convenience of a down stairs toilet till you have to go up stairs for it. Or the other way around. In either direction you change your habits and plan ahead.

[Texas_Ranger]

I'm pretty annoyed with PEX at the moment but that's due to... how shall I say... economic reasons maybe. The gist is that PEX is extremely uncommon in Europe and if you're in one of the rare places that use it you'll have a really hard time finding fittings for any alterations. All I've been able to find on the web is from the US and doesn't fit my metric pipe. The style of fittings used with the few PEX installs I've seen here also requires expensive tools that expand the pipe. You push the fitting into the stretched pipe end and the pipe contracts back to its original diametre, squeezing down on the fitting. I did find some expensive compression fittings from Switzerland but they're like $30 (US) each and plumbing regs. require non-permanent connections to remain accessible so I can't really hide them above a ceiling.

The UK ring final circuit is probably one of the strangest inventions of electrical history. The reasoning was that a) the ring topology slightly reduces wire resistance (and cuts down on losses) and - more importantly - allows you to run smaller size wires while still getting lots of power. They run 32 amps through wire slightly larger than #14 in the US! The two severe downsides are that each break in the ring is a severe fire risk and appliance cords are much too small to be protected by a 32 amp breaker so every plug needs a built-in fuse. I've heard rumours that the ring mains is due to go in the next edition of the wiring regulations but so far nothing from any reputable sources.

[phil]

the ring circuit sounds similar to the water loop I described. It saves wire and also they use 220 not 110 so that saves wire too. I wonder how many pounds of copper they save in an average house. we were trying to fix some plumbing my dad did. I think he reused some old copper pipe that was 10 mm , we baffled over how to join it because it had frozen and broken. eventually a piece of rubber hose and a couple hose clamps got us running. Not too professional but worked for now. I have never seen that size of copper before or since.

my sister had a house here, the company that was making the copper pipe at the time "cheaped out" and made it thinner than spec. the factory saved copper until it was eventually discovered that it was rotting out. then we had all these houses where all the copper needed to be replaced. hers was one of them.

I cut out a small piece in my house. the copper is pretty old and black. I couldn't believe it but I took that piece of pipe and rolled it up in my bare hands , it was so thin that not much left of it at all. that old pipe is likely more pure and softer too I guess. I really should replace some of it. I sort of roughed in some of the pex but was a bit confused about how to approach it. I think a manifold might work best as then I could replace one run at a time from the manifold once I can make that live. I recently reduced my line pressure , thinking that might push the inevitable failure of my old water tank and old copper a little further in the future.

some of my plumbing is run under the joist in the basement I'm trying to get it up in the joist so I can put drywall. its low already so I dont want a spacer. means drilling a few holes. I sort of cringe doing that but I guess it is necessary. i can try to use some of the old K and T wiring holes and just enlarge them a little. I don't suppose it weakens the framing too much.

I guess using NA parts in europe might not fit their codes so you really have to stick with the way they do it. I think they still do commercial buildings in copper, Its better in some ways but the pex goes faster, no soldering, less fire risk. its so common here that any plumber would use it. up til now I always used lead solder, now its a big no no I guess. You are supposed to use that no lead stuff. I never liked it especially for repairs on old pipe.

my house used to drain pretty well if I opened the basement taps. I dont know if the pex really breaks from freezing , I assume it can. its so bendy that it would be difficult to create a system that sloped right so it could be drained out properly like you can with copper. then I guess you need to use air to blow it out. Its nice if you can drain it . for example in a power outage in the cold it might be best to drain rather than freeze up. at our summer place this is a challenge. every year we drain it and blow it out and put antifreeze in the drains, every summer it needs some repair because we failed in some way. Its a big and fairly complex system because it used to be a campground and marina. we have three circuits and a well.

[Texas_Ranger]

Ring circuits don't really save wire under real-life conditions, or rarely. One 32 amp ring uses slightly more wire than two 16 amp radials but provides exactly the same power. The ring's theoretical strength comes in when you want to plug several loads around the 10-amp mark into one circuit. Two 16-amp radials will take two of them, while a ring takes three. That's not a very common situation though. Almost all power-hungry appliances are confined to the kitchen these days (in the UK they commonly put the washing machine into the kitchen as well) but Ireland banned rings in kitchens more than a decade ago because they were prone to overloading.

Watch a few UK electrical videos on Youtube and you'll be amazed how often rings are broken, creating a plain fire hazard! Most European countries also have a slightly different attitude to wiring than the US, requiring extensive testing of new (and in theory existing) wiring. Basic tests are insulation resistance (measuring resistance between the individual wires using 500 V DC), earth continuity, loop impedance (that's a pretty complicated test, essentially telling you how much current will flow in case of a short-circuit as that's limited by the wire resistance both on the supply side and inside your house) and RCD (GFI) trip time and trip current. That's documented and the results handed over to the building owner. Ring circuits add a set of annoying ring continuity tests to that list. Reduced-size earth wires make the plausibility check even more annoying.

Re: PEX: even if US parts were acceptable, they simply wouldn't fit because the pipe diametres don't match! Everything's metric here, except for galvanised and black pipe. Even these are incompatible with US parts because Europe uses Whitworth (British Standard) threads instead of NPT.

[Lily left the valley]

my house used to drain pretty well if I opened the basement taps. I dont know if the pex really breaks from freezing , I assume it can. its so bendy that it would be difficult to create a system that sloped right so it could be drained out properly like you can with copper. then I guess you need to use air to blow it out. Its nice if you can drain it . for example in a power outage in the cold it might be best to drain rather than freeze up. at our summer place this is a challenge. every year we drain it and blow it out and put antifreeze in the drains, every summer it needs some repair because we failed in some way. Its a big and fairly complex system because it used to be a campground and marina. we have three circuits and a well.

Matt Risinger did a few freeze tests on YouTube to compare what happens with various piping types and fittings. There are other vids out there doing similar things, but so far his are the most comprehensive I've seen.

There's two in his Plumbing playlist.

[Texas_Ranger]

We once had the water meter freeze in a really harsh winter. It's in a pit in the floor of an unheated outbuilding and several weeks of -20 C weather destroyed it. After that experience we've insulated the cover of the pit every winter and installed a small electric heater to keep it frostproof. The HDPE pipe on either side of the meter was unharmed.

The bad part of the experience was that our heating system is truly bonkers and runs off the hot water cylinder using a heat exchanger to keep the central heating bit separated from the DHW. By the time we'd realised the pipes were frozen the hot water cylinder had lost pressure and the heating no longer worked. It wasn't as bad as the night we got home to the pilot light of the hot water cylinder gone out and the house at 2 C! I think that was the only night I've ever slept with a pillow over most of my face!