Polarity of water feed to thermostatic shower

[Roland Perry]

My wall-concealed thermostatic shower mixer valve (hansgrohe) has seized up and only emits cold water. Looking at the price of the closest contemporary equivalent I can find (>£300) I'm not confident I can get an affordable spare. And it needs fixing before Xmas.

So I'll probably replace it with a new and cheap surface fitted one (it's 12 years old). But I don't know which side is hot feed and which cold.

And I can't run it to find out, because only cold water comes out :(

Is there a convention for this (eg hot on the left and cold on the right?) and do most manufacturers follow it. Transposing them would be a PITA given the way the feed pipes are cemented into the wall.

I could undo some of the connections and see what happens, but that'll be a bit messy, so if there's a "standard" that would help a lot.

[Andy Burns]

Can't speak for Hansgrohe, but Mira allow you to reverse the thermostatic module, so either is possible.

[docholliday93]

There is a standard for sinks and so on which says you should have hot on t= he left - I don't know whether shower makers follow this, though it would m= ake some sense in avoiding crossover of the pipes, assuming the plumber has= followed the standard - the way they haven't in virtually every house I've= owned...

Though you should watch out, as what the manufacturers say you can do isn't= always possible - my mother's shower was fitted according to the manufactu= rer's instructions, but was impossible to control, as you'd expect if it we= re fitted with the hot and cold the wrong way round. I thought from the inf= o on the manufacturers website that it would be easy to change the thermost= atic capsule - they even gave full directions for doing so. Unfortunately w= hen we looked at the thing itself there was an extra lug not shown on the d= rawing, which prevented the capsule being moved. (we got round this by turn= ing the whole unit upside down, in the end).

[Grimly Curmudgeon]

left - I don't know whether shower makers follow this, though it would make some sense in avoiding crossover of the pipes, assuming the plumber has followed the standard - the way they haven't in virtually every house I've owned...

It's a standard universally ignored by nearly every wrong-headed, muddled f****it that's plumbed nearly every house I've ever been in. It makes sense to stick to it - hot on the left - but for some strange reason, some peoples' brains don't work that way. I think they're mainly arts graduates, wrongly sent to the post-grad plumbing courses.

[Roland Perry]

In message , at

08:05:34 on Fri, 7 Dec 2012, [e-mail] remarked:

left - I don't know whether shower makers follow this, though it

has followed the standard - the way they haven't in virtually

The rest of the house is "hot on the left" (although this is the only such shower), so I'm keeping my finger crossed.

[Davey]

It sounds as though most installations are the reverse of the theoretical standard, so accepting that hot is on the right will produce fewer surprises. Simples.

[Roger Mills]

Do you not have isolators on the hot and cold feeds? If so, turn them off in turn and see what happens. The one which stops *all* flow must be the cold.

I've just had a look at the photos which I took when I installed a bar mixer a couple of years ago, and the hot is definitely on the left and cold on the right. They must surely(?) all be the same, to make them interchangeable.

[Gordon Henderson]

Warm both pipes (blowtorch, hair drier, etc.)

Run the shower.

One pipe will get colder quicker.

Gordon

[Roland Perry]

In message , at 18:07:47 on Fri, 7 Dec

2012, Roger Mills remarked:

There's one stopcock next to the pressurised hot water tank, but that turns off both the cold and hot flow to the whole house (apart from the cold supply to the kitchen sink).

Although all the basins, toilets and the bath have separate local isolators, this shower seems the odd one out in not having any.

But with no flow at all to the hot, that would not get me any closer to finding which of the two feed pipes is the hot. What I'd need is hot water to flow, and heat up the pipe. I don't want to disconnect the shower the "feed" side of the apparatus, because that would mean the water would get everywhere, including down the cavity wall.

[Roland Perry]

In message , at 18:22:49 on Fri, 7 Dec 2012, Gordon Henderson remarked:

That's a good idea, thanks.

[Grimly Curmudgeon]

But it's not that simple, is it? Actually, the majority of houses I've been in, have hot on the left, but even in the same house I've found hot on the right, as a bonus surprise. It's still a significant figure, anway. No, if it actually is a standard, and not just use and custom, it should be enforced if at all possible (some hope of that), as grabbing a handful of what you think is cold water, only to have your palm scalded might not be a barrelful of fun.

From what I can see, I believe that if someone is brought up with the taps 'the wrong way round' that's what they'll do in any house they plumb themselves or tell their plumber to do for them. They just don't know or don't care, or are too wilfully stupid to learn the correct way.

[Apellation Controlee]

left - I don't know whether shower makers follow this, though it would make some sense in avoiding crossover of the pipes, assuming the plumber has followed the standard - the way they haven't in virtually every house I've owned...

Not just me who insists on this then. :-)

[Roland Perry]

In message , at 06:58:22 on Sat, 8 Dec 2012, Grimly Curmudgeon remarked:

My house was built in 2000, and everything in it seems very consistent.

All the way down to the plumber they used, who consistently didn't do his joints very well (either in the supply piping or the wastes).

Another reason I'm replacing the whole unit (rather than just fixing the broken thermostat) is that there's a leak between the on/off tap and the pipe to the hose outlet (on which the flexible hose attaches). All buried behind the tiling and behind what was mortar, before the years of water leakage leeched out everything except the sand.

[A.Lee]

You only need a new thermostatic cartridge fitting. It's a 15 minute job normally. Costs anything from £30 to £130.

are the most helpful supplier for these things, and may have a diagram on their site, but they are not the cheapest. If you haev a model name/number, then it is easy to identify the part.

I've looked, and this gives you an idea:

Alan.

[meow2222]

Run the shower and the cold feed will get colder. Simples.

NT

[Roland Perry]

In message , at 10:57:28 on Sat, 8 Dec 2012, A.Lee remarked:

The cartridge there is £132, and I've bought a whole new shower fitting for that. Although mine's not a bar unit like that, it's a recessed one with no part number visible.

[<me9]

Custom used to be using the shorter run of pipe for the hot supply. Fuel efficiency and obtaining the supply quicker.

Most taps have an indication as to which supply they are on, although some modern ones become undecypherable within a short space of time.

[Apellation Controlee]

------------8><

I thought it was evolution, from when most houses had running cold water, but not hot. The single tap would therefore have been on the right (max convenience for most people) so that, when a hot supply was later added, it was positioned in the remaining vacant position.

[YAPH]

That's it: hot on the left, cold right, on all the showers I've come across. (Same as taps are supposed to be, as others have remarked)

[Andrew Gabriel]

Cold tap is on the right because most people are right handed and old taps could be very stiff (even when new). Hot taps didn't start appearing until about 50 years later.