Shower either boiling or freezing

[atomicnotsoblonde]

Any ideas about what to do? The builder who fitted it has vanished on me.

Both hot and cold water are coming through, just one or the other! They don't seem to be mixing? It's a shower with a bar style control, with temp on one side and flow on the other.

I'm short of funds so need to try to DIY repair if possible? If not, who do I call - a plumber?

Thanks

I think it’s the shower. If it’s new, get it replaced. It should blend the water via the mixer control and it’s not. So it’s faulty. I’m not sure it’s the builders fault. However if he supplied it, he should replace it. I wouldn’t expect this to be rectified by the supplier.

If it's a thermostatic shower he's fitted it upside down.

Or your pipework may be unsuitable. Have you got a hot water cylinder? What colour?

@PigletJohn it's a combi boiler. It's about 7 years old and the other showers work ok.

If it's fitted upside down, is this fixable myself?

Yes, if you can use a spanner and know how to turn off the main stopcock.

Or any competent plumber (a wrinkly, semi-retired one will be fine) recommended by someone you know and whose opinion you trust, will easily do it.

An advert on a website where people pay to be listed, and can remove unflattering reviews, is not a good source

(thermostatic shower mixers are designed to have the hot water pipe connected on the left, and the cold on the right. If they detect the water is too hot, they close the left one a bit and open the right one a bit. If the pipes are the wrong way round, this means that when the water is too hot, they automatically make it hotter. This is a rookie mistake. In some cases there are different adjustments, or you can replumb the pipes, but turning it over is usually easiest, and most people now have a connection plate fixed to the wall, and the shower nuts tighten onto it quite easily)

I can use a spanner! Well I'll have a good try. Is the main stopcock the tap in the house that stops the water? There's one in the house and one on the street.

How do I do it? I'd like to try before having to get someone out if I can.

Try the one in the house. You'll know it works when all taps, hot and cold, stop working.

See if you can find the installation instructions. They may be on the maker's website. Bar showers are fairly common and a different make may be similar.

With luck you will have a screwed plate on the wall

picture of shower wall plate

and the mixer will have two nuts that screw on. If not, and you need a plumber, ask them to supply and fit a plate, it will make future repair and replacement much easier. Bar shower mixers are cheaper than round ones, and IMO do not last as long.

There are different types of plate depending on whether it is surface or tiled over, and if the pipes come down from the ceiling or through the wall. Tell your plumber and provide photos if necessary.

The plumber will laugh if the mixer was fitted upside down.

@PigletJohn this is how it looks

it looks like you have individual wall plates

like these

but square

The shower is not upside down, it might be your pipes are the wrong way round. Feel them where they come out of the wall and see if the left one is hot and the right one is cold.

it might be possible to alter the cartridge in the shower but that will depend on the design

Have you had a shower in that position before? Are the pipes visible anywhere (under the bath, or above the ceiling)?

I can't see any pipes, they are behind tiles. I'll try to check which one is hot and will post again.

@PigletJohn I e checked and yes, the hot and cold pipes are the wrong way around.

plumbing mistake.

if you turn it upside down it will work, but the knob might be dificult to see.

If and when you ever change it, some of the round-bodied mixers from Aqualisa (possibly others) can be fitted the other way round, or you could use a non-thermostatic mixer.

If the pipes are accessible under the bath or in the ceiling, a plumber could cross them over.

Thank you so much. I'm going to try and turn it around if I can. I'm so cross he won't answer the phone! 😤