Shower is either too hot or too cold

[MarkRaf]

Hi

I've recently moved into a new house and inherited a Triton mixer shower (I think it's a Triton Unichrome Aire looking at their website). We have a combi boiler hot water system with reasonable water pressure. Unfortunately the shower is always either too hot (no cold water coming through at all), or it is too cold (very high pressure cold water coming through).

Basically, if you start from the very lowest temp setting, you only get hot water coming through the shower at a normal pressure. As you increase the temperature (past the limiter) then when it reaches approx 45C it suddenly switches to just cold water at high pressure. If you then adjust the temperature setting back down again, at approx 35C the cold appears to cut out again and just leave the hot water again.

When running taps in the same bathroom the water pressure for hot and cold appear to be fairly similar, and I've tried messing around with the boiler temperature to see if that helps, to no avail.

I'm considering the fact the the shower might just be broken and needs replacing - if so is it a safer bet to get a mixer shower or should I go for a thermostatic shower (a little to expensive so would rather keep it cheap if poss!!) However don't want to go to the hassle and expense of changing the shower if the problem is more to do with the water system / pressure etc.

I'm quite happy to refit a new shower as can do v basic plumbing, but have to be honest in saying that I really don't have a clue when things stop working. If checked out the manufacturers website and had a quick look through previous posts, but nothing quite seems to answer my questions.

Any help would be most appreciated before I go wasting a load of money!

Thanks

Mark.

 

[TicklyT]

If you select cold, and get hot water out, and vice versa, I wonder if the supply connections could be reversed?

Turned to 'cold', the thermostat would sense the hot water and compensate by opening the 'cold' inlet (connected to the hot supply), so it gets hotter, so it opens the 'cold' inlet further.

When you select 'hot' it opens the 'hot' inlet (connected to the cold supply). The water cools, so it opens the 'hot' inlet further

 

[MarkRaf]

That would make sense - I'll have a look and see if I can work it out by feeling which pipe gets hot when running hot shower. From looking at some previous topics it looks as if the hot inlet should be on the left hand side as I see it when facing the shower.

If it is back to front I take it there is no problem with fitting it upsidedown??

 

[Technotim]

I would find somwhere to cross the pipes over either in the loft or under the floor it will work upside down if that is the problem.

look a bit strange with the hose coming out the top though...