Anyone had problems with a Mira Sport shower ?

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Evans Electric

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Customer says the shower keeps going hot and cold & scalding .    

I tried it for 15 minutes , it seemed fine  .      I'm thinking its the water pressure  fluctuating  as he says  they use it early doors ,  rest of the street  getting up & ready for work .

Its a Mira Sport Max   /  10.8 KW  . 

Theres the usual heating cylinder inside and a quality looking solid state circuit board  controlling it all . 

 
How old??

Did you supply & fit it?..

Are you liable for repair costs?

If not your product then don't waste time trying to figure out exactly what the cause is...

Just get a new one to fit.

:Salute

 
The "quality looking control circuit board" is just an expensive and more to go wrong gizmo to light some fancy lights and make it work from posh looking buttons. Give me a basic Triton any day for reliability.

The heating element in these is always on at a constant power, and it is water flow rate that adjusts the temperature.  Some have a crude flow regulator but that is about all. If the pressure drops (someone runs another tap or flushes the loo) then the flow reduces and temperature rises.

I have yet to find an electric shower the actually modulates the power to maintain a constant temperature, I don't think one exists?

 
It sounds like there is an auto resetting overheat cut out and the element is overheating the water which then takes out the cut out and the shower goes cold, which allows the cut out to reset and then provide hot water until it becomes scalding.

But this is supposition because it should have shown up in your 15 minute testing.

Possibly it is just scale build up on the element that is preventing the heat getting out until it cracks away and gives scalding water.

They should not be using a 10.8kW shower because they are ridiculous and very easy to overheat the water on loss of flow.

Perhaps it needs a flow booster pump the ensure continuous flow, but I would just replace the shower as the easiest option.

 
How old??                                             Dunno  about 8 yrs 

Did you supply & fit it?..                    No

Are you liable for repair costs?          No

If not your product then don't waste time trying to figure out exactly what the cause is...     

Just get a new one to fit.         They're in the £200   bracket I think 

any smell of burning? Classic for what you describe is other people in the house flushing toilets etc etc
:Salute    Thats what I thought    ....nothing wrong with it when I was there.


Give me a basic Triton any day for reliability.
I agree 

Possibly it is just scale build up on the element that is preventing the heat getting out until it cracks away and gives scalding water.

They should not be using a 10.8kW shower because they are ridiculous and very easy to overheat the water on loss of flow.
We don't get scale in this area TBH  ,   Birmingham  steals its water from the Welsh Valleys .  

Theres a good flow of water from the head  and the 6.0mm feeding it doesn't get hot at all .  

 
Mira state the following:

Shower cycles from hot to cold. 
Showerhead blocked: Remove and descale showerhead.
Hose kinked or blocked:  Check hose and replace if necessary
Water pressure below minimum required for shower operation: Make sure incoming mains water stopcock and/or shower isolating valve is fully turned on. Min 1.0 bar. 
Temperature control or power control setting too high: Turn the power control to Eco or turn the temperature control until a cooler temperature is achieved.

 

You have eliminated the first three so perhaps they just want too hot a shower! (slightly surprising since a 10.8kW shower might be expected to be wanted in order to get a very hot shower)

 
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The shower head nozzles are a weak point on any electric shower, especially if you live in a hard water area. One of the shower manufactures instructions says the head should be removed and cleaned regularly and possibly weekly where high limescale issues are a problem.  But I have never found anyone who every cleans their head at all.

Doc H.

 
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