Shower Problems PLEASE PLEASE Help

[ady4689]

Hi guys.

Need some advice. Our Mira shower keeps going cold. It'll be hot for 20 seconds then cold for 20 no matter how long your in there for. The combi boiler doesnt fire up straight away when you turn the shower on and doesnt stay on either when your in the shower, its fires for a few seconds then just turns off which is when the shower goes freezing cold and then fires up again. It used to be fine, you could be in the shower for 20 mins and have constant hot water, but not any more also the flow doesnt seem to be a great as it used to be but dont know if this is connected. Any help would be great, as we have had engineers out but they cant fix it??

 

[Burnerman]

Showers usually have filters fitted to the incoming hot and cold water supplies...it could be a good idea to check these first!
John

 

[picasso]

Do the taps run hot and cold as well or just the shower?

 

[ady4689]

I've taken the mira mixer off away from the pipes and cleaned out the filters and found nothing there. Also the taps around the house are fine hot water flows well and boiler kicks in straight away and stays on too, thanks for the help guys

 

[swbjackson]

Could be a problem with the boiler. A split diaphragm in the diverter can cause this sort of problem. Some years ago I spent ages trying to rectify a fault with a new shower when the boiler was faulty. It was exactly the same problem.

 

[ady4689]

Could be a problem with the boiler. A split diaphragm in the diverter can cause this sort of problem. Some years ago I spent ages trying to rectify a fault with a new shower when the boiler was faulty. It was exactly the same problem.

It's a Sabre HE 25 boiler so I'm aware that there are quite problematic. How could you tell if it has spilt would it need taking apart? Would there be evidence of leaking water in the boiler?

 

[NEALDEAN]

What's the hose and head like ?
If the hose inner has partially collapsed this would cause hot and cold running as would the head if the jets are blocked.
Basic stuff but worth a try.

 

[gasbanni]

Sounds like its a thermostatic shower and the cartridge has gone !

So run a hot tap if the water runs hot at a constant temperature boilers ok,
so get a new thermostatic cartridge for your shower.

Post model no of shower.

 

[ady4689]

Thanks, what would a knackered cartridge look like? Would there be build up or broken seals? Something like that?

 

[gasbanni]

The thermostatic action is by governed by a wax capsule in the cartridge
it will come as a machined lump of brass ! usually more expensive than it would seem to be by its looks.

Post the model no and I'll post the part no.

 

[ady4689]

I've got the part number cheers pal in the manual. Would this be something I can replace myself if I ordered it?