mira 723 mixer shower problem

[wigz]

hi all i have a mira 723 mixer shower, its gravity fed from hot water cylinder. the cold is fed from the cwsc, the cold and hot are connected to the the bath which then tess off in 15 mm to feed the shower. problem is the shower is only luke warm and when turning the mixer valve it dont change the temp at all. if i turn the gate valve off from the cold feed the shower runs hot and also turning the cold on to the bath it runs hot, but soon as i open the tap or gate valve it runs cold. no work has been done since this problem has occured. is it the actual mixer valve thats gone? shower is about 6 years old. thanks for the help.

even turning the gate valve right down to restrict the cold flow dont seem to help either.

 

[Puddle]

sounds like the cartridge requires replacing

Mira 723 | Mira | Shower Spares | Shower Doctor

 

[tamz]

Or depending on your water quality, cleaning it may work. You would know when you looked at it.

 

[wigz]

so best bet is to take it a part, will i have to drain down cylinder?, and the the gate valve dont turn off to well on cold feed so will have to drain tank down too.thanks

 

[WHPES]

What you describe is a common problem with these units and usually down to limescale. Take it apart and you will find what looks like a clock spring. Limescale gets inside the coils and restricts movement. Descale and lubricate with silicone grease. Do not stretch the coil or distort in any way.

Remember to replace the gate valve when you have drained it all down (recommend full bore lever valve as replacement)

 

[kay-jay]

have you checked if there is a non return valve? this could be stuck in the flow position and allowing cold pressure to hold back the hot water. assuming that your cold header tank is higher up than your hot water cylinder

 

[wigz]

thanks whipes will replace with a lever valve.

hi kay jay there is no valves on the sytem, pipes run under the bath then into the wall.

 

[wigz]

i took the shower apart yesterday there weren't a lot of scale in there. so i cleaned it up and applied silicone grease and put it back together following the manuel instructions. when i turned the shower on there was no difference. i did notice one thing though when i turned off the cold feed to the bathroom and opened the cold bath tap i was getting hot from the shower and also was getting hot from the cold tap. so some how the hot is getting into cold threw mixer valve??

 

[kay-jay]

sounds like you may have unbalanced water pressures on the hot and cold.

 

[wigz]

shouldnt be its gravity fed hot and cold,