Faulty shower mixer

[Connor Williams]

Hello, I am having problems with a shower mixer, the hot supply is from a megaflow unvented cylinder and the cold is straight from the mains.
The supply is either red hot or stone cold when you use the shower mixer, the mixer is not mixing the water at all, I have examined the cartridge and it doesnt seem to be limescaled up, what could be the problem?
Alas I dont know the make of the shower....

Any help would be greatly appreciated, many thanks.

All the best,
Connor

 

[Plumbstar Tom]

have you checked that the shower is plumbed the correct way round?

Noramlly hot on the left feed

 

[Puddle]

Hello, I am having problems with a shower mixer, the hot supply is from a megaflow unvented cylinder and the cold is straight from the mains.
The supply is either red hot or stone cold when you use the shower mixer, the mixer is not mixing the water at all, I have examined the cartridge and it doesnt seem to be limescaled up, what could be the problem?
Alas I dont know the make of the shower....

Any help would be greatly appreciated, many thanks.

All the best,
Connor

Did it use to work ok,the hot and cold pressures should be balanced to the shower,if not you may find cold is over powering hot,so you have hot and as soon as you turn to cold in stops/restricts hot flow through shower head
You could try turning cold basin tap on slightly and see if it helps,if so you will need a pressure reducing valve on cold to shower,which should have been fitted originaly if you do not have a main balancing valve near cylinder on pressure reducing valve on main coming in

 

[Connor Williams]

Thankyou I will check the cold flow, all the pipework is concealed behind the tiles and I will check with the landlord as to how the shower performed before. The mixer seems okay as I stripped it down and the strainer inside didnt seem to be blocked with limescale, so it must be the hot and cold supply.
Many thanks for the advice.
All the best, Connor

 

[WHPES]

If it's a bar mixer you could reattach it upside down just to test it.