Aqualisa Shower Cartridge Replacement

[Eddie Twadds]

Now I know there is no such things as a stupid question, but....

I need to change one of these:

I assume that I will have to drain the hot and isolate cold water rather than rely on the gubbins within the shower casing?

Just trying to avoid emptying 250 litres of hot water down the drain if I can as there is no HW isolation.

Thanks

[x404]

We used to have one of these showers (Aqualisa thermostatic power shower with the large control on the front?), and I'm sure when I replaced the cartridge I had to isolate the water supply - we had isolators on both hw and cold in a cupboard behind so I isloated it anyway. I can't remember if there are any other valves inside the casing, but I'd expect once the cartridge is removed you'd have water pouring out (unless of course someone has more up-to-date knowledge).

[JoshSm]

Depends on how your system is plumbed but on mine (which has all sorts of shutoffs) just turning off the feed into the hot system is enough to avoid draining it down when fiddling with a tap or whatever.

A bit of water will drain initially then it stops. The rest can't easily drain without either air or water getting in to replace it. Hot store normally fills at the bottom and empties at the top so...

I'll usually just turn off the inlet valve then open some lower taps to let the pipework drain.

If you don't have an isolator at the hot inlet it's fairly easy to add one as you don't need to drain much out once the cold supply is off.

[harryt]

My Aqualisa shower is pumped so I just turned the pump outlet valves off to isolate the supply and flipped the pump power switch to off.
There are several different types of Aqualisa shower cartridges (possibly white, purple and yellow).
Make sure you fit the same colour type.
It's not a difficult job.

[g7jtk]

If there are no isolation valves or valves that work from your storage tank then sharpen pieces of wood to block the outlets from the tank / tanks to stop the flow of water. Replace the shower cartridge and remove the wood. I have even used a carrot for this purpose in the past.

[Eddie Twadds]

Thanks all.

I just shut off cold supply as I have an unvented tank so once the pressure drops the hot water does too.

Slight complication is that one of the screw heads completely crumbled due to rust so I am going to have get creative with the Dremel and power tools.