Aqualisa - shower threads in the UK

[johnuk]

I bought a filter for my shower online, the manufacturer says it's 1/2" female/male, inlet/outlet. Turned up, tried fitting it, no go. The fixed (plastic) Aqualisa arm on the wall is too small for the 1/2" female inlet and vice versa for the shower head it's self, the 1/2" male on the filter is visibly too big for the shower head. I tried measuring the arm and shower head as accurately as I could. It seemed they could be 3/8" BSP. I order some reducers up quick with the Easter weekend coming up. They arrived this morning, was looking forward to finally getting the thing on there. No luck! The 3/8" BSP doesn't fit either. The male is doesn't even engage with the threads on the shower head its so loose and the female won't even start on the arm. The 1/2" on the reducers does fit the filter though. So the shower arm and head are neither 3/8" BSP or 1/2" BSP.

I've been searching all over for some explanation or reference on the threads, then I found this on showerdoc:

Can you please tell me the thread size of the male thread on the end of the arm. If it is not 1/2" BSP do you have a part number for the equivalent 1/2" BSP arm? Alternativley do you sell a thred reducer that will allow a 1/2" BSP shower head to fit the 18mm thread of the older style Aqualisa arm?

The thread on the end of the arm is 1/2" BSP

UPDATE

Since this reply was first posted there have been various discussion about the thread size and to be honest we haven’t been able to establish which is correct, what follows may help! There two different arms and they both look the same one is chrome brass and the other is chrome plastic there also two different heads which look the same one will only fit the plastic arm and the other will only fit the brass arm, at the moment the thread sizes appear to be unique to Aqualisa

Seriously!? Custom threads!? :banghead:

 

[Masood]

Seriously!? Custom threads!? :banghead:

One way to make sure of revenue from parts sales...

 

[Radioman]

Known fact with us Aqualisa engineers is don't fit any shower head or hose except genuine a genuine part. Our hoses have larger internal diameter, our shower heads the same

 

[Radioman]

Smaller internals eventually cause a problem with seals and stats

 

[Mike123]

I bought a filter for my shower online, the manufacturer says it's 1/2" female/male, inlet/outlet. Turned up, tried fitting it, no go. The fixed (plastic) Aqualisa arm on the wall is too small for the 1/2" female inlet and vice versa for the shower head it's self, the 1/2" male on the filter is visibly too big for the shower head. I tried measuring the arm and shower head as accurately as I could. It seemed they could be 3/8" BSP. I order some reducers up quick with the Easter weekend coming up. They arrived this morning, was looking forward to finally getting the thing on there. No luck! The 3/8" BSP doesn't fit either. The male is doesn't even engage with the threads on the shower head its so loose and the female won't even start on the arm. The 1/2" on the reducers does fit the filter though. So the shower arm and head are neither 3/8" BSP or 1/2" BSP.


It seems nobody makes a converter from the Aqualisa approx 18mm thread to standard 1/2" thread. I have been able to use a 1/2" shower head on an old Aqualisa system by using an old Axis head which uses a 1/2 thread to go into the shower head itself, female 18mm approx to 1/2". It is too long as is as it's a custom fitting but using a hacksaw to level off works. You end up with a converter that works well. Of course you do need the old head in the first place!