Axor Independent Shower Unit

[pdfctu]

Hi there hope someone can help me. I am replacing an old aqualisa shower unit, with a new Axor Uno unit. The old one was gravity fed, and the new one is in exactly the same position, although there are now several extra elbows and fittings. The pressure on the old one was fine, but having fitted the Axor, the pressure is pretty dire. The cold and hot feeds are both in 22mm, and the exit to shower flexi is in 15mm. Is it the elbows that are reducing the pressure, or should i run the exit pipe in 22mm and then reduce to 15 just before the flexi.

Hope this makes sense to someone, any help much appreciated.

 

[bathjobby]

but having fitted the Axor, the pressure is pretty dire

Have you a similar shower head fitted or a larger one than before ? Is it the pressure that is dire, or the flow i.e. if you have a much larger shower head you may be getting the same flow but it may not be sufficient for the head. If you have approx 1 mtr of head you can expect approx 6 ltrs per min, have you measured it ?

 

[ChrisR]

I've got an Axor mixer & I'm pretty sure they are or high pressure systems only. Poke about the Hansgrohe site.

 

[pdfctu]

the flow from the feed pipes without the shower unit connected is fine (not measured but def more than 6ltrs per min) It is bad when it exits from the unit. I have temporarily used the old shower head, and get this poor result. The head (tank to shower head) has not changed

 

[pdfctu]

thanks for info - will check the site. I didnt know you had to have a different type of shower unit for gravity fed. Reckon ive made boob.

 

[ChrisR]

Not your fault the website is a triumph of style over substance. It doesn't give any figures. But I know the Axor Stark mixer I have has waterways measurable in millimetres diameter. I doubt you'll be able to take it back.

Had you thought about a pump - yet? (Mine's 4 bar)

 

[pdfctu]

waterways in this unit seem about 15mm. Is that no good for gravity fed?
re pump, have thought about it but cold feed comes from roof and hot feed comes from under floor, so the too runs never get near each other to put both through a pump. Would i have to re run pipes or have a pump on hot and another on cold? thanks for all your help. have emailed axor to ask re gravity fed, it is def nothing to do with fittinhgs and exit pipe diameter then?

 

[Jasonb]

As ChrisR says most of the Hansgrohe stuff is highpressure does it say anything in the instructions?

Jason

 

[pdfctu]

instruction are really basic - just a picture of how the unit fits together. Absolutely no mention of whether only work on high pressures

 

[pdfctu]

Hello ChrisR - have spoken to Hansgrohe, they say that a 3bar pump is needed for adequate pressure. The problem I have is how to put one in. The bathroom has now all been re done, and I dont really want to rip it all out again. The section is ready for the shower valve, the cold feed is in 22mm and comes down through the stud wall from the loft tank (independant feed). the hot (22mm) comes under the floor from the cylinder 2 rooms away and up through the same stud wall. So the two feed pipes do not at any point run parallell. Any advice as to fitting a pump to this set up? Can you fit one in the stud wall?? or do you have one on each feed ?? Really confused as to wot to do..... and help/advice would be greatly appreciated ..... thanks again thus far.

 

[Jasonb]

You could use two single booster pumps but I have only seen them at 1.5bar but bigger ones may be available.

Are your tank & cylinder big enough to supply the additional volume of water.

Jason

 

[pdfctu]

there was an old shower there before (gravity fed) , so i am only assuming that tanks can handle the volume. The cold is supplied by its own seperate cold tank, not sure if hot cylinder is big enough. Do you mean if pumps are fitted the tanks cannot supply enough water quick enough for pumps to work properly??

 

[ChrisR]

[code:1]Do you mean if pumps are fitted the tanks cannot supply enough water quick enough for pumps to work properly??[/code:1]Not exactly. There are 2 issues:
1) you need the pipes to come from the right places to the pumps. CW one comes from the big tank, detail of the HW connection depends on the pump size, but it has to go back to the HW cylinder.

2) If you punp a shower it might take you from 5 litres/min to 15 l/min. So you don't get many showers from a (say) 120litre HW cylinder.

 

[pdfctu]

detail of the HW connection depends on the pump size, but it has to go back to the HW cylinder.

sorry but a bit confused, I understand that cold feed comes from loft tank (that is the case) Can i therefore put a pump on this feed?. Hot feed comes from the cylinder, can i put a pump on this feed (dont get that it has to go back to the cylinder? .... lets assume for a mo that the cylinder is large enough.

There is about a 2m head which i think is about 0.2 bar ... do you think it is simply better to try to change axor valve for a low pressure one, or do you think the head is not sufficient for this? thanks for all your help so far

 

[pdfctu]

sorry dont know what happened with my text then

MOD

press the edit button and put it in