Gravity Fed Shower pressuers - Manufactuers specs?

[parky]

I am planning on fitting a gravity fed 'deluge shower kit' and see quite different information on manufactures specs.

Currently I have a simple bath mixer tap with shower attachment, and in the long term will be planning on fitting a power shower (have cold and hot water tanks) but as a short term measure was going to replace the shower attachment with a "Deluge shower riser rail kit" - as the current shower attachment doesn't even have a riser rail. These kits seem to have a short length of hose which connects to the existing shower attachment connection on the mixer tap (assume these are all standard 0.5 inch connectors)

The hot water tank is on the same level (first floor flat) and the cold water tank is in the loft, giving approx 2 metres Head.

My problem is the disparity in "minimum working pressures" given by different suppliers for a simple riser rail shower head. and was wondering whether I should heed their advice or ignore it. The current shower attachement gives an OK pressure (as good as I would expect from 2 metres head).

Screwfix offer one type with a switchable separate handset (part 22414) which requires 0.35 Bar - which is 3.5 metres from my maths - not possible for a gravity fed shower only one floor below the tank.

But Screwfix also offer another type without the switchable handset (Part 21824) which claims to work of 0.2Bar (2 metres, so seems more feasible) but cannot see why this would be different - is it base on pressure lost going through the handset switch?

To further complicate things, Argos sell an almost identical unit (part 832/1444) which claims to need 20PSi. Thats 1.37 Bar, or 13.7 metres of head - are they serious?

Does anyone know why this would be? is there any difference between these units in reality? I've added the links below to the three items in case anyone would like to check them out

Screwfix 0.35Bar
http://www.screwfix.com/app/sfd/cat...WYGALRCJO2C3CJ0Q?cId=101204&ts=29431&id=22414

Screwfix 0.2Bar
http://www.screwfix.com/app/sfd/cat...WYGALRCJO2C3CJ0Q?cId=101204&ts=29431&id=21824

Argos
http://www.argos.co.uk/static/Product/partNumber/8321444.htm


Thanks

Dave

 

[ricarbo]

I haven't got an answer , but----- I fitted just the head (pancake) from a unit I bought in Homebase, very similar in appearance to the Argos unit you show. This was in substitution for the slightly smaller original one supplied with a Tre Mercati shower head that didn't have a swivel. the flow rate was so poor that I took it back and that's with about 5 metres head measured from the bottom of the storage tank to the shower head, all supplying pipework in 22mm to the shower mixer and 15 mm thereafter. So, I don't think you have enough information for any confidence. Suggest you ask the manufacturer for full details including flow rates. Just because the pancake is large diameter, it doesn't mean you going to get a lot of water out of it. I shouldn't be surprised if 2 Jags and his pals come up with some rule limiting how much of a decent showr we're allowed.
I don't like them, because they are a complication and can be noisy/maintenance problem, but you could consider a pumped supply to the shower, if you really cant raise up the tank to get a bit more head. Again you will need to research what the manufacturer specifies, before you fit one though, not always as entirely straightforward as you might hope.

 

[chrishutt]

Does anyone know why this would be? is there any difference between these units in reality?

Yes there is a lot of difference in the units. You won't get satisfactory performance with those that require more pressure than you have available. Go with the 2.0 metre one, but don't expect anything much from it, since you'll be right at the bottom end of the operating range.

Why not try a different approach to the whole thing and look at venturi showers. These use your mains cold pressure to boost the tank fed hot pressure, so effectively giving you power shower performance without the bother and noise of pumps. Try Trevi boost and the New team one sold by screwfix.

 

[phlip]

Bought one of these Rail Showers. Have no clue how to fix them!! Anyone know where I can find a manual?[/url]

 

[Jake1886]

Anyone know where I can find a manual?[/url]

Google?

The shop where you bought the shower?