Shower options

[pmx_super]

Hi,

I want to improve my shower performance. The setup I currently have means a cold shower every morning.

I live in a 2nd floor flat with a flat above and have a 25gal cold feeder tank situated directly above a 50gal tank in a cupboard. I have a venturi unit fitted which simply does not work satisfactorily due to the -ve head of water.

A quick fix would be to reinstate an electric shower unit that has been wired in in the past. It would give a crap shower but at least it would be hot. I like a powerful shower so I've pretty much rejected this option already.

Having done some research I've arrived at the following 2 options:

1) Pump the gravity fed system
2) install a mains pressure (unvented) hot water tank

I have questions regarding both, which is why I'm here!

On (1) -

I understand I would need a 50gallon cold tank for this to be possible. Is this a must-have or nice-to-have? Is there not some way to improve the re-fill rate of my 25gallon tank to avoid the risk of the tank emptying?

If I MUST have a 50gal tank - do they come in different shapes? All I've found is one approx 600x600x1200 which wouldn't fit in the cupboard as it is.

On (2) -

The Redring LWSS150D looks suitable - but it says it needs a minimum 1.5bar and 25l/min at the mains input. How can I get some indication as to whether I have sufficient pressure & flow without ripping out the tank to access the mains feed? (Measured at the kitchen tap the flow is about 12l/min.. though I suspect this would be greater at the main feed to the flat).

They claim pressure at the hot outlet equal to mains - is this true? I have a pressurised undersink water heater in the kitchen and the flow out of that is way less than the cold.

If I lose my cold tank the toilets and all of the cold taps that fed from it will have to be plumbed into spurs off the mains right? Is this feasible? Are toilet cisterns and bathroom taps ok operating at mains pressure?

Apologies for the giant post - any answers to any questions appreciated.

James

 

[GJS]

I know nothing about mains pressure HW systems but you don't HAVE to have a 50 gal cold tank.

What is the 50 gal tank you mention, under the cold tank? Is that the hot?

At my old house I had a 25 gal cold tank. I fitted a 2 bar salamander pump. I did put a pressure restrictor in the mixer valve because I was concerned about the cold tank running dry, but it was still a very decent shower.

In my new house I have a 50 gal tank and have fitted the same pump, no restrictor and a high flow shower head - in other words gushing. It takes 10 mins for the tank to go down by a quarter to a third. So it would run for at least 30mins. In theory then, yours would run for at least 15mins with a very good flow rate.

If the tank runs dry the pump will switch off but it might destroy itself if it sucks in too much air. So worst case it that you would be £200 out of pocket plus 30 minutes to fit a replacement.

If I was in your position having a cold, crap shower every morning, all you would hear by now is car tyres screeching at the end of the road as I head off to the pump shop!

Just one other thing if you go down the mains HW route, you will get the same pressure at the outlet as the inlet, but flow rate is just as, if not more, important than pressure. One needle like jet of water coming out of your shower head at 10 bar does not make a good shower. If someone chucked a dustbin full of water over you, that would be an excellent shower (if a little short lived) at practically zero bar, but at about 30 gals a second!

 

[pmx_super]

I'm now swinging back towards the pump option - though it's far from a case of simply 'slapping on a pump'. The pipework to the shower unit is all hidden behind the 50 gallon hot water cylinder in a walled-in cupboard. There is literally zero access, so the hot water cylinder would have to come out first.

Whilst digging around the internet for bigger tanks I found these two things which come as a single unit with a 50 gallon cold feed over a slightly smaller hot cylinder:

http://www.mcdonald-engineers.com/products/timesaver.htm
http://www.lycrisbyrne.com/combo1.html

I think they would both fit in the cupboard - just need to find one for sale in England now!