hot water cylinder may be too small :(.... advice needed pl

[pappasmurf]

the other day visited the Hans-Grohe showroom in Esher/surrey and was very impressed with their selection of bathroom shower heads and other bathroom fittings. choose a very expensive shower head (£500 approx.) but was disheartened with the fact that the flow rate of this shower head was 20lt/min. which means if i have a 300lt megaflow tank then this tank would probably empty of hot water in approx 15mins!.... and i have 4 bathrooms to feed!.... i was thinking of going for a conventional megaflow system because this i heard was the best system for the number of bathrroms i need to feed. but i didnt invisage this sort of flow rate (20lt!) from each shower head!....can someone pls suggest an alternate system that i should have installed that would satisfy my requirement.

 

[sloppytom]

You can fit flow restrictors in the shower outlet

 

[ALEC1]

well a decent coil in the cylinder and a priority reheat will top up the hot water as soon as the cylinder sees a deterioration in the temperature...


whether the megaflow has a decent size coil is anyones guess!

 

[Corgigrouch]

Your calculations are erroneous.. What's your budget? Have you got enough water flow and pressure coming into the building?

 

[Space cat]

the flow rate of this shower head was 20lt/min. which means if i have a 300lt megaflow tank then this tank would probably empty of hot water in approx 15mins!....

I wouldn't like to take a shower in water straight from the hot tank at, what, 60°C! Almost half of that 20 l/min will, hopefully, be coming through the cold inlet so your tankful will last longer than you think.

And Corgigrouch is correct; you haven't really thought this through. Are you assuming that all four showers will be running at once and, if so, is your incoming water supply up to it? Do you really need that kind of flow rate anyway? Can you educate people to turn a shower off when they're not actually standing under it? (Sadly, this concept will be lost on many women and almost all teenagers. )

 

[pappasmurf]

reply (sloppytom) don't really wonna fit flow ristrictors as this would mean i might as well go for a less powerful shower head, which i really dont wonna do!

reply (Alec1) the megaflow will be a Heatre Sadia; so i'm in their hands as to what coil is used in their tanks!.... the boiler will be a Worcester Bosch Heat only or system boiler.

reply (Corgigrouch) i have just had an upgraded water supply installed by Thames Water from the street to the main stop valve in the house. this size is a wapping 32mm blue pipe (not 28mm!)and the flow and pressure is just brilliant.
don't really have a budget at the moment as i don't know what other system apart from a megaflow system is out there that can provide these sorts of expectations.

reply (space cat) i have to assume the worse and yes the showers can and probably will be used "all" at once. the info on water supply is above. and yes u are right u cant educate people all of the time! and even i am a culprit of this.

hope these replies to all your question will help you guys in helping me sort this dilema out.
spoke to the Hansgrohe chap and he just said that i should contact the heating design engineer for this solution. but all the experience i have had in the past with plumbers is that their ok for any mainstream bog standard installations and anything slightly complicated they tend to shake their heads and just disappear!...... pls someone help

 

[Dan Robinson]

With this attitude and method of planning you are into an expensive world of hurt my friend.

Now, completely REVERSE everything you have done and start from there.

 

[pappasmurf]

hows that

 

[Dan Robinson]

Been there, seen it, had to re-work enough fookups that started exactly this way.

oooh look, that shower looks pretty"

Trust me and read the advise given so far.

Your new water main is not "wapping". A Megaflo is made by Heatre and is not all that.

Without figures, your pressure and flow is not "brilliant", it is what you have.

Hans Grohe want to sell you a fancy over rated and over priced shower.

Who chose a Worcester boiler and why? ( I am WB accredited so won't disagree on general principal).

 

[pappasmurf]

ok then dan robinson tell me what to go for?..... this is why i am here!.... currently the property is let out but eventually it will be an 8 bedroom 4 bathrooms 2 kitchens property. with the whole house having underfloor heating. so come on then suggest a system!... show me the way!

 

[Corgigrouch]

Well lets start with what you have.... Incoming flow and pressure? Then we can give you some indication of what you can have fitted and expect it to perform correctly.....

 

[pappasmurf]

i simply cant answer that question as i do not know!..... when the sink tap is turned "on" and on full it really is hard to keep your hands under neath the tap!.... thats all i can say. lets just "assume" it is brilliant! as i would need to get a flow meter etc etc!.

 

[Dan Robinson]

See what I mean?!

"Doctor doctor, it hurts!"

"Where"

"Dunno, I'll need to phone a friend".


What is "brilliant"? I have 6bar water pressure on a 25mm supply and home. What is my flow rate? I know at11l/min my pressure is around 5.75bar.



You HAVE to give us more information than you have. Sorry, but it is the way of things.

 

[Corgigrouch]

Well until you can give us the data that we require then I fail to see how we can present a solution

 

[pappasmurf]

ok fine then!........ i have I have 6bar water pressure on a 32mm supply and i have at 11l/min my pressure is around 5.75bar!.......... now lets go from here!