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mutley racers

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of water through pipes at different pressures and sizes?
 
This is what I am upto. Calculating the flow to 2 showers and a bath running simultaneously.

I installed a 25 mdpe into my house which comes off at 22. The flow rate before at my outside tap was 20 litres a minute and went down to 10 with another tap on. Now with the new pipe it overflows the weir gauge (although when testing with a bucket it was 20 litres a minute) and I get 18lpm with another tap on. With the bath on I go down to 14lpm so 3 taps.

When checking flow rates though, it is only coming through a 15mm pipe to the tap and the maximum flow through this pipe is 22lpm at 3 bar. So, this test really is not that accurate.

Long winded I know. I just want to see if I should put an accumulator in really.
 
Depends are you going to be running all 2-3 at once ?
 
As in shower heads? Looking at a 3 way cross water shower valve. Not sure what shower heads yet as I want recessed in ceiling but theirs are like 1k each.

Probably looking at 18lpm each head with the bath running at same so looking at 54lpm and then the dishwasher and washing machine etc so it looks like I will be needing one.
 
As in shower heads? Looking at a 3 way cross water shower valve. Not sure what shower heads yet as I want recessed in ceiling but theirs are like 1k each.

Probably looking at 18lpm each head with the bath running at same so looking at 54lpm and then the dishwasher and washing machine etc so it looks like I will be needing one.

Yep also 28mm main to there from the stop tap
 
And I thought we were meant to be saving water :rolleyes:

In reality are you going to be running two shower heads in the same shower at once? I have two, and I never have them both running at the same time (Although I can). Also, bigger the shower head the more you feel like you're drowning in the shower. Made the mistake of having a 300mm square soaker at first, but you felt like you were drowning when you were under it at 20lpm. So changed it for a 200mm round and it's much much better.

Also you're saying you'll be running all these at once, but you're going to need one big cylinder of HW to supply all these at 54lpm.

So shower at 38oc, at 18lpm will use (Stored HW at 60oc and incoming 15oc) 9.2lpm HW. * 10mins that's 90L of HW. Mutliply that by your two shower heads, that's 180l of Stored HW you require for just one shower. Add in another bath being drawn off and other things you'll be wanting 400l+ cylinder at least IMO.
 
And I thought we were meant to be saving water :rolleyes:

In reality are you going to be running two shower heads in the same shower at once? I have two, and I never have them both running at the same time (Although I can). Also, bigger the shower head the more you feel like you're drowning in the shower. Made the mistake of having a 300mm square soaker at first, but you felt like you were drowning when you were under it at 20lpm. So changed it for a 200mm round and it's much much better.

Also you're saying you'll be running all these at once, but you're going to need one big cylinder of HW to supply all these at 54lpm.

So shower at 38oc, at 18lpm will use (Stored HW at 60oc and incoming 15oc) 9.2lpm HW. * 10mins that's 90L of HW. Mutliply that by your two shower heads, that's 180l of Stored HW you require for just one shower. Add in another bath being drawn off and other things you'll be wanting 400l+ cylinder at least IMO.


I like to have showers with the wife you see. Saves us time when getting ready to go out and the kids like playing in the bath with the taps when we do.

Yep, a lot of water. And, these systems will all be going in the loft!!

Thanks for the advice guys
 
And I thought we were meant to be saving water :rolleyes:

In reality are you going to be running two shower heads in the same shower at once? I have two, and I never have them both running at the same time (Although I can). Also, bigger the shower head the more you feel like you're drowning in the shower. Made the mistake of having a 300mm square soaker at first, but you felt like you were drowning when you were under it at 20lpm. So changed it for a 200mm round and it's much much better.

Also you're saying you'll be running all these at once, but you're going to need one big cylinder of HW to supply all these at 54lpm.

So shower at 38oc, at 18lpm will use (Stored HW at 60oc and incoming 15oc) 9.2lpm HW. * 10mins that's 90L of HW. Mutliply that by your two shower heads, that's 180l of Stored HW you require for just one shower. Add in another bath being drawn off and other things you'll be wanting 400l+ cylinder at least IMO.

Thanks for the reply.


Maybe a thermal store would be better?
 
Thanks for the reply.


Maybe a thermal store would be better?

Personally I think no. I'm not a fan of thermal stores, an Unvented cylinder which is large enough is plenty IMO. All I was getting at was really are you going to be using 54lpm in reality. The other way to combat cylinder size if you're struggling for space too is to store the HW at a higher temperature (70oc) then put a mixing valve on the outlet mixing down to 55oc (So it works similar to a thermal store).

I think really you'd get away without an accumulator. Your issue will be you'll always be limited to 3 bar of pressure anyway on the Unvented outlet due to the PRV so as long as you've got the flow through your incoming main and the correct pipe sizing to your showers etc. you should be fine. Are you able to do balanced cold to the house or at least showers and bath from the loft?

OSO used to allow you to up the PRV setting if you increased the expansion and uprated the blow off on the combination valve. However I'm not sure if they still do this (Or any other manufactures) as we stopped fitting OSO.

Final thing too, I'd avoid fitting a cylinder in a loft if possible especially in your own house. When that cylinder goes or something starts leaking it'll be a waterfall through the ceiling. Right above the bedrooms too.
 
Personally I think no. I'm not a fan of thermal stores, an Unvented cylinder which is large enough is plenty IMO. All I was getting at was really are you going to be using 54lpm in reality. The other way to combat cylinder size if you're struggling for space too is to store the HW at a higher temperature (70oc) then put a mixing valve on the outlet mixing down to 55oc (So it works similar to a thermal store).

I think really you'd get away without an accumulator. Your issue will be you'll always be limited to 3 bar of pressure anyway on the Unvented outlet due to the PRV so as long as you've got the flow through your incoming main and the correct pipe sizing to your showers etc. you should be fine. Are you able to do balanced cold to the house or at least showers and bath from the loft?

OSO used to allow you to up the PRV setting if you increased the expansion and uprated the blow off on the combination valve. However I'm not sure if they still do this (Or any other manufactures) as we stopped fitting OSO.

Final thing too, I'd avoid fitting a cylinder in a loft if possible especially in your own house. When that cylinder goes or something starts leaking it'll be a waterfall through the ceiling. Right above the bedrooms too.

Hi

Thanks for the good advice.

I like the idea of upping the temp of the cylinder and blending down.

Yes, easily be able to put the prv on the mains before any outlets for balanced supplies. I will also change all the piping to the correct sizes for each outlet rather than the 15mm it is all over due to a combi being in here.

Only place for the system to go now is in the loft until I turn the garage into a utility room.

As you have decent shower heads, can you recommend any? I am keen to try the water boarding experience and see how it goes!!!
 
And I thought we were meant to be saving water :rolleyes:

In reality are you going to be running two shower heads in the same shower at once? I have two, and I never have them both running at the same time (Although I can). Also, bigger the shower head the more you feel like you're drowning in the shower. Made the mistake of having a 300mm square soaker at first, but you felt like you were drowning when you were under it at 20lpm. So changed it for a 200mm round and it's much much better.

Also you're saying you'll be running all these at once, but you're going to need one big cylinder of HW to supply all these at 54lpm.

So shower at 38oc, at 18lpm will use (Stored HW at 60oc and incoming 15oc) 9.2lpm HW. * 10mins that's 90L of HW. Mutliply that by your two shower heads, that's 180l of Stored HW you require for just one shower. Add in another bath being drawn off and other things you'll be wanting 400l+ cylinder at least IMO.

Hmm. Very 'American'.

I do agree that a 400L cylinder with an anti strat pump and HW set to prioritise but perm on would work. However a much bigger question/concern pops into my head...

I'm sorry but, unfortunately, I cannot but help feel this is an extremely self centred approach to water use. It is in direct opposition to the societal direction of water use in general and takes not one jot of account for the needs of fellow citizens by demonstrating zero consideration for the environmental impact of wasting so much precious potable water.

Just my two penneth.
 
As you have decent shower heads, can you recommend any? I am keen to try the water boarding experience and see how it goes!!!

Roper Rhodes shower heads on Hans Grohe iBoxes. I've got 22mm to the valve, then 22mm to the head too. They don't seem to restrict the flow, where as Hans Grohe seem to limit the flow rates on the shower heads. Heres their technical docs which I found useful -

https://www.roperrhodes.co.uk/wp-content/uploads/2012/07/Fixed-Head-Flow-Rates9.pdf
 
I'm sorry but, unfortunately, I cannot but help feel this is an extremely self centred approach to water use. It is in direct opposition to the societal direction of water use in general and takes not one jot of account for the needs of fellow citizens by demonstrating zero consideration for the environmental impact of wasting so much precious potable water.

Just my two penneth.

Without getting too much off topic....

Whilst yes I agree to a point, you have to take into consideration how much wastage goes on in the network, our local area over 400 million litres a day was lost in network leakage in 2017/2018. Then throw in the fact that many people have dripping taps, overflowing toilets, amongst other things someone trying to get a decent shower at 20lpm is the least of our worries! And if you're on a water meter you're paying for it anyway. TBH I find the people who waste the most water are the ones not on meters.
 
Hmm. Very 'American'.

I do agree that a 400L cylinder with an anti strat pump and HW set to prioritise but perm on would work. However a much bigger question/concern pops into my head...

I'm sorry but, unfortunately, I cannot but help feel this is an extremely self centred approach to water use. It is in direct opposition to the societal direction of water use in general and takes not one jot of account for the needs of fellow citizens by demonstrating zero consideration for the environmental impact of wasting so much precious potable water.

Just my two penneth.

Hi

Thanks for your opinion. I am doing my bit to save water to the population of Surrey and surrounding areas by fixing dripping taps with the tap medic I purchased from you!!
 
Whilst, obviously, your taste in professional products is utterly faultless :D, I'm still genuinely convinced you can achieve as good a result by using less water. ;)

I do know that shower companies are using aerated water to give the feel of more flow for less pressure etc. I have not really dealt with them much.
 
Without getting too much off topic..

Whilst yes I agree to a point, you have to take into consideration how much wastage goes on in the network, our local area over 400 million litres a day was lost in network leakage in 2017/2018. Then throw in the fact that many people have dripping taps, overflowing toilets, amongst other things someone trying to get a decent shower at 20lpm is the least of our worries! And if you're on a water meter you're paying for it anyway. TBH I find the people who waste the most water are the ones not on meters.
Roper Rhodes shower heads on Hans Grohe iBoxes. I've got 22mm to the valve, then 22mm to the head too. They don't seem to restrict the flow, where as Hans Grohe seem to limit the flow rates on the shower heads. Heres their technical docs which I found useful -

https://www.roperrhodes.co.uk/wp-content/uploads/2012/07/Fixed-Head-Flow-Rates9.pdf


Hi, thanks for the links and advice. I shall have a gander now.
 
Whilst, obviously, your taste in professional products is utterly faultless :D, I'm still genuinely convinced you can achieve as good a result by using less water. ;)

What I actually want to achieve is to be able to get out of the house on time in the mornings and evenings. This is not possible without running 2 showers or 1 shower and 1 bath and maybe the occasional 3rd outlet all on at the same time. 3 kids, a wife with a seriously thick, long head of hair to wash and I all being able to bath and shower at the same time would help. So, we will be using the same amount of water but just all at once rather than separately.
 
Ahh. Visions of a hair advert with a luscious mane being tossed around....

Tell you one thing I've found. Things like 300mm heads give less flow than 200mm heads. Also, to be really effective the flow needs to be concentrated. My wife & 15 yr old have long hair so they end up using the more focussed jets on the shower head otherwise it apparently takes bloomin ages to wash all the concoctions out.

By using slightly smaller and/or more focussed heads youll def need less stored water so wont need a plant room :)
 
Ahh. Visions of a hair advert with a luscious mane being tossed around..

Tell you one thing I've found. Things like 300mm heads give less flow than 200mm heads. Also, to be really effective the flow needs to be concentrated. My wife & 15 yr old have long hair so they end up using the more focussed jets on the shower head otherwise it apparently takes bloomin ages to wash all the concoctions out.

By using slightly smaller and/or more focussed heads youll def need less stored water so wont need a plant room :)

All these heads these days have multiple options for spray patterns so you can choose which suits hey.
 
When the gas & water bills come in after this idealistic installation has been completed you may find the patten of usage changes!!

As the man of the house of course your wife will be getting up earlier than you from then on & will shower in 2 minutes, get the kids up & washed, leaving you free to rise at your normal time have a nice shower before going downstairs the enjoy the cooked breakfast she has prepared lovingly for you.
or an I being idealistic now ?
You are clearly earning too much now Mutley.
 
All these heads these days have multiple options for spray patterns so you can choose which suits hey.

Meant more the rose type ones initially re 300-200mm being better flow. That said all the good makes Grohe, Hans Grohe, Kohler and some Aqualisa offer great flow & flexibility for sure. :)
 
So, I am getting my A into G with this install now. Just wondering what the best way to install a unvented in the loft as this is going to be a lot of weight. Usually you just stick it over a load bearing wall but not sure if this is the case with a cylinder like this? Do people get structural engineers in for these installs?
 
Cross beam at least 4 each side of the cylinder even better over two supporting walls

As for size depends on cylinder l
 
Cross beam at least 4 each side of the cylinder even better over two supporting walls

As for size depends on cylinder l

Hi Shaun, thanks for the reply. It will be around 440kgs. Just been doing some calculations and 50 x 100 joists at 400mm centres and a span of 1.8 will do 0.5 KN/m2. I need around 1.7kn/m2.
 
Hi Shaun, thanks for the reply. It will be around 440kgs. Just been doing some calculations and 50 x 100 joists at 400mm centres and a span of 1.8 will do 0.5 KN/m2. I need around 1.7kn/m2.

6x2s ? I would think that would be around the spec
 
6x2s ? I would think that would be around the spec

Do you think 2x6s would be ok for this then. I can span 2 brick walls of a room below which is a 2.4 metre span in the opposite direction of the joists. The tank would probably be in the centre of this span though.

Cheers. Trying to get a structural engineer but none of them are really that interested.
 
Do you think 2x6s would be ok for this then. I can span 2 brick walls of a room below which is a 2.4 metre span in the opposite direction of the joists. The tank would probably be in the centre of this span though.

Cheers. Trying to get a structural engineer but none of them are really that interested.

I would think it would be more than good enough if you span on two supporting walls

You tried phoning building control
 

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