how to trace water pipes, and understand how/what generates/restricts water pressure/flow | |
I recently moved into my home, which currently has a conventional boiler with a water cylinder in the airing cupboard and one large and one small tank in the loft. It is a 3 bed semidetached house on fairly modern development area (about 10 –12 years old), and believe my boiler and heating system to be the original fitted when the house was built – and hence, apart from the other plumbing work which I hope to be able to do, the current boiler needs to be replaced at some time in the near future.
It has a HMAX 3 bar (2 bar output) shower pump to power water to the on-suite shower (without which the pressure/flow is hardly enough to provide a reasonable shower…although better then the bathroom bath mixer tap shower-head). The main bathroom bath mixer shower is almost useless to use as a shower, as the water pretty much falls out of the showerhead (despite water flowing from the tap element of the mixer unit at a significantly higher rate. Both the on-suite shower and the main bathroom mixer tap/shower head of the bath, are upstairs on the same floor as the water cylinder tank.
I’m an enthusiastic diy’er, and even though I have the tools and skills to change a tap, and do many jobs around the house, I have never really been able to fully understand the main principles which are necessary to know understand what factors need to be considered before identifying how to consider any options possible for choosing the different heating systems available (the conventional ‘gravity’, the combi/condenser, vented or the closed system that produces the same pressure/flow to the hot and cold taps throughout the house (don’t really understand this one at all) or the requirements in terms of pressure/flow of each of the different boiler systems. I have contacted the water supplier, and they say that the area I live in has no problems regarding water pressure from the mains to the house, and I have had plumbers confirm that my water pressure is normal. And I realise that it is pretty much ‘horses for courses’, which system I should go for but get confused when trying to take on board the water pressure/flow, or how the difference in the diameter of pipes affects and/or inhibits flow/pressure (I understand that larger pipes allow more water to flow, but when I look around my home I have three different sized pipes which don’t always make sense to me. Ie I know that ‘rising mains’ piping should principally be 22mm, but some piping with water being pushed upwards is only 15mm – why might this be? And that these 22mm pipes are used to generate the ‘mains’ flow water pressure throughout the house, but some parts of the house have 22mm, some have 15mm, and some have the smallest piping (mainly fed to the radiators). When I look in the loft to try and work out which pipe is the ‘mains’, and why each pipe goes wherever it goes, but it’s like spaghetti junction – so unable to know which are mains, But want to be able to understand what pipes go where and why, as I don’t want to have anymore unnecessary additional piping if possible to achieve whatever is the best solution for my home.
And one part of the equation is how the flow rate is based on a specific temperature rise – usually 30˚C or 35˚C. If a greater temperature rise is required, the flow rate must be reduced. Conversely, a greater flow rate can be obtained if the temperature rise required is less. Then there is the choices of boilers which give different kW options.
E.g. details copied from a plumbing site But what original flow rate is it based on, and how can these figures be based on anything other then sweeping generalisations:
A Combi with an output of 23kW gives a flow rate of 9.4 l/min for a temp rise of 35˚C but;
A flow rate of 8 l/min gives a temp rise of 41˚C
A flow rate of 10 l/min gives a temp rise of 33˚C
A flow rate of 15 l/min gives a temp rise of 22˚C
If possible could any information explaining how pressure, power and flow be assessed by myself so I can know precisely (or work out a reasonable ‘guestimate’), and how I can make sense of any of the information in order to work out what I need to do to obtain reasonable pressure/flow to both my on-suite shower and the shower in my bath(room), as I have had three different recommendations from 3 plumbers. One recommends just replacing the current boiler with a new conventional boiler, saying that it doesn’t make sense to ‘exchange an Orien for a Skoda’ system, suggesting that condenser boilers are unable to provide the pressure/flow that a conventional gravity system gives with the existing shower pump I have. (But my problem with this theory is that I somehow have to get the pump to generate pressure to the bathroom shower (which no doubt means pulling up carpets, floorboards etc). The second option I’ve been given is to throw out the shower pump (as I’ve been told it is not possible to use a shower pump with any combi condenser boilers…is this accurate?) and just replace it with a newer model of the same type. The third option I’ve been given is a unvented hot water mains system. I’m even more confused about this option and don’t understand why having this system will provide the same pressure/flow from the hot water tap as the cold water taps, in if I understood it right, a ‘clossed’ system. And if this really is possible, why is it not possible using the combi or conventional boiler system to achieve this type of continuous equal pressure/flow.
I can do simple to reasonably complex plumbing jobs, but anything relating to installation of boilers or serious I get the professionals to deal with it. I appreciate and know these are a lot of questions, but I’ve never really been able to make anywhere near an informed decision, and consequently each time I contact a plumber as to which boiler they recommend is best for my home – I’m so confused myself, it makes it almost impossible for them to help me without getting too frustrated!
I understand everyone has their own preferences, I just want to be able to know which to go with, which in turn would help me identify a plumber who has the same preferences of systems, to maintain my system (apart from the work I can carry out myself.
Any/all information in simple to understand layman’s terms would be really appreciated.
Many many thanks
Mike
NB I’m not worried about other water sources being used at the same time, as girlfriend or friends visiting rarely need to use the facilities at the same time.
Answers:
No answers to this question!
Back
Add Your answer to this question: | |
|
|
 |
Powered by Yahoo! Answers
|
|
|
» Ask a question
» Answer questions
|
