hi I live in SW14 in London We have new water mains in the street which thames water did last year, but the pipe in my front garden to my house will date back to the 60s.... The flow rate from the kitchen mixer tap showed as 12 Litre/min (bucket test last night). Given it looked poor and the thames water minimum is 1 bar/9L per min, this sounded poor to me. I plan to measure the actual pressure this weekend (I need to buy a gauge first). Before I spend 3-5K on a pressure fed brand new heating system (combi or megaflo), is there any way to know what I would get if put a new MDPE line from the mains in? i.e. Is there any way to check whats available from the street before I go to any bother and expense of new pipes etc?
Did the pressure/flow improve after they fitted the new mains pipe? You could ask neighbours in the street who have had a new MDPE pipe fitted what the results were. Contact the water company and ask them what you would hope tom expect. 12/l/min appears low for new mains pipe, even if through a small pipe across the garden. Do not go Megaqflow. Go for an ATAG 51KW two bathroom combi, the ATAG A325EC or Avantaplus 39C.
Walter is a * Thames won't tell you what you'll get, but you'd be better off judging it by what connects the main to the house now. I would be surprised if it was bad, but they are known for lowering pressure due to localised water leaks. [Edited by: admin]
You will be unlikely to get better pressure, London is notorious for low pressure better to fit a conventional system oh and whatever you do do not fit anything recommended by Walter!
flow rate can be affected by the actual kitchen taps them selves, is there an outside tap you can test, to see if you get same results 12 litres per metre
If the flow cannot be improved, consider a mains pressure accumulator. The bathroom changers here have seen one.
Well the OP could spend a fortune on a Walter System or he could take practical advice from people who know......
Thanks for the suggestions, I tried a neighbour last night and they have their original main too - but they get 20 L/Min (at their kitchen tap, so there is a chance that its better still on the pipe itself). I also looked at where my water comes in to the house and that is 15mm copper pipe... I will try another neighbour or too tonight. Cos I am doing a loft conv, I am trying to do away with tanks in lofts (for space + I will have have my second bathroom in the loft at the same level) and I don't want an electric pump (as while pressure is great, I am in a terrace and my current shower pump wakes them up when I show at 6am).
Well it won't be copper to the water main. If it's lead they are often compressed over time. As said you really need to measure from an outside tap or, as I do, disconnect at the internal stopcock and measure
I am guessing lead had been phased out by the 60s hadn't it? It looks like 15mm copper coming up through the kitchen concrete floor, though i am guessing its the old money equivalent - 1/2 inch or something. Either way it looks quite weedy As to the pipe outside I have yet to dig a little trench and see whats between the house and the street main. God knows what driven on the lawn over the years so crushed or scaled up it may well be. thanks again for the tips
if you going to the effort and expense of converting loft, might has well do job right, and just replace mains with 25mm mdpe from street,job done for next 50 years or so.
If your neighbours are getting higher flow rates then a new pipe should sort you out. The question is how much? Replacement schemes vary considerably and are usually based on lead piping. It is worthwhile asking though. The national standard for supply is is 9l/min at 1 bar (down to 0.7 on occasion). This is miserable and in most cases exceeded but it means you can't use it as an argument. The pipe from the mains is in two parts: the bit from the mains to the boundary of the property usually with an external stopcock (communication pipe) and the bit from the boundary to the internal stopcock (the supply pipe). The communication pipe is the water company's problem and the supply pipe is yours. You can sort out the supply pipe yourself as long as it conforms with the company's guidelines and leave the company to sort out its bit.
Try these - http://www.sandysplumbing.co.uk/ they will a offer free quote to run a new MDPE into your home. As a price guide, they recently done a new 25mm upgrade for client in SW8 using a mole, for £600+vat That was approx 4m run into a basement with new stopcock and connected to existing services. Total bargain in my book.
Thanks for that - its good to get a rough idea of prices. I did call the thames water who said if was a few hundred quid just for a survey and then they knocked that off the price of the actual work they quoted you for (sounded like a lock in to me, as once your 2-300 invested its hard to walk away) Either way I will likely have to get it replaced, i will have a qualified person do all the work. However the answers I got on the forum will help me ask the right kind of questions. I will update this thread again once I get something in place.