Possible Solution To Low Flow rate?

[nfl_1990]

Hi,
I am in the situation where the water pressure at the outside stopcock is 4 Bar with a 30 LPM flow rate. However inside the house I do get 4 bar pressure but through timing how long it takes to fill up a 10 litre bucket I only get 8.2 LMP downstairs and 6.6 upstairs (not sure if this is a very accurate way of ding this). On top of this I have an old boiler that in the first quarter cost me £160 in gas bills on top of the £49 I am paying a month. Also the boiler I currently have heats water in a tank (i.e. its not instant water when I pull on the hot tap), and the new boiler is a gas combi (i.e. no need to use the immersion tank any more). The plumber who has sourced the boiler has told me that the minimum flow rate has to more than 11 LPM.


So my question is can I use a single impeller pump to increase the flow rate of the cold feed into the new boiler? My reason for asking is because I am aware I have a 15mm supply from the outside stopcock and I am looking at extending the house so I will replace the pipe when I come to do the extension but that will be in a few years. So is this an acceptable short term solution?


Thank You,
Nathan

 

[Dotty]

No.

Forget the combi, look at a system boiler and unvented cylinder plus accumulator.

 

[MarkAqua]

https://www.buyaparcel.com/p/mains-...-fed-pressure-booster-pump-allows-the-use-of/

Something like this might be suitable. However without seeing your complete situation then it's hard to say. Get some advice off plumber who sourced your boiler

 

[MarkAqua]

But before you do anything get a proper reading Flow Measure Cup - Toolstation

 

[Nostrum]

You don't need more than 11lpm, your boiler is more likely limited to 11lpm Max flow rate due to its maximum performance.

It will work with much less, usually 2-3lpm to activate the hot water function.

You can't just pump a cold main directly as you have suggested, it won't comply to water regulations.

There must be a serious restriction to drop the flow rate to that over such a relatively short distance, have you checked the obvious?

If so, re-think your plans, combi's aren't always be best solution, even if that's what your plumber is saying.