Current mains pressure and flow rate is 1.5 bar and 16 ltr/p min. respectively. I need to increase the flow rate to at least 20 ltr/p min. as a basic requirement for installing an unvented hot water system (megaflo). Before outlaying the expenditure for doing this, can someone who has done it tell me whether replacing the existing lead pipe from the outside mains into the property with say a 25mm or 28mm blue pipe might give me the extra flow that I need? The rest of the pipework in the property is 22mm (except those that tee off to the sink and garden taps are 15mm).
Increasing mains flow rate
- Thread starter lxbn
- Start date
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find out from your local authority / water provider what the static and running pressure is. If it is supposed to be higher than you've measured then maybe changing the pipework would help ( 25mm MDPE feed into house ) because the lead pipe may have been compressed somewhere underground.
The mains pressure of 1.5 bar was measured by a plumber at a sink tap with a device he strapped to the tap and turning the tap on. I'm guessing that this would be the static/standing pressure as opposed to dynamic?
Regarding flow rate, I've seen posts here where it is measured by adding the output from all taps on the mains turned on at the same time. Is this significantly different from the measurement taken from one tap and is the cumulative rate a truer reflection of the actual flow rate - or is there no difference. I have three taps on the mains but the measurement was taken from one tap - the one with a long 15mm run from the mains tee.
I have spoken with Thames Water who are sending me some literature about the supply and services (with costs) for the property. I will be able to put more informed questions to them once I've got it. They also do the whole job of replacing the lead pipe themselves - although perhaps more expensively but without having to co-ordinate and waiting for the final connection.
Regarding flow rate, I've seen posts here where it is measured by adding the output from all taps on the mains turned on at the same time. Is this significantly different from the measurement taken from one tap and is the cumulative rate a truer reflection of the actual flow rate - or is there no difference. I have three taps on the mains but the measurement was taken from one tap - the one with a long 15mm run from the mains tee.
I have spoken with Thames Water who are sending me some literature about the supply and services (with costs) for the property. I will be able to put more informed questions to them once I've got it. They also do the whole job of replacing the lead pipe themselves - although perhaps more expensively but without having to co-ordinate and waiting for the final connection.
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look on the WRAS, website for a local approved plumber,he will be able to get the job done as quick and possibly cheaper
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