Improving water pressure on a private water supply??

[Onetap]

I'm not into pumps, etc, but how do I identify the flow rate? Is it simply taking the distance from the pump to the height of the cold water tank inlet (as that is the highest point)?

Errrrrr, no.

The pump will have a characteristic graph of flow rate against pressure difference. At a certain pressure difference across the pump, you will get a certain flow rate. At a low pressure difference you get high flow rate, high pressure difference gives low flow rate. The pressure difference is often expressed as the equivalent height/head of water.

Similarly, the pipes, from pump to tank, have a resistance at any given flow rate; the resistance is due to friction and appears as a pressure loss. A high pressure difference across the pipe gives a high flow rate, low pressure difference gives low flow. A small bore pipe will have a big resistance compared to a pipe a size or two bigger at the same flow rate.

Have a look at pressure booster sets.

These used to have duty and stand-by pumps. The pump was switched by a pressure switch. The pressure vessel(s)/ expansion vessel/accumulators were intended to provide a pressure reserve/buffer, to reduce the number of pump starts caused by small water draw-offs. The motors don't like frequent starts & will over-heat.

Speed controlled pumps have become common on commercial sets, but probably too expensive for a small installation like this.

IMHO, I'd install a new byelaw 30 compliant tank and get it into the loft space if possible. If thoroughly insulated, the water stored in it should be of potable quality, if there's a turn-over at least once every 24 hours. The tank needs to be well insulated to avoid it freezing. You'd need to be sure the plumbing was of suitable standard (no gacky old lead pipes or lead-soldered fittings). I'd take the potable supply from the tank; this should minimize the frequency of pump starts and extend the life of the pump. Pump operated by level switches or use an Aylesbury float valve (on/off operation) and a pressure switch at the pump set.

 

[Balenza]

Doitall wrote

the accumulator will stop the pump cycling, hold a constant pressure, and as a bonus prolong the life of the pump.

Yes and its already fitted at the pump set as the OP has stated.
Until you know what the pipesizes are and the distances they run over you cannot just go banging in expensive and troublesome accumulators.

 

[Balenza]

gas4you wrote

What ever you say you will be wrong , overcharging the customer and ripping them off. in fact if you done a job for him for nothing you would be charging him too much according to him
__________________

Thats rich coming from someone who doesnt understand modern condensing boiler pipesizing methods.

 

[simond]

It would appear that you just want to try and discredit worthy suggestions and individuals, rather than come up with any viable solutions yourself.

 

[doitall]

Now, the house is an old croft, which has a traditional heating system (gravity fed) using the cold water tank (25gallon) and expansion tank (4 gallon) in a cupboard upstairs (no loft).

Now, the pump outside runs whenever the pressure drops below 2 bar and stops when it reaches 3bar.

If, say I were to flush the toilet then wash my hands in the sink beside it (Only 1 toilet in the house) and switch on the cold water tap, the water pressure reduces dramatically and actually stops filling up the toilet cystern until the cold water tap is switched off.

I've got the house in pieces at the moment, doing every room up so I was thinking of changing out the hot & cold water tanks for a Main's Pressure Hot water tank (Megaflo, for example). Will this improve my water flow for the cold water too, or will I need a larger pump outside to increase the water pressure initially?

Thanks all!

Quote from the Op for Ballski.

The pump is only suppling the storage tank and at present has NO influence on the outlets, your questions are irrelevant.

If the Op goes down the unvented/direct fed cold road, the accumulator will prevent the highs and lows at the taps, and increase the pressure/flow considerably.

 

[doitall]

Doitall wrote

the accumulator will stop the pump cycling, hold a constant pressure, and as a bonus prolong the life of the pump.

Yes and its already fitted at the pump set as the OP has stated.
Until you know what the pipesizes are and the distances they run over you cannot just go banging in expensive and troublesome accumulators.

Where has the Op stated he has an accumulator fitted, he hasn't the pump is controlled by a pressure switch that switches between 2 & 3 bar.

For your information the pump sucks the water from the well and deposits it in the storage tank.

 

[Balenza]

Doitall wrote

Quote from the Op for Ballski.

The pump is only suppling the storage tank and at present has NO influence on the outlets, your questions are irrelevant.

The OP also wrote

From there it T-ees off to the kitchen tap / washing machine

We dont know what supplies what at this stage so I would say my questions are relevent especially if he is considering installing a UV cylinder ? (or should I say "pressure bomb" with all that I read on these forums about them)
If you had any knowledge in plumbing you would know this.

 

[Balenza]

Wurzel Gummage wrote

Where has the Op stated he has an accumulator fitted,

The pump also has a large tank attached (I guess that keesp the presure up) It's called a Varem, 20l capacity, 10bar MWP, Pre-charge 2 bar

 

[Balenza]

It would appear that you just want to try and discredit worthy suggestions and individuals, rather than come up with any viable solutions yourself.

Its good craic aint it .

 

[doitall]

Wurzel Gummage wrote

Where has the Op stated he has an accumulator fitted,

The pump also has a large tank attached (I guess that keesp the presure up) It's called a Varem, 20l capacity, 10bar MWP, Pre-charge 2 bar

It has a 20 litre expansion vessel as any negative head pump would.

 

[Balenza]

Wurzel Gummage wrote

Where has the Op stated he has an accumulator fitted,

The pump also has a large tank attached (I guess that keesp the presure up) It's called a Varem, 20l capacity, 10bar MWP, Pre-charge 2 bar

It has a 20 litre expansion vessel as any negative head pump would.

Expansion vessel,Accumulator,. same thing buddy.

 

[doitall]

Wurzel Gummage wrote

Where has the Op stated he has an accumulator fitted,

The pump also has a large tank attached (I guess that keesp the presure up) It's called a Varem, 20l capacity, 10bar MWP, Pre-charge 2 bar

It has a 20 litre expansion vessel as any negative head pump would.

Expansion vessel,Accumulator,. same thing buddy.

Don't think 20 litres will make much difference to anything, especially an accumulator.

 

[Balenza]

Doitall wrote

Don't think 20 litres will make much difference to anything, especially an accumulator

Some good reading material here crapitall.
http://www.accumulators.co.uk/accumulators/Accumulators.htm

 

[simond]

Ironically, Balenza, YOU are the person that should be reading the material on the 'accumulators' web site.

Is there a website we can refer you to where it advises to keep your mouth shut and your bowels open about things you know nothing about?

 

[chrishutt]

Ah, the good old accumulator debate resurfaces!