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View Poll Results: Flow Rate is
Very Low 2 14.29%
Low 3 21.43%
About Average 5 35.71%
High 0 0%
Very High 4 28.57%
Voters: 14. You may not vote on this poll

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Old 20-03-2017, 11:38 AM   #1
dtd00
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Water Pressure Pathetic?

I have for some time believed my water pressure is pathetic but yesterday I tested the flow rate by filling a 5 litre bucket and timing it. I was attempting to wash the car but with a light breeze the water pressure was too low to reach across the car! I also have a karcher pressure washer but it barely works, presumably due to the incoming water pressure?

From the kitchen tap the bucket filled in 20s so 250ml/sec
From my outside tap (where the hose attaches) 20s so 250ml/sec
From the hose it was 45s so 111ml/sec
I unrolled the hose completely and found my useless hozelock hose had twisted/kinked close to the reel. After grappling with it and straightening it the time reduced to 32s so 156ml/sec

I think there is a definite issue with my hose and a possible issue with the flow rate coming from my taps.

1. Does my flow rate (250ml/sec) seem reasonable or should it be higher? What is a normal level?
2. Can anyone recommend a hose that will at least get me to my tap flow rate?

TIA,
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Old 20-03-2017, 11:55 AM   #2
GleemSpray
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Sundays.

That's the day that Water Supply company's deliberately turn the pressure down a bit, because that's the day that people use hosepipes and PW's the most. So less water gets used and the Supply companies terrible leakage figures even themselves out a little.

The cover story, if anyone notices, is that reduced pressure is to assist in fixing leaks.
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Old 20-03-2017, 12:14 PM   #3
dtd00
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Interesting idea, I will check it again today.

I should probably say my low pressure/flow issue is a constant problem, not limited to Sunday's.
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Old 20-03-2017, 12:32 PM   #4
fatdazza
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Ok,

so from your kitchen tap a flow of 250ml per sec, that is 15 litres per minute.

Depending on your PW, the flow required is normally around 7 to 10 l per minute so it should be more than adequate.

If you are a United Utilities customer (Manchester?) their standard for acceptable pressure is to fill 4.5 litres in 30 secs, so you are within that.

The pressure and flow from your hose pipe will be reduced depending on the length of the hose pipe and the number of flow restrictions you create along it (e.g kinks or elbows). To improve flow from your hose, you need to reduce the friction from the water flow, so a shorter, wider hose with a smooth inside surface.

Also make sure that the feed to your outside tap has as few restrictions a possible (some of the DIY clamp on kits only cut a small hole in the cold supply where as a proper T off would improve flow)
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Old 20-03-2017, 06:43 PM   #5
Mr K
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I have the same problems here

It is pointless trying to shower in the morning as everyone else is running water so my pressure is down as I am at the end of the line

Anglian Water say it is OK.

Sorry mate if you are at the end of the line and there are leaks [ as there usually are ] your pressure will be low and there is little or nothing you can do about it.
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Old 20-03-2017, 07:15 PM   #6
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You'll find that the water board will do a lot of maintenance on a sunday and will down down the pressure so the guys can work on the pipes safely.
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Old 20-03-2017, 08:25 PM   #7
Caledoniandream
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Check that you have no "stops" in your hozelock connectors, they are very restrictive.
Another thing to check on your Karcher is the inline filter.
Take your connector off, and pull your inline filter out, clean and put back.
Your flow should be enough for a pressure washer.
Make sure there is no kinks in your line.
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Old 21-03-2017, 11:02 AM   #8
Sh1ner
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The flow at the hose will never reach the flow at the tap although there are a few things you can do that can help get you closer.
What diameter and length of hose are you using? The larger the diameter and shorter the hose the more consistent and better the flow.
I found the change to 19mm i/d hose useful and the pressure when in use shows much less variation when using a handheld nozzle. With the smaller 13mm hose the pressure builds in the hose but falls away quickly when the nozzle is opened. With the larger hose the pressure/flow remains much more consistent.
As CD says if you are using connectors with stop valves check the hose connections are actually opening fully when they are locked together.
As much as I like and use Hozelock stop connectors they are really inconsistent for this. Quite why they need to reduce the diameter so much and open the valve so little is just crap engineering.
It is worth taking the two parts off the hose and the tap and checking how much the valve opens when mated.
When I checked mine I found it necessary to make some small shouldered rings that press into the male part to extend it by a mm or two so to fully open the valve.
If you do away with the valve altogether then you can also drill out the connector a little and ease any restriction on the flow that way.
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Old 21-03-2017, 11:01 PM   #9
dholdi
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WRAS regs state 12 litres per minute from the main.
That's 200 ml per sec so your rate at the tap is fine.
I suspect, as others have suggested, your issue lies elsewhere.
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Old 22-03-2017, 07:09 AM   #10
fatdazza
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Quote:
Originally Posted by dholdi View Post
WRAS regs state 12 litres per minute from the main.
That's 200 ml per sec so your rate at the tap is fine.
I suspect, as others have suggested, your issue lies elsewhere.
Not strictly true re the regs:

There is a Water Industry Guaranteed Standards Scheme that requires a pressure of 7 m static head in your communication pipe. If they fail to meet this standard you are due a compensation payment. (which doesn't help that much if you want to wash your car
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