Adequate flow?

[JohnD]

Q.
Is 3 gallons a minute OK at a kitchen tap?

Why?
I have recently fitted a new water softener. it has 3/4 BSP inlet and outlets, and is connected using "washing machine" type hoses. The old one had plastic ends on the hoses, and I see the internal bore of the old hose ends is 10mm.

The new one came with "thinner" hoses having a chromed elbow on the end with an OD of 5mm, so I presume the reduced bore wil reduce water flow. I don't know if I should be concerned.

I measured water delivery at the sink cold tap (1st floor), it filled 2 gallons in 40 seconds.

Is this within the range normally considered adequate?

I also have a shower with cold mains feed, and a utility room with sink and washing machine, on the ground floor. Everything else comes from a loft cistern 10M above ground.

p.s. You now know why I was looking for the stop-cock at the weekend

 

[gas4you]

If you had bought a hi-flo version water softener this would have had the wider internal hoses!

 

[BoxBasher]

Q.
Is 3 gallons a minute OK at a kitchen tap?

9 litres/min (2 gallon/minute) is benchmark "adequate flow" within the water industry (standard is for boundary flow, but usually measured at first incoming tap as supply at boundary will always be higher than this). Anything below this is deemed as a poor supply anythign above is class good.

 

[JohnD]

If you had bought a hi-flo version water softener this would have had the wider internal hoses!

seller offered big-bore hose kit at £25 extra but it did not occur to me that the standard ones would be smaller than on my old one.

I still have the old hoses but won't bother swapping them if the existing flow is considered OK. They just look like washing-machine hoses anyway. But white so perhaps they are special for potable water.

From BoxBasher I gather that 3 gall/min at the sink is fine.

Thanks!

 

[BoxBasher]

From BoxBasher I gather that 3 gall/min at the sink is fine.

Thanks!

I'd prefer more myself, but that is about what I get without a softener...

 

[JohnD]

The kitchen sink tap (1st floor) is close to the rising main, but has those silly 8mm tails. I just tried the Utiitly room sink (ground floor), which has proper half inch taps but is further from the main. It filled the 2-gall bucket in 35 secs so that's, umm, 3.4 galls/min at constant flow. I notice the pressure drops off in the first half-second of opening the tap.

How do you calculate the flow reduction from interposing two 5mm internal bore hoses each 1m long, compare to two 10mm hoses using the same valves? Is it likely to be worth the bother?

p.s. I am at 5m above mean sea level, if that makes any difference.

 

[BoxBasher]

I notice the pressure drops off in the first half-second of opening the tap.

Perfectly normal. The static pressure builds up against the closed washer in the tap. When you open the tap it forces the first bit of water out quickly and then settles down to a normal flow.

How do you calculate the flow reduction from interposing two 5mm internal bore hoses each 1m long, compare to two 10mm hoses using the same valves? Is it likely to be worth the bother?

Been a long time since I was in college... Exact flow rates for different bores over one meter of pipe aren't going to be that different at the flowrate you're dealing with. Small percentages will make a difference over several meters, or if a percentage of 100's litres/min but not significant enough to notice when dealing with 15 lpm.

p.s. I am at 5m above mean sea level, if that makes any difference.

Not really, it is the height below a service reservoir (if in a gravity fed area) or your height in relation to a booster/pumping station (if on a pumped system) that determines pressure levels (amongst other things...)