Fixing low flow kitchen faucet problem

[Tim Brennan]

14 years after we had our kitchen fitted I’m finally getting round to fixing a problem. It’s been with us since the start.

Our kitchen faucet only gives about 1.5 L per minute of flow.

About 1 foot away from the kitchen sink on the other side of the wall is an external garden tap which produces around 10 L per minute. So the problem seems to be with the plumbing rather than the mains pressure.

I started by removing the aerator at the end of the faucet. This improved the flow up to about 4 L per minute. I then looked underneath the sink to see what all valves are installed. Please see attached photos.

I don’t have a huge amount of experience with plumbing, but I can see that the ball valves are not the full bore type. That’s one thing I could potentially change, but would it give me the desired flow of about 10 L a minute? Should I be looking to swap out the aerator for a higher flow rate version? Or maybe do both of these? Or something else?

I can see other brass valves but I don’t know what these are or if these are the problem.

 

[Tim Brennan]

Here are three photos

 

[Peter Kelly]

Is the flow rate equally low on both hot and cold? Might just be a matter of changing the fixture if so.

 

[Holzhacker]

Unscrew the aerator at the end of the faucet. The screen is probably clogged. Take the aerator off and check water flow. Clean the screen or just cut it out.
If flow is just as bad with aerator off then you likely have a kinked supply line or a somewhat clogged shut off valve.
Likely the aerator though.

 

[Packard]

Unscrew the aerator at the end of the faucet. The screen is probably clogged. Take the aerator off and check water flow. Clean the screen or just cut it out.
If flow is just as bad with aerator off then you likely have a kinked supply line or a somewhat clogged shut off valve.
Likely the aerator though.

I have found that soaking the aerator in a calcium solvent works well too.  It will usually clean 100% of the white calcium accumulation. Of course your water will be different and may have other minerals causing the problem,

I use CLR.  They want you to use it and then pour it down the drain.  I find it is still potent after 3 or 4 uses.  I use it on shower heads too.
https://clrbrands.com/Products/CLR-Household/CLR-Calcium-Lime-and-Rust-Remover

 

[Cheese]

I'm just curious as to what you are doing in the kitchen that needs a water supply of 10L per minute.  [smile]

That's a flow rate that would water a garden...for filling a pentola to cook pasta, a flow rate of 2-3L per minute works well.

As far as aerators go, that's usually the limiter on water flow. Contact the water supply fixture manufacturer to find out what flow rates are available. Because of local water restrictions usage, the flow rates will vary.

Kohler usually produces at least 2 different aerators with 2 different flow rates and sometimes offers 3 different options for all of their faucets.

 

[woodbutcherbower]

[member=21939]TBR[/member] Swapping out those isolating valves for full-bore ones will make a huge difference. A regular 15mm isolating valve only has a 9mm bore. When you loosen the compression nuts and remove the valve, you’ll find a copper or brass ring (called an ‘olive’) tightly squeezed onto the pipe ends. Wrap the olives with 6-7 turns of PTFE tape before you insert the new valve and tighten up the nuts. For belt & braces, also apply a good smear of Fernox LSX jointing compound (you’ll find it at Screwfix) to the olive once you’ve taped it up. The best UK product to use for unclogging mesh tap filters is kettle de-scaler. You won’t need much - so get your kettle cleaned out as well  [big grin]

FYI - the brass valve with the black cap is a one-way non-return valve. These have to be fitted by law when a kitchen tap is fed from the same line as an outside tap. It’s there to ensure that any contamination occurring on the outside can’t siphon back and enter your drinking water. They contain a spring plunger and a couple of O-rings which clog up. Replace that as well - Screwfix once again.

The other thing I see is that your tap tails (the flexi tubes connected to the actual tap) only look to be 8mm bore ones. 10mm or 12mm bore are also available. Normally adequate - but the installer’s also then hooked these up using additional flexis instead of hard-piping it. Any small-bore flexi in a system will reduce the flow. With so many possible bottlenecks as listed above along with a pretty messy overall installation - I’d honestly get a plumber out to re-do the lot.

Hope you get fixed up.
Kevin

 

[Crazyraceguy]

There's another of those words that we use differently. In the US, we only use "olive" for the tiny lines on things like oil pressure gauges or hydraulic brake lines on bicycles. On larger diameter tubing, like water supply lines, it would be called a "wedding band". 

 

[Cheese]

There's another of those words that we use differently. In the US, we only use "olive" for the tiny lines on things like oil pressure gauges or hydraulic brake lines on bicycles. On larger diameter tubing, like water supply lines, it would be called a "wedding band".

Now that's funny...I've never heard either of those words used with reference to compression fittings.  [smile]

I always referred to them as compression sleeves & compression nuts.
https://www.supplyhouse.com/Bluefin...MIvf2bjumZhgMVZBetBh2Zkg_yEAQYBiABEgI8yvD_BwE

 

[leakyroof]

There's another of those words that we use differently. In the US, we only use "olive" for the tiny lines on things like oil pressure gauges or hydraulic brake lines on bicycles. On larger diameter tubing, like water supply lines, it would be called a "wedding band".

Now that's funny...I've never heard either of those words used with reference to compression fittings.  [smile]

I always referred to them as compression sleeves & compression nuts.
https://www.supplyhouse.com/Bluefin...MIvf2bjumZhgMVZBetBh2Zkg_yEAQYBiABEgI8yvD_BwE

I first ran into Compression Rings being called Olives when I started working on Land Rovers. It was standard in both technical and Parts Dept descriptions of the compression ring... [big grin] [big grin]