Shower flow restrictor won't fit kitchen faucet

[rmcmullan]

Hello,

As part of a green business certification, I'm trying to reduce the flow of our kitchen faucet (1/2" FIP) to 1.5 GPM (without replacing the whole faucet). I purchased a flow restrictor intended for a shower (Shower Adapters, 1.5 GPM Maximum Flow Rate, Female 1/2"-14 NPT x Male 1/2"-14 NPT) after researching that 1/2" NPT is the same as 1/2" FIP). And from what I understand 14 threads per 1/2" is the standard thread density as well.

So I tried to install it on the cold water line, unscrewing the standard supply line with the 1/2" FIP fitting. I tried to thread the supply line to the flow restrictor and it works with no problems. I then unscrew it and try to thread the adapter to the kitchen faucet intake and it won't go more than a 2 rotations before sticking and resulting in the copper line to the faucet rotating/deforming. When I restore the water pressure I get water spraying from the link between the flow restrictor and the kitchen faucet intake.

Thinking there was something wrong with the part, I tried putting it on a shower head and both sides screw in with no problem.

What am I missing? Why can't I get the adapter onto my kitchen faucet intake? I know that it was intended for a shower, but shouldn't the NPT standard be... ...standard? Thanks for anyone who has a hunch on this.

 

[Reach4]

As part of a green business certification, I'm trying to reduce the flow of our kitchen faucet (1/2" FIP) to 1.5 GPM (without replacing the whole faucet).

To restrict flow on a kitchen faucet, that is usually part of the aerator. If you reduce the flow of the supply lines, that would restrict just hot or just cold. If you restricted each to 1.5, that restricts you to as much as 3.0 gpm.

So before addressing how to adapt a shower restrictor to a kitchen faucet, you might redefine the problem.

 

[Sponsor]

 

[rmcmullan]

I totally agree that the aerator would be the preferable way to do it, but our faucet has a proprietary head (a pull-down model) that doesn't allow for swapping the aerator. So, instead of spending $200 on a whole new fixture, I wanted to try something less expensive. My reasoning was that most of the water use is when we're spraying cold water to rinse dishes, so if the water is on full cold, the flow restrictor on the cold water line would do the trick. I'm open to other ideas, but haven't found any that don't start with "replace your whole faucet".