I recently had a plumber install a new Kohler kitchen faucet model #K-R648. The hot water pressure is about half the cold water pressure. I called Kohler and they are sending me a new cartridge. Do you think this will take care of my problem? Is it easy to install a new cartridge?

Thanks for your help.

Yes it sounds like there are debris inside your faucet,I would suggets to close the angle valves under the sink remove the cartridge turn on the water hot then cold for a few seconds to flush the debris and check if you have a good flow, install the cartridge and check if it is OK now, if not then you change the new cartridge when you receive it, it is very simple to replace the cartridge, good luck.

John

Agree with Afaroo: it may be dirt in the cartridge. But also, it may be kinked flexible hot water supply line under the sink. If not looped properly, hot water flex lines will kink very easily.