I have been having a weird issue with my Delta Kitchen Faucet. I previously had an issue with the hot water leaking even when the hot water heater valve was turned off.
This told me that there was an issue with the valve of this faucet where cold water was seeping through the valve to the hot water side. This would obviously cause problems over time, so I decided to just replace the cartridge.
If you want to know how to remove and clean the hidden aerators on these faucet’s, you can check out that video here.
Here is the Delta Part number RP50587. It is actually about $10 cheaper on Amazon than in Lowe’s and Home Depot.
Delta Valve Cartridge RP50587: https://amzn.to/2JXoloO
Aerator Removal Wrench: https://amzn.to/2VHuFDh