You put new plumbing in the pex and every room has real good water pressure but kithcen hot runs really slow?

There are a few possible reasons why the hot water pressure in your kitchen is low while the other rooms have good pressure.

1. Clogged faucet aerator. The faucet aerator is a small screen located at the end of the faucet spout. It helps to mix air with water, which can improve the flow of water and reduce splashing. However, if the aerator becomes clogged, it can restrict the flow of water, causing low water pressure. To clean the aerator, unscrew it from the faucet and rinse it under running water.

2. Faulty cartridge. The cartridge is a component of the faucet that controls the flow of water. If the cartridge is damaged or worn out, it can cause low water pressure. To fix this, you will need to replace the cartridge.

3. Kinked or damaged supply lines. The supply lines are the pipes that carry water from the main water line to the faucet. If the supply lines are kinked or damaged, it can restrict the flow of water, causing low water pressure. To fix this, you will need to replace the kinked or damaged supply lines.

4. Low water pressure from the main water line. If the water pressure from the main water line is low, it can affect the water pressure in your entire home, including the kitchen. To fix this, you will need to contact your water supplier and ask them to check the water pressure.

If you have tried all of these solutions and the hot water pressure in your kitchen is still low, you may need to call a plumber for help.