Got a new water heater and now the shower is messed up

I installed a new water heater yesterday, and after doing so, most of my faucets in the house were clogged with gunk. I removed the screens and cleaned them and everything seems to work now excpet for my shower. I remvoed the showerheads and checked for gunt, but they are clean. Cold water flows out fine, but when I crank up the temperature, it stays cold and the pressure drops. Are there internal screens that I can clean for gunk? I have a Kohler k-401 mixing valve in my setup.

Thanks for any help you guys have on this!

Sounds like you got gunk inside the Kohler k-401 and that you'll have to try cleaning it.

thanks for the reply.

I'm at work now and am trying to figure out what I'm up against tonight! Would you happen to know if they are relatively easy to take apart and clean? Are there screens int here somewhere? I got as far as removing the outer covering and the valve looked massive and like nothing I had seen before. I didn't try taking it apart yet.

Could be a some debris in the cartridge of the mixing valve.

???

Good Luck