One shower in my house doesn't keep the water hot for longer than 2 minutes. It started recently with the hot water only coming out occasionally. So I took the faucet apart. (kohler brand). I replaced both the cartridge (Model # RGP500520) and mixer cap (Model # RGP77759). I still can't keep the water hot.


If I leave the shower off for a few minutes there will be a "build up" of hot water. Then it stays luke warm at best. I am thinking there may be a block in the pipe, but I'm no plumber. The house is realtively new - 2008.

Do you have a model number for the shower valve? Does it have a anti-skald in it? Back to you, Tom

Hi Heywaite

If you have replaced the cartridge and the cap to the shower then the next only logical step to me would be to explore other nearby faucets... may have a cross connection that is supplying cold into the hot water and is showing up at the nearest faucet (shower), right?

Tell me what lavatory faucet(s) you have... is it (or are they) a single handle faucet? If it is (or they are) a single handle faucet then most likely one of the mixer cartridges at the faucet(s) have gone bad and needs to be replaced.

This is easy enough to test by simply shutting off the hot water shut off valve under each sink in the bathroom (or sinks in the bathrooms if you have back to back bathrooms) and checking to see if the shower valve is fixed, right?

Start there... post back as you work through this and we'll see if we can help, OK?

Mark