I have a Price Pfister shower where the hot water is not hot anymore, just warm. Problem just started and does not effect other faucets in the house. If I replace the valve cartridge will it fix this? If not, what else could it be? Shower was only remodeled 5 years ago.

(Previously posted a couple days ago asking for help identifying the shower valve maker--and thanks to all who helped with that!).

i might first check for debris in the hot side.
shut off water, pull cartridge out, turn water back on, put back cartridge to see if that helps..
if not then change the cartridge

It might depending on which cartridge it uses.

Replacing the cartridge will take care of your problem. The 974-042 cartridge should be readily available in Ca. That is where Price Pfister is located. Their warranty number is 1-800-732-8238

Thanks, ALL! And yes, @marliman, you were spot on with the model number for the cartridge valve. Saved me considerable time as I bought the valve before I arrived at the worksite.

It took all but seven minutes to replace and they now have hot water. Also, I wasn't aware but this particular valve has a temperature control on it. So they wanted even hotter water so I adjusted the setting since I was at it. Happy customers.

There appeared to be some whitish debris in the old valve but not to account for the lukewarm water. But I think I figured out why (in my naïve opinion). The two square gaskets on the back side were worn slightly and I'm not sure how those wear down except for age. So I guess there was crossover from cold to hot. Tell tale sign was when I turned back the water back on I got some black soot out of the tub spout (and the gaskets darkened my hand a bit when touching them).

I can't tell you how much I love this forum for the quick responses and the invaluable expertise. I am a mere jack of all trades handyman with a specialty in electrical. I've only taken on more and more plumbing jobs with all the help from this website.

Thanks again,

@120volts



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