Our Price Pfister 809-7C Avante Tub / Shower single control was leaking behind the control knob. I was unable to find any information on the internet for replacement parts so I call Price Pfisters consumer service help line. (1-800-732-8238). I told them my problem and they sent me a new 974-2920 control cartridge free of charge. Got it five days later. Great service!
A very good suggestion below from tripjet999. After you remove the old valve. Stop and use a light to check for any debris/foreign material inside the chamber, prior to replacing valve.
Post time: Jun-20-2017