In order to insure the integrity of a cartridge valve assembly and its reliability, care should be taken during the installation process. After removal from the package, make sure to keep the cartridge clean. Seals should be inspected and lubricated before threading it into the valve body. Proper torque is important in assuring the valve does not come loose. Also, over torqueing can cause the cartridge to stick. If the valve is solenoid operated, proper torque on the coil nut will also keep is secure, without causing valve damage and sticking.
Read this PDF document on cartridge valve installation and torque values for proper step-by-step instructions.
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