The is an older, non-electric water softener model that uses standard block salt and a compact twin-cylinder design. While a single standalone "HV3 Manual" PDF is not always hosted directly under that specific name on the official site, you can access comprehensive installation guides and brochures through authorized distributors and general Harvey resources. Installation & Operating Manuals

Because the Harvey HV3 uses a twin-tank system, it regenerates using water pressure. Proper drainage is vital.

Turn off the main stopcock and open a cold tap to drain the system.