The BWT bestflush valve is recommended to install after the BWT besthead to easily run a few liters of water when replacing new filter. It is highly recommended when using BWT water filters of size X and higher to relieve pressure when changing the filter. Washers included. Why You Flush a New Filter Before Use — and Why That Needs a ValveWhen a new BWT filter cartridge is installed, the first few litres of water passing through it carry loose carbon fines and media particles from the manufacturing process. Running those litres to a drain — rather than directly to your espresso machine — prevents those particles from entering the machine's pump, boiler, and internal waterways. Without a dedicated flush valve downstream of the Besthead, this flushing step requires either disconnecting the hose to the machine (awkward and creates a leak risk) or running the flush water through the machine itself (defeats the purpose). The BWT Bestflush Valve installs after the Besthead on the filtered water line, giving you a simple valve to open for the flush — a few litres to a bucket or drain, then close the valve and the filtered water is directed normally to the machine. Jim from Vancouver confirms: easy installation, no leaks, works as advertised. Highly Recommended for Size X and Above — Pressure ReliefThe Bestflush serves a second function that becomes more important with larger cartridges. BWT filter cartridges of size X, XL, and 2XL hold significantly more water volume than smaller sizes, and that water is held under mains pressure inside the housing. When changing a cartridge, releasing that pressure before unscrewing the housing is important — doing so without a flush valve can result in the housing ejecting under pressure when the cartridge is twisted off. The Bestflush Valve provides a controlled release point: open the valve to relieve pressure to a drain before changing the cartridge. For size S, V, and M cartridges the risk is lower, but for size X and above BWT strongly recommends the flush valve as part of the installation. Washers are included. Part of the BWT Installation Ecosystem at Coffee AddictsThe Bestflush Valve is the post-Besthead add-on for filter commissioning and pressure management. The core BWT inline installation consists of the BWT Besthead or Besthead FLEX filter head, the appropriate cartridge (Bestmax, Bestmax Premium, or Bestprotect), and optionally the BWT Adjustable Pressure Reducer upstream and the BWT Flowmeter for capacity tracking. The Bestflush Valve completes the downstream side of that setup. All BWT components are stocked at Coffee Addicts.
