BWT Bestmax Premium Inline Filter Step-by-step Installation

by Steven Tucciarone 4 min read Updated: April 4, 2025
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This guide will walk you through the process of installing the BWT cartridge water filtration system. We'll cover connecting the filter head, pressure regulator, hoses, and optional accessories such as the Aquameter, which tracks filter life.

Technical Skills:

Basic plumbing skills recommended. Installation involves handling plastic fittings, brass connectors, and adjusting water pressure.

Tools Needed:

  • Adjustable wrench

  • Wire cutters or utility knife (optional for hose cutting)

  • Screwdriver or drill (for mounting bracket)

  • Teflon tape

Associated Parts:

Step-by-Step Installation Instructions

1. Identify and Prepare Components

Your BWT Premium Filter package includes:

  • Filter Head (with arrows indicating flow direction and an adjustment knob)

  • Pressure Regulator (with directional arrows)

  • Pressure Gauge (to measure output pressure)

  • Two Hoses (3/8" BSP to 3/8" compression fittings)

  • Mounting Bracket

Tip:
Label your filter cartridge with the installation date so you know when replacement is due (generally recommended annually).

2. Assemble the Filter Head and Pressure Regulator

  1. Determine Water Flow Direction:

    • Check the arrows on the filter head and pressure regulator; ensure they match the intended water flow toward your espresso machine.

  2. Install Pressure Regulator:

    • Place the pressure regulator on the inlet side of the filter head.

    • If necessary, reposition the pressure gauge plug using a 2.5 mm Allen wrench to ensure visibility of the gauge.

  3. Attach Pressure Gauge:

    • Wrap Teflon tape clockwise around the gauge threads (3–4 wraps).

    • Carefully screw the gauge into the regulator, taking care not to cross-thread (the housing threads are plastic).

    • Tighten gently until snug. Do not overtighten.

  4. Install Fittings on Pressure Regulator:

    • Insert provided flat rubber gaskets (O-rings) into the fittings.

    • Screw fittings into regulator inlet and outlet. Hand-tighten firmly, then slightly snug with wrench if necessary. Do not overtighten.

Caution:
Avoid cross-threading by ensuring fittings align properly and turn easily. If resistance is felt, back off and restart.

3. Connect Pressure Regulator to Filter Head

  • Use the supplied elbow fittings or optional straight fittings, depending on the filter size and installation space.

  • Insert fittings into the filter head and lock them by rotating the plastic cover from the "open" position to the "closed" position until it clicks securely.

4. Attach the Filter Cartridge

  • Screw the filter cartridge onto the filter head slowly, making sure it threads evenly to avoid cross-threading or damaging the threads.

5. Optional: Install the BWT Aquameter (Flow Meter)

  • If you're using the BWT Aquameter to monitor water usage, insert a gasket into the Aquameter fitting and secure it to the filter head outlet, aligning flow direction arrows correctly.

  • Lock in place with the supplied fitting cover.

Important:
Always confirm no protective plugs are inside the Aquameter by gently blowing air through it before installation.

6. Wall Mounting the Filter Assembly

  • Mount the supplied bracket securely onto a wall or cabinet, ideally attaching it to a stud. If mounting to drywall alone, use wall anchors.

  • Measure height carefully, leaving adequate space beneath the bracket for the filter cartridge and connections.

  • Slide the assembled filter head and cartridge onto the bracket, ensuring it locks securely in place.

7. Connect Water Supply Line to the Filter System

  • Attach the included BWT hose (3/8" BSP to 3/8" compression) to the inlet fitting of the pressure regulator. Tighten carefully.

  • Connect the opposite end of the hose to your household water supply line or shut-off valve.
    Note: No Teflon tape or additional sealants are needed as the hose includes an internal rubber gasket.

8. Connecting the Filtered Water Line to Your Espresso Machine

  1. Connect the second supplied BWT hose to the outlet fitting on the filter head assembly.

  2. Use the provided adapter or fitting compatible with your espresso machine's inlet:

    • ECM and most prosumer machines typically include a fitting that converts 3/8" compression to the machine-specific fitting.

    • For machines with different fittings, match accordingly.

  3. Secure the connection without overtightening. Ensure rubber gaskets are present and properly seated.

9. Alternative Plastic Tubing Connections (Optional)

  • Use optional insert-style fittings (available in 3/8" and 1/4" sizes) if using plastic tubing rather than braided hoses.

  • Secure plastic tubing directly into these fittings for easy, secure connections.

10. Initial Water Flush and Pressure Adjustment

  1. Flush the System:
    Upon installation, flush approximately 2 gallons of water through standard filters or 5 gallons for larger filters. This removes air and potential sediment.

  2. Adjust Water Pressure:

    • Push the regulator adjustment knob outward to unlock.

    • Rotate to set desired pressure (typically around 2 bar, but consult your espresso machine’s manual for exact specifications).

    • Run water through the filter to stabilize pressure reading.

    • Lock adjustment knob by pushing inward once set correctly.

Notice:
Always flush water after adjusting pressure to ensure accurate readings.

Safety and Troubleshooting Tips

  • Regularly inspect fittings and hoses for leaks.

  • Avoid overtightening fittings; rely on properly placed gaskets and moderate tightening for leak-free connections.

  • Cross-threaded components may leak; always thread fittings slowly and carefully.

Steven Tucciarone