Under-Sink Water Filter & 3-Way Tap Guide

Water Flow Diagram:

Cold water supply under sink → Splits into two paths:

1. Path 1 (Normal): Goes directly to tap's hot/cold mixer (big lever)
2. Path 2 (Filtered): Goes to under-sink filter → Returns to tap's filtered water channel (small lever)

Both paths are completely hidden under the sink and inside the tap body. No visible tubes.

1. Aquaport Chrome Curved 3-Way Filtered Water Mixer

• WELS 4 Star rating (7L/min)
• Curved spout design
• Chrome finish
• Separate internal chambers for filtered vs unfiltered water

🔗 Link: Bunnings - Aquaport Curved 3-Way

2. Aquaport Chrome Square 3-Way Filtered Water Mixer

• WELS 4 Star rating (7L/min)
• Modern square neck design
• Chrome finish
• Supplies hot, cold, and filtered water

🔗 Link: Bunnings - Aquaport Square 3-Way

3. Stefani Elegance Chrome 3-Way Filter Mixer Tap

• Elegant curved design
• Chrome finish
• Connects to under-sink filtration system
• Dual-chamber design (filtered separate from mains)

🔗 Link: Bunnings - Stefani Elegance 3-Way

4. Stefani Modern Chrome 3-Way Filter Mixer Tap

• Contemporary design
• Chrome finish
• WELS rated

🔗 Link: Bunnings - Stefani Modern 3-Way

1. Measure Under-Sink Space

• Single filter housing: ~10cm wide × 30cm high
• Need clearance below to remove housing for filter changes
• Check for obstructions (garbage disposal, existing pipes)

2. Check Water Pressure

• Normal household pressure is fine (carbon filters handle standard pressure)
• If pressure is very high (>600 kPa), the included pressure limiting valve will protect the filter

3. Verify Existing Plumbing

• Locate cold water shut-off valve under sink
• Check that existing tap uses single hole (mixer tap style)
• Confirm hot and cold supply lines are 1/2" BSP (Australian standard)

Phase 1: Remove Old Tap (30 minutes)

1. Turn off both hot and cold water shut-off valves under sink (clockwise)
2. Turn on old tap to drain remaining pressure
3. Place bucket under sink
4. Disconnect hot and cold supply lines from tap (use basin wrench if tight)
5. Loosen mounting nut holding tap to sink (under sink)
6. Lift old tap out from above sink
7. Clean the sink hole area

Phase 2: Install Filter System (45 minutes)

1. Mount bracket:
   • Hold stainless steel bracket against cabinet wall/back panel
   • Mark drill holes with pencil
   • Drill pilot holes
   • Screw bracket securely to wall (use wall anchors if needed)
2. Hang filter housing:
   • Hang the single housing on bracket
   • Ensure it's secure and level
3. Connect inlet (from cold water):
   • Locate the cold water supply pipe
   • Install T-adapter or saddle valve to tap into cold line
   • Connect 1/4" tubing from T-adapter to filter inlet
   • Push tubing firmly into quick-connect fitting until it clicks
4. Connect outlet (to tap):
   • Run 1/4" tubing from filter outlet up through sink hole (alongside hot/cold lines)
   • Leave enough length to reach tap's filter connection (don't cut short!)

Phase 3: Install New 3-Way Mixer Tap (45 minutes)

1. Prepare tap:
   • Attach rubber gasket to base of tap (if provided)
   • Thread supply lines through tap base
2. Position tap:
   • From above sink, insert tap into sink hole
   • Ensure tap is oriented correctly (spout facing forward)
   • From below, thread mounting hardware onto tap
3. Connect hot water line:
   • Use adjustable wrench to connect hot supply line to tap's hot inlet
   • Wrap threads with plumber's tape (3-4 wraps clockwise)
   • Hand-tighten, then 1/4 turn with wrench
4. Connect cold water line:
   • Same process as hot water line
   • Connect to tap's cold inlet
5. Connect filter line:
   • Connect the 1/4" tubing from filter to tap's filtered water inlet
   • This is usually a push-fit connection (push firmly until it clicks)
   • Some taps may have a compression fitting (hand-tighten)
6. Secure tap:
   • Tighten mounting nut from below sink
   • Ensure tap is straight and secure
   • Don't over-tighten (can crack sink)

Phase 4: Start-Up & Testing (30 minutes)

1. Check all connections:
   • Visually inspect all fittings are tight
   • Ensure no tubing is kinked
2. Turn on water slowly:
   • Open cold water shut-off valve slowly (counter-clockwise)
   • Open hot water shut-off valve slowly
   • Listen for any hissing (indicates leak)
3. Check for leaks:
   • Inspect all connections under sink with torch
   • Run your hand along all tubing to feel for water
   • Check around tap base on sink surface
   • If leaks found, turn off water and re-tighten connection
4. Flush filter system:
   • Turn on the small lever (filtered water handle)
   • Let water run for 5-10 minutes into sink
   • Water will be black/grey at first - this is normal (carbon fines)
   • Continue until water runs completely clear
   • Discard this first batch (don't drink it)
5. Test both functions:
   • Test big lever: Hot/cold mixing should work normally
   • Test small lever: Filtered cold water should flow
   • Check there's no cross-contamination (filtered shouldn't be hot)
6. Final check:
   • Leave water running for 5 minutes
   • Check under sink one more time for any slow leaks
   • Tighten anything that's dripping

1. Turn off cold water supply valve under sink
2. Turn on filtered water lever to release pressure
3. Place bucket under filter housing
4. Use housing spanner to unscrew housing (turn counter-clockwise)
5. Housing will have water in it - pour into bucket
6. Remove old filter cartridge
7. Clean inside of housing with warm soapy water
8. Check o-ring for damage; lubricate with food-safe silicone grease
9. Insert new WC04 filter cartridge
10. Screw housing back on (hand-tight plus quarter turn)
11. Turn water supply back on
12. Check for leaks
13. Flush system for 5 minutes (water may be grey initially)