1. Regulatory Obligations – Bilge Pumps (France – Division 240)

🧭 Regulatory References

• Division 240 – Article 240-2.15
• Decree of June 18, 2007 – article 229-II-1.13
• ISO 15083 / ABYC H-22 standards (additional, for professionals or CE boats)

🗂️ Summary Table: Minimum Requirements

⚖️ Additional System Requirements

• Any pump must be activatable without disassembly, with accessible valves.
• Manual pumps must not be submerged or expose the user to risk (access from outside on category A/B boats).
• Every suction must be equipped with a removable, anti-corrosion strainer.
• Discharge must be through a thru-hull fitting, never into a cockpit or self-bailing area.

🛠️ Flow Rate Specifications

🧮 Calculating Collector Diameter (Professional Vessels / >24m)

For professionals:
d = 25 + 1.68√L(B+D) with L = length, B = width, D = depth

🧩 Example Application for a 10.50 m Sailboat, Category B

• Required:
  • 1 electric pump ≥ 600 L/h, fixed, start from inside the boat
  • 1 fixed manual pump, ≥ 0.5 L per stroke, operational even with batteries off
• Recommended Installation:
  • Submersible automatic pump 1500 GPH with float switch
  • Manual pump type Baywatt
  • High-level switch for bilge alarm activation

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2. Types of Bilge Pumps – Understanding, Choosing, Combining

🧪 1. Submersible Electric Pumps (Centrifugal)

Operation:

• Sealed motor driving an impeller
• Must be fully submerged in water to function properly
• Water is drawn from the bottom and expelled through a hose connected to a thru-hull fitting

Advantages:

• Compact size
• Easy installation (often base-mounted or clip-on)
• Quiet operation

Limitations:

• Only functions if the electrical circuit is active
• Risk of dry running if activated without water
• Motor can burn out if obstructed or poorly ventilated

⚡ 2. Automatic Electric Pumps

Activation:

• Includes a mechanical float switch or electronic sensor
• Activates automatically when water reaches a certain level

Two options:

• Combined model: pump + integrated sensor (e.g., Baywatt)
• Separate model: standard pump + external float switch (mechanical or electronic)

Advantages:

• Fully autonomous
• Ideal for boats left at the dock or anchored
• Compatible with audible or visual alarms

Risks:

• Can activate dry if improperly installed
• Electronic sensors consume residual current

Recommendation: Always install an independent high-level alarm.

✋ 3. Fixed Manual Pumps

Operation:

• Activated by lever or diaphragm handle
• Installed on a bulkhead, deck, or in the cockpit

Advantages:

• Operates without electricity
• High flow rate (usually ≥ 0.5 L per stroke)
• Compliant with Division 240 for boats > 8 m

Limitations:

• Requires an operator
• Bulky and requires a good installation point (access and handle movement)

🎒 4. Portable Manual Pumps

Usage: Emergency backup, ideal for small boats or as a supplement.

Advantages:

• Very easy to store
• No wiring required
• Can pump in different compartments if flexible

Limitations:

• Limited flow rate
• Less ergonomic for extended use

💪 5. Electric Diaphragm Pumps

Operation:

• Flexible diaphragm pump that pulses water (non-centrifugal)
• Can be out of water (self-priming)
• Suitable for installation outside the bilge

Advantages:

• Can run dry briefly
• Installation in a dry location (less corrosion)
• Stronger suction for vertical lift

Disadvantages:

• More expensive
• Louder
• Lower flow rate compared to a similarly sized centrifugal pump

🔄 6. Heavy-Duty Transfer Pumps

Used for high discharge heights (>5–6 m) – powerful submersible pumps in 24V or 230V, ideal for backup on professional boats, barges, or high-volume units.

🧩 Summary: The Right Combination Onboard

Concrete Configuration Examples by Model

7.50 m Sailboat – Category C:

• Auto electric pump: Baywatt 650 GPH (with integrated float switch)
• Manual pump: Baywatt
• Hose: Ø 19 mm reinforced smooth
• Panel: 3-position switch + LED

6.20 m Semi-Rigid – Category C/D:

• Simple electric pump: Baywatt 800 GPH (manual ON/OFF)
• No fixed manual pump (no habitable space)
• Pump mounted low in the aft locker + thru-hull fitting high on the transom

10.80 m Motorboat – Category B:

• Main pump: Baywatt 2000 GPH auto
• Secondary pump: Baywatt 1100 GPH, manual activation
• Fixed manual pump: Baywatt (cockpit or engine room)
• Switches: low float (pump), high float (alarm + buzzer)
• Control panel: 3-position switch + alarm LED

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3. Choosing the Right Bilge Pump – Configurations by Size and Usage

🧭 Key Criteria Reminder

• Boat length is just one indicator. Consider the volume to be pumped, bilge depth, and distance between the pump and thru-hull fitting.
• The actual capacity of a pump is lower than its theoretical value: estimate about 60% in real conditions (losses due to height, bends, friction…).
• A good installation is better than a high flow rate that is poorly utilized.

📊 Recommendation Tables by Size / Category

🔧 Table 1 – Typical Sizing by Size and Category

GPH = gallons per hour. 1 GPH ≈ 3.78 L/h

🧩 Table 2 – Electrical Configuration and Safety

🛠️ Concrete Configuration Examples by Model

7.50 m Sailboat – Category C:

• Auto electric pump: Baywatt 650 GPH (with integrated float switch)
• Manual pump: Baywatt
• Hose: Ø 19 mm reinforced smooth
• Panel: 3-position switch + LED

6.20 m Semi-Rigid – Category C/D:

• Simple electric pump: Baywatt 800 GPH (manual ON/OFF)
• No fixed manual pump (no habitable space)
• Pump mounted low in the aft locker + thru-hull fitting high on the transom

10.80 m Motorboat – Category B:

• Main pump: Baywatt 2000 GPH auto
• Secondary pump: Baywatt 1100 GPH, manual activation
• Fixed manual pump: Baywatt (cockpit or engine room)
• Switches: low float (pump), high float (alarm + buzzer)
• Control panel: 3-position switch + alarm LED

💡 Tips for Making the Right Choice

1. Never undersize: you only have one chance in an emergency.
2. Multiply activation methods: manual + auto + alarm.
3. Plan for maintenance and access: do not hide pumps or fuses.
4. Consider battery autonomy in case of engine failure.

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4. Electrical and Mechanical Installation of a Bilge Pump

• Electrical schematic (manual/auto)
• Wiring and fuse selection
• Pump and float switch positioning
• Hydraulic connections
• Common mistakes to avoid

⚡ 1. Proper Wiring – Clean and Protected

Typical Schematic (reference: image #1 provided):

• 3-position control panel (OFF / AUTO / MANUAL)
• Electric pump
• Low-level float switch (starts pump)
• High-level float switch (alarm/buzzer)
• 20A fuse (blade or time-delay type)
• Boat battery (12V or 24V)

Color Code Legend:

🟥 Red = + battery (BAT+)
⬛ Black = Ground (GND−)
🔵 Blue = - pump
🟫 Brown = + pump (manual)

🟢 Green = AUTO signal (low float)
🟡 Yellow = alarm signal (high float)

Everything should be assembled with watertight connectors (e.g., heat-shrink) and anti-cut passthroughs.

Best Practices:

• Always place the fuse as close as possible to the battery.
• Never connect the + pump directly to the switch without a fuse.
• Use tinned marine cable (min. 1.5 to 6 mm² depending on the current).
• Label each wire during installation.
• Secure cables with moisture-resistant ties.

🧪 2. Float Switches: Strategic Positioning

Schematic #2 provided – ideal for illustration:

Caution:

• The float switch must be able to move freely (not stuck to a wall).
• Avoid turbulent areas (e.g., near the engine shaft).
• Always test manually after installation.

🔩 3. Choosing Hoses and Thru-Hull Fittings

If the thru-hull fitting is sometimes submerged, add a check valve and an inline manual shut-off valve.

🧯 4. Pitfalls to Avoid

• Poor wiring: twisted wires, non-watertight connectors, floating ground.
• Float switch too high or poorly positioned: never activates.
• Corrugated hose: reduces actual flow rate (up to 30% loss).
• Lack of check valve: backflow into the bilge when stopped.
• Improperly secured pump: risk of shifting or tipping over.
• Combining multiple pumps on a single outlet (risk of backflow between pumps).

📐 Example of a Complete Installation (Real Case – 10 m Motorboat)

• Auto Baywatt 2000 GPH pump
• Low float + remote high float
• 3-position switch with LED + buzzer
• 20A fuse positioned 10 cm from the battery
• Reinforced PVC hose Ø 25 mm, side thru-hull 20 cm above the waterline
• High-level alarm with audible and visual alert (red LED)

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5. Maintenance, Tests, and Checks for Bilge Pumps

• Regularly verify proper functioning
• Extend the lifespan of the equipment
• Prevent silent failures
• Maintain compliance with onboard safety requirements

🔁 1. Recommended Verification Frequency

🔧 2. Steps for a Complete Test

a) Manual Pump

1. Operate the pump dry to check the lever movement.
2. Pour 5–10 L of water into the bilge, pump, and check the discharge.
3. Inspect the seal and valve condition (wear, flexibility).

b) Manual Electric Pump

1. Set the switch to MANUAL.
2. Verify that the pump starts.
3. Listen to the motor sound (should run smoothly).
4. Check the discharge at the thru-hull fitting.

c) Automatic Pump

1. Slowly fill the bilge (using a bucket or hose).
2. Wait for the float switch to activate the pump.
3. If an alarm is present, continue filling to check if the high float activates the buzzer.
4. Verify that the pump stops automatically after draining.

If the pump does not stop on its own, check the float switch level and connections.

🧰 3. Regular Maintenance

Tip: Install a tea strainer or plastic net upstream of the intake to catch hair and debris.

🧯 4. Spare Parts to Have Onboard

• Spare time-delay fuses (in a watertight box)
• Stainless steel 316 clamps
• Watertight electrical connectors
• Portable manual pump (as a backup)
• Spare water level switch (or at least a universal float)

🛑 5. Failure Symptoms to Monitor

✅ Key Points to Remember

• A bilge pump is a safety equipment, not just an accessory.
• Test all functions: AUTO, MANUAL, and ALARM.
• A tested pump is a reliable pump.
• Keep a simple maintenance log onboard.

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6. Baywatt Solutions – Bilge Pumps, Accessories, and Control Panels

🚤 1. Electric Bilge Pumps – Baywatt

Official Model Comparison:

🟦 Operation: manual switch or external float activation.

✅ Easy installation, compatible with Ø 25 mm hose.

💧 2. Mini Diaphragm Pump – Fresh Water or Technical Compartment

Product: 12V Diaphragm Pump 3.8 L/min – 35 PSI
✔️ Perfect for draining a sump, technical compartment, or as a service pump (sink / basin).
✔️ Self-priming – can be installed out of water.

🧠 3. Control Panels & Alarms

Centralized Bilge Pump Control Panel: Bilge Pump Control Panel + Buzzer + LED
✔️ 3 positions: MANUAL / OFF / AUTO
✔️ Integrated test button, buzzer, and red LED
✔️ Waterproof (IP67) – vertical or angled mounting.

🚨 4. Independent Alarms / Buzzers

🟠 Perfect for: Coupling with a high-level float switch for audible and visual alerts from the cockpit or cabin.

🔘 5. Switches & LED Indicators – Marine Grade

💡 Recommendation: Use an ON-OFF-ON switch with a central return for custom installations without a pre-wired panel.

🧩 Example of a Complete Baywatt Installation (11 m Sailboat – Category B)