Electric marine toilet Sanimarin 31 for your boat: reduced height for narrow on-board bathrooms
The electric marine toilet Sanimarin 31 is the reduced-height electric toilet that SFA offers for a boat's bathroom. An integrated macerator pump grinds the sanitary wastewater and pumps it to the discharge. An integrated solenoid valve fills the bowl with clean water.
Size is its main strength. In fact, it stands 310 mm to the ceramic rim, weighs 17 kg and mounts on a raised step. That is why it suits narrow on-board bathrooms. SFA also says its compact size makes it easy to fit in small spaces.
Please note that the toilet and the control are sold separately. So the No control variant is the toilet only and needs one of SFA's controls (Comfort, Premium or Luxe). You then choose it separately on the Sanimarin controls page. There are also variants that already include the control. You also choose your boat's voltage, 12 V or 24 V.
Benefits of the electric marine toilet Sanimarin 31
- Reduced height: 310 mm to the ceramic rim and 340 mm with the seat, for on-board bathrooms with little room.
- Mounts on a raised step in the bathroom.
- Weighs 17 kg, against 23 kg for the Sanimarin 43: it is the lighter of the two.
- Removable soft-close seat with damped closing and a quick-release system.
- According to SFA, the whole range stands out for quiet operation. This model is rated at 52 dB(A) and comes with its own set of soundproofing foam.
- Stainless steel macerating turbine, with SFA's macerating technology and more than 60 years of experience, according to the manufacturer.
- According to SFA, it makes replacing manual-pump toilets easy.
- Low power consumption: for everyday use by 4 people, SFA puts it at less than 1% of energy consumption.
- According to SFA, the range stands out for its reliability and for saving water and electricity.
- Available in 12 V or 24 V, so you can choose according to your boat's voltage.
Is it compatible with your boat? On-board installation requirements
Before you buy, check that your boat's bathroom meets the requirements that SFA publishes. SFA gives no list of boat models or lengths, so compatibility comes down to these space, mounting and electrical figures. That is why the first table lists what to measure and work out for the electric marine toilet Sanimarin 31.
| Requirement | Data |
| Space (dimensions) | Seat width 370 mm, base width 250 mm, total depth 430 mm, base depth 240 mm, 317.5 mm from the back to the front of the base, height to the ceramic rim 310 mm and total height with the seat 340 mm (±10 mm tolerance on the ceramic dimensions) |
| Mounting type | On a raised step |
| Voltage | 12 V or 24 V direct current; you choose the variant that matches your boat's voltage |
| Electrical connection | Direct line from the boat's switch panel, dedicated to the toilet, with the polarity observed; a professional carries out the electrical installation |
| Current and fuse | 25 A at 12 V · 15 A at 24 V |
| Voltage drop | Maximum 5% (0.6 V at 12 V and 1.2 V at 24 V) |
As for the controls, you choose any of SFA's three separately, but there is one important limit: SFA allows the Premium push button on the bowl in every model except the Sanimarin 31. So on this model the Premium cannot go on the bowl. Instead, the manual asks you to fit it within easy reach of the bowl.
If you are unsure which of the three to pick, you will find a comparison further down.
Water, discharge and tank for the electric marine toilet Sanimarin 31
Besides the electrics, the water installation also decides compatibility. SFA asks for a vented loop, accessible through-hull valves and, on boats built from 2008 onwards, a black water tank, as the table details.
| Requirement | Data |
| Water supply | Pressurised on-board fresh water, using the integrated solenoid valve, or sea water with an optional auxiliary pump; minimum dynamic pressure of 1.7 bar and recommended pump flow rate of 11 L/min |
| Discharge | Up to 3 m vertically and 30 m horizontally; 38 mm or 25 mm outlet |
| Vented loop | Compulsory between the pump and the bowl, at least 50 cm above the waterline (not included) |
| Below the waterline | Rise at least 50 cm above it, with an anti-siphon valve at the highest point, then fall towards the 3-way valve |
| Through-hull valves | Accessible through-hull valves or, failing that, full-flow marine valves; the sea water intake must not be close to the black water through-hull fitting |
| Black water tank | According to SFA's manual, vessels built from 2008 onwards must have a black water tank; check the legislation on discharge into the sea |
So before choosing the variant, check three points on your boat: the voltage, the water pressure and the toilet's position relative to the waterline.
Cable cross-section by distance to the panel
Because the voltage drop must not exceed 5%, the cable cross-section has to increase with the distance to the panel. To help, SFA publishes the maximum length for each cross-section, at 12 V and at 24 V, as this table shows.
| Cable cross-section | Maximum length at 12 V | Maximum length at 24 V |
| 1.5 mm² | 1 m | 3.5 m |
| 2.5 mm² | 2 m | 6 m |
| 4 mm² | 3 m | 9.5 m |
| 6 mm² | 4.3 m | 14 m |
As you can see, at 24 V the same cable runs further than at 12 V. If your panel is far from the bathroom, work out the cross-section from this table before you buy the cable.
Technical specifications of the electric marine toilet Sanimarin 31
The next table gives the remaining official data for the electric marine toilet Sanimarin 31, as SFA publishes it.
| Field | Value |
| Brand and range | SFA, “Sanibroyeur marin SFA” range |
| Height | Reduced height, compact range |
| Noise level | 52 dB(A) |
| Weight | 17 kg |
| Motor power | 300 W at 12 V · 360 W at 24 V |
| Electrical class and protection | Class III · IPX4 |
| Non-return valve | Integrated, at the discharge outlet |
| Seat | Removable, with a soft-close mechanism (damped closing and quick-release system) |
| Made in | France |
| References | SN31-12V (12 V, EAN 3308815099545) · SN31-24V (24 V, EAN 3308815099552) |
With these figures, the electric marine toilet Sanimarin 31 weighs 17 kg and measures 52 dB(A). By contrast, the Sanimarin 43, at standard height, weighs 23 kg and drops to 46 dB(A).
Choose the control for your electric marine toilet Sanimarin 31
Since 2026 SFA has sold the toilet and the control system separately. One of the controls runs the toilet: a 2-position switch (Comfort), an electronic push button (Premium) or an electronic keypad (Luxe). The No control variant is the toilet only, so you choose the control separately. The table therefore sums up how each one is used and mounted.
| Control | How it works | Mounting details |
| Comfort | 2-position switch with no electronics: one position rinses (ADD WATER) and the other macerates and pumps out (PUMP OUT); you decide how long each runs | Ø 50 mm hole; it does not use the electronic control box and is wired with a terminal block |
| Premium | Electronic push button with 2 automatic cycles, bowl emptying (dry bowl) with a long press and an indicator light for a full black water tank | On this model it does not mount on the bowl; the manual asks for a spot that is easy to reach from it; it connects to SFA's electronic control box |
| Luxe white or black | Optical keypad with a white or black glass front, scratch-resistant and water-repellent, and a silicone cover; 2 automatic cycles, cycle programming, adjustable backlight, standby colour and beeps you can switch on; low consumption | 120 × 84 mm panel in an 88 × 48 mm cut-out, no more than 1.50 m from the current electronic control box, with which it is compatible |
| SFA electronic control box | Premium and Luxe connect to it; the Comfort does not need it | 105 × 78 × 43 mm, to fit in a dry, protected place |
Electronic control box for the Premium and Luxe controls
Important: the Premium and Luxe controls need SFA's electronic control box to work, while the Comfort does not use it. If you have any doubt about what your order includes, ask us before you buy.
For more detail, see the comparison of Comfort, Premium and Luxe controls.
How the electric marine toilet Sanimarin 31 works and how much power it uses
Here is what the electric marine toilet Sanimarin 31 does on each flush. When you operate the control, the solenoid valve fills the bowl with clean water. Then the stainless steel turbine macerates the contents and pushes them out through the discharge. As SFA states, its only job is to macerate and pump.
In addition, the water used per flush depends on the control. With Comfort you decide it. With Premium or Luxe it is adjustable from 1.6 to 3.4 L: the manual puts the NORMAL flush at 2 to 3.4 L and the ECO flush at 1.6 to 2.2 L.
To size your boat's battery, SFA gives the consumption in ampere-hours. It is per second of running with Comfort, and per cycle with Premium or Luxe.
| Situation | At 12 V | At 24 V |
| Comfort, per second of running | 0.007 Ah | 0.004 Ah |
| Premium or Luxe, ECO cycle | 0.056 Ah | 0.032 Ah |
| Premium or Luxe, NORMAL cycle | 0.105 Ah | 0.060 Ah |
For reference, SFA's website states that, for standard everyday use by 4 people, the Sanimarin's electricity use accounts for less than 1% of energy consumption.
Everyday use with each control
As a general rule, the toilet takes only faecal matter and toilet paper, whatever the control. Do not flush cotton wool, tampons, sanitary towels, condoms, hair, solvents or oils, because they damage the unit and void the warranty.
- Comfort: rinse to half a bowl, empty, then rinse again to leave water in the bottom.
- Premium: the NORMAL (large) flush is at the top and the ECO (small) one below. A long press on NORMAL empties the bowl. You can also programme the fill, with more or less water, and the Premium remembers it.
- Luxe: backlit NORMAL, ECO and empty keys, and a settings mode for the fill, the backlight, the colour and the beeps.
- In rough seas, empty the bowl: use the empty function on Premium and Luxe, or hold PUMP OUT on Comfort.
- Full tank: the Premium TANK indicator flashes red when 3 flushes remain. It stays solid red, with a lock-out, when the tank is full. Meanwhile, the Luxe keypad shows “Tank Full” and warns you with a red light and beeps.
- If you will be away for a long time or the power fails, turn off the water and disconnect the electricity.
That full-tank warning also depends on a high-level sensor in the black water tank, which is not supplied with the toilet.
Installing and fitting the electric marine toilet Sanimarin 31
If you are going to fit the electric marine toilet Sanimarin 31 on its raised step, follow this order. The steps summarise SFA's manual, so keep it to hand while you fit the toilet.
- Before you start, switch off the power and close the through-hull valves.
- Mark the outline of the base, position the brackets 15 mm away, drill and screw them in without tightening fully.
- Snap on the foam and fit the soundproofing foam supplied.
- Check the vented loop (50 cm or more above the waterline) and the accessible through-hull valves. Also, on boats built from 2008, check the black water tank.
- Have a professional run the direct electrical line from the panel, with the fuse and cable cross-section given in the tables.
- Fix the bowl to the brackets last, once all the connections are made, with a maximum torque of 1.5 N·m.
When you commission the toilet with Comfort, rinse for about 6 seconds with ADD WATER to half a bowl and add paper. Then press PUMP OUT for about 6 seconds and finish with ADD WATER for about 4 seconds. With Premium or Luxe, run a NORMAL cycle and then an ECO cycle with paper. Finally, always check for leaks.
What is in the box and the accessories you need
As the parts drawing in SFA's manual shows, the electric marine toilet Sanimarin 31 comes with the fitting parts below.
- 1 water connection pipe with an elbow fitting, for the bowl's water inlet
- 1 outlet sleeve
- 1 adapter, 25 mm
- 1 discharge elbow, 38 mm
- 3 clamps 32x55
- 3 floor-fixing brackets, with 3 washers, 3 wall plugs and 2 sets of 3 screws. One set fixes the brackets to the floor and the other fixes the bowl to them, with a maximum torque of 1.5 N·m
- Its own set of soundproofing foam for the Sanimarin 31 (floor foam and rear foam), which you must fit
However, you need to plan for other parts to complete the installation, because they are not supplied. If you need plumbing material, take a look at the water and sanitation collection.
- The control (Comfort, Premium or Luxe), except on the variants that include it
- The vented loop
- The black water tank high-level sensor, for the full-tank indicator on Premium and Luxe
- The auxiliary sea water pump (optional)
- The through-hull valves, the anti-siphon valve, the 3-way valve and the fuse, which the manual asks you to provide
Who is it for?
The electric marine toilet Sanimarin 31 is meant for anyone who wants an electric toilet on board and has a raised step to fit it on. SFA aims to offer the same comfort of use at sea as on land. These are the profiles that fit best, as long as you first check your boat's requirements:
- Owners of sailing boats with a small bathroom and little room to move.
- Owners of motor boats and leisure boats who are refitting the on-board toilet compartment.
- Sailors who want to swap a manual-pump toilet for an electric one, which SFA presents as an easy replacement.
- Anyone who puts weight first: at 17 kg, it is lighter than the Sanimarin 43, at 23 kg.
- Anyone fitting out a fishing boat with a compact on-board toilet compartment.
- Owners who prefer to choose their own control from Comfort, Premium and Luxe.
Maintenance, warranty and safety
As for maintenance, you clean the electric marine toilet Sanimarin 31 with standard sanitary products. If you lay up the boat for the winter, SFA says to run several cycles with clean water. Then empty the bowl and close the through-hull valves.
According to SFA's Spanish-language manual, the warranty is two years, or 3 years in Spain. During the first 6 months it also covers carriage, packaging and call-out costs. For safety, the same manual says that children over 8 and people with reduced capabilities should only use it with supervision.
To drain the shower, the washbasin or the sink too, there is the Sanimarin Pump Up grey water pump. It is another product in the range, sold separately.
Frequently asked questions
How does the electric marine toilet Sanimarin 31 work?
When you operate the control, a solenoid valve fills the bowl with clean water. The integrated macerator pump then grinds the wastewater and pumps it to the discharge, up to 3 m vertically and 30 m horizontally. In addition, according to SFA, the electric marine toilet Sanimarin 31 makes it easy to replace a manual-pump toilet.
What happens if I choose the No control variant?
Because the No control variant is the toilet only, you need one of SFA's controls to operate it (Comfort, Premium or Luxe). You choose it separately. You can add it from the controls page or simply choose a variant that already includes one.
Can I fit the Premium control on the bowl of the Sanimarin 31?
No. SFA allows the Premium push button on the bowl in every model except the Sanimarin 31. So on this model you must fit it away from the bowl but within easy reach of it, as the manual asks. The other two controls also need a different mounting: Comfort, a Ø 50 mm hole, and the Luxe keypad, an 88 × 48 mm cut-out.
Can I fit the electric marine toilet Sanimarin 31 below the waterline?
SFA covers that case with one condition. You must raise the pipe at least 50 cm above the waterline, fit an anti-siphon valve at the highest point and then run it down to the 3-way valve. The vented loop must also sit 50 cm or more above that line.
12 V or 24 V, and how much battery does it use?
Choose the variant that matches your boat's voltage. As for power, the motor is 300 W at 12 V and 360 W at 24 V. With Premium or Luxe, an ECO cycle uses 0.056 Ah at 12 V and 0.032 Ah at 24 V. A NORMAL one uses 0.105 Ah and 0.060 Ah. With Comfort, consumption is measured per second of running.
