MAREX 375 User manual

Our quality
Your safety and boat pleasure
You are now the owner of quality product from MAREX. Your boat is built by the
highest standards of safety and quality for your safety and pleasure.
The owner’s manual is written so that you as a boat owner can have the best
possibilities to get experienced with the boat and its functions. The owner’s manual
contains important information about handling, safety, systems, equipment
mounted or delivered with the boat. You will also find useful information about use
and maintenance.
It is recommended that you make yourself acquainted with the boats maneuvering
ability and properties before you start to use it, regardless of previous boating
experience. Your local dealer can assist you in finding an instructor or boating
school.
Please study the owner’s manual carefully before using the boat.
Producer:
MAREX Boats UAB
Eglių g. 1, Ilgakiemio km., Garliavos sen.,
LT-53288 Kauno r.,
Lithuania
Phone: [phone]
Fax: [phone]
E-mail: [email protected]t
MAREX
CONGRATULATES YOU
WITH YOUR NEW
Marex 375

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Contents
1.0 GENERAL INTRODUCTION...................................................................................4
1.1 INSTALLED EQUIPMENT ...............................................................................................................6
1.2 SYMBOLS USED IN THE OWNER’S MANUAL ..............................................................................6
1.3 CONSTRUCTION CATEGORIES....................................................................................................7
1.4 ABOUT THIS OWNER’S MANUAL..................................................................................................8
2.0 TECHNICAL DATA.................................................................................................9
2.1 GENERAL TECHNICAL DATA........................................................................................................9
2.2 HULL ................................................................................................................................................9
2.3 WINDSCREEN...............................................................................................................................11
2.4 ENGINE..........................................................................................................................................11
2.5 ELECTRIC SYSTEM......................................................................................................................11
2.6 CAPACITIES..................................................................................................................................12
3.0 SAFETY ................................................................................................................13
3.1 GENERAL......................................................................................................................................13
3.2 FIRE ...............................................................................................................................................14
3.2.1 PORTABLE FIRE EXTINGUISHER .......................................................................................14
3.2.2 AUTOMATIC FIRE EXTINGUISHER .....................................................................................15
3.2.3 FIRE ALARM ..........................................................................................................................17
3.3 COOKER AND OVEN....................................................................................................................17
3.3.1 GAS INSTALLATION AND LEAKAGE TEST INSTRUCTION..............................................20
3.4 ELECTRIC SYSTEM......................................................................................................................21
3.5 BATTERIES ...................................................................................................................................21
3.6 ENGINE ROOM .............................................................................................................................22
3.7 FUEL TANK....................................................................................................................................22
3.8 THROUGH HULL LEADS - UNDER THE WATERLINE................................................................23
3.8.1 CLOSING VALVE - SEAWATER INLET FOR THE TOILET SYSTEM..................................23
3.8.2 CLOSING VALVE - BLACKWATER OUTLET........................................................................24
3.8.3 CLOSING VALVE - SEAWATER INLET FOR ENGINE COOLING.......................................25
3.9 STABILITY AND BUOYANCY .......................................................................................................25
3.10 SAFETY EQUIPMENT.................................................................................................................26
3.11 EMERGENCY EXITS...................................................................................................................27
3.12 EMERGENCY STEERING...........................................................................................................27
4.0 DRAWINGS AND TECHNICAL DESCRIPTIONS OFTHE BOAT ........................28
4.1 ARRANGEMENT AND EXTERIOR DRAWINGS..........................................................................28
4.2 TECHNICAL SYSTEMS.................................................................................................................28

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4.2.1 DRAWINGS OF THE TECHNICAL SYSTEMS......................................................................28
4.2.2 PICTURES AND DESCRIPTION OF INSTALLED COMPONENTS......................................29
4.3 FUEL SYSTEM ..............................................................................................................................29
4.4 DRAINING SYSTEM......................................................................................................................31
4.5 LENSING SYSTEM........................................................................................................................32
4.5.1 MANUAL LENSING SYSTEM ................................................................................................32
4.5.2 AUTOMATIC LENSING SYSTEM..........................................................................................32
4.6 FRESH WATER SYSTEM.............................................................................................................34
4.7 SEPTIC SYSTEM/BLACK WATER SYSTEM................................................................................36
4.8 ELECTRIC SYSTEM......................................................................................................................39
4.9 EXHAUST SYSTEM ......................................................................................................................41
4.10 VENTILATION SYSTEM FOR THE ENGINE..............................................................................42
4.11 FIRE EXTINGUISHING SYSTEM................................................................................................42
5.0 OPERATION .........................................................................................................44
5.1 STARTING OF THE ENGINE........................................................................................................44
5.2 BATTERIES (LEAD ACCUMULATORS).......................................................................................45
5.3 FUSE PANEL & CONNECTION SCHEMES .................................................................................47
5.4 MAIN SWITCH PANEL ..................................................................................................................47
5.5 WINDSCREEN WIPERS ...............................................................................................................48
5.6 DASHBOARD INSTRUMENTS INSTALLATION ACCESS...........................................................48
5.7 ELECTRIC SYSTEM......................................................................................................................49
5.8 SEPTIC SYSTEM ..........................................................................................................................52
5.9 OPERATING OTHER EQUIPMENT..............................................................................................55
5.9.1 COOKER AND OVEN ............................................................................................................55
5.9.2 DEFROSTER..........................................................................................................................55
5.9.3 DIESEL HEATER....................................................................................................................56
5.10 MANOEUVRING OF THE BOAT.................................................................................................57
5.11 HINTS AND ADVICES.................................................................................................................60
5.11.1 LIFTING AND STORAGE IN A “CRADLE”...........................................................................60
5.11.2 BOAT TRANSPORT.............................................................................................................61
5.11.3 BOAT MOORING..................................................................................................................61
5.11.4 BOAT ANCHORING.............................................................................................................62
5.11.5 TOWING AND BEING TOWED............................................................................................62
6.0 PERIODIC MAINTENANCE..................................................................................63
6.1 MAINTENANCE OF THE HULL.....................................................................................................63
6.1.1 BEFORE PLACING THE BOAT ON WATER.........................................................................63
6.1.2 BEFORE WINTER STORAGE...............................................................................................63

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6.1.3 NORMAL MAINTENANCE .....................................................................................................64
6.2 MAINTENANCE OF THE TEAK DECK .........................................................................................64
6.3 MAINTENANCE OF THE ENGINE AND THE DRIVE...................................................................64
6.4 MAINTENANCE OF THE STEERING SYSTEM ...........................................................................64
6.5 MAINTENANCE AND CONTROLLING OF THE ELECTRIC SYSTEM........................................65
6.6 MAINTENANCE OF THE GAS SYSTEM ......................................................................................66
6.7 MAINTENANCE OF THE FUEL SYSTEM.....................................................................................67
6.8 MAINTENANCE OF THE LENSING SYSTEM..............................................................................68
6.9 MAINTENANCE OF THE FIRE EXTINGUISHERS.......................................................................69
6.10 MAINTENANCE OF THE FRESH WATER TANKS ....................................................................69
6.11 MAINTENANCE OF THE FENDER LIST ....................................................................................69
7.0 PREPARING FOR THE SEASON.........................................................................70
7.1 GENERAL PREPARATION...........................................................................................................70
7.2 PREPARING THE ENGINE AND THE DRIVE..............................................................................70
7.3 PREPARING THE STEERING ......................................................................................................70
7.4 OTHER EQUIPMENT ....................................................................................................................71
7.5 REMOVING RUST/CORROSION..................................................................................................71
8.0 WINTER STORAGE PREPARATION...................................................................72
8.1 BATTERIES ...................................................................................................................................72
8.2 HULL ..............................................................................................................................................72
8.3 STEERING SYSTEM.....................................................................................................................72
8.4 SEPTIC SYSTEM ..........................................................................................................................73
8.5 FRESHWATER SYSTEM..............................................................................................................73
8.6 ENGINE AND DRIVE.....................................................................................................................73
9.0 ENVIRONMENTAL ISSUES.................................................................................74
10.0 POSITIONS OF THROUGH HULL AND DECK FITTINGS ................................75
10.1 STARBOARD SIDE .....................................................................................................................75
10.2 PORT SIDE..................................................................................................................................76
10.3 TOP VIEW - HULL BOTTOM.......................................................................................................77
10.4 TOP VIEW - DECK ......................................................................................................................77
11.0 OVERVIEW .........................................................................................................78
ANNEX 1: A CHECKLIST OF ALL NECESSARY ACTIONS BEFORE USE ............80
ANNEX 2: A CHECKLIST OF ALL NECESSARY ACTIONS AFTER THE WINTER
STORAGE...................................................................................................................81

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1.0 GENERAL INTRODUCTION
This manual has been compiled to help you to operate your craft with safety and
pleasure. It is not a course on boating safety or seamanship. If this is your first boat, or
if you are changing to a type of boat you are not familiar with, for your own comfort and
safety, please ensure that you obtain handling and operating experience before
“assuming command” of the boat.
Ensure that the anticipated wind and sea conditions will correspond to the design
category of your boat, and that you and your crew are able to handle the boat in these
conditions. Even when your boat is categorized for them, the sea and wind conditions
corresponding to the design categories A, B and C range from severe storm conditions
for category A, to strong conditions for the top of category C, open to the hazards of a
freak wave or gust. These are therefore dangerous conditions, where only a competent,
fit and trained crew using a well maintained boat can satisfactorily operate.
This owner's manual is not a fully detailed maintenance or trouble-shooting guide. In the
case of difficulty, refer to the boat builder or his representative.
Always use trained and competent people for maintenance, fixing or modifications.
Modifications that may affect the safety characteristics of the boat shall be assessed,
executed and documented by competent people. The boat builder cannot be held
responsible for modifications that have not been approved.
Always maintain your boat properly and make allowance for the deterioration that will
occur in time and as a result of heavy use or misuse of the boat.
Any boat, no matter how strong it may be, can be severely damaged if not used properly.
This is not compatible with safe boating. Always adjust the speed and direction of the
boat to sea conditions.
The boat should have appropriate safety equipment (lifejackets, harness, etc.) on board
according to the type of boat, weather conditions, etc. This equipment is mandatory in
some countries. The crew should be familiar with the use of all safety equipment and
emergency manoeuvring (man overboard recovery, towing, etc.), sailing schools and
clubs regularly organize drill sessions.
All persons should wear a suitable buoyancy aid (life jacket/personal floatation device)
when on deck. Note that, in some countries, it is a legal requirement to wear a buoyancy
aid that complies with their national regulations at all times.
The owner’s manual is written according to the following standard:
EN-ISO-10240:2004.

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Type: Marex 375
Construction category: B
Approval: EC TYPE EXAMINATION BY DET IMSI (INTERNATIONAL
MARINE CERTIFICATION INSTITUTE)
Certificate number:_______________
See copy enclosed in divider number 5.
The boat’s CIN number (Craft Identification Number) is engraved aft of the boat, under
the fender-list, on the starboard side.
Picture 1: The boat’s CIN number location
PLEASE KEEP THIS MANUAL IN A SECURE PLACE, AND HAND IT OVER TO
THE NEW OWNER IF YOU SELL THE BOAT.

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1.1 INSTALLED EQUIPMENT
Divider number 4 contains a list of installed equipment in your boat.
1.2 SYMBOLS USED IN THE OWNER’S MANUAL
DANGER:
The “Danger” warnings in the owner’s manual or in the installed component MUST
be followed to avoid personal injury or serious material damage.
WARNING:
The warnings must be followed to avoid damage on boat or on equipment.
CAUTION:
This should be remembered to avoid damage on persons or equipment.
 DESCRIPTION:
This is the description of location of the equipment or component.
INSTRUCTION MANUAL:
Read the separate instruction manual/user manual for this equipment. This is
placed in the “User bag” enclosed in the boat.

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1.3 CONSTRUCTION CATEGORIES
EU-directive 94/25/EC defines the following construction categories:
A. OCEAN: This craft is designed for extended voyages where conditions may exceed
wind force 8 (Beaufort scale) and significant wave heights of 4 m and above but
excluding abnormal conditions, and vessels largely self-sufficient.
B. OFFSHORE: This craft is designed to operate in winds up to Beaufort force 8
and the associated wave heights (significant wave height up to 4 m). Such
conditions may be encountered on offshore voyages of sufficient length, or on
coastal waters when unsheltered from the wind and waves for several dozens of
nautical miles. These conditions may also be experienced on inland seas of
sufficient size for the wave height to be generated.
C. INSHORE: This craft is designed to operate in winds up to Beaufort force 6 and the
associated wave heights (significant wave height up to 2 m). Such conditions may be
encountered in exposed inland waters, in estuaries, and in coastal waters in moderate
weather conditions.
D. SHELTERED WATERS: This craft is designed for voyages on sheltered coastal
waters, small bays, small lakes, rivers and canals when conditions up to, and including,
wind force 4 and significant wave heights up to, and including, 0,3 m may be
experienced, with occasional waves of 0,5 m maximum height, for example from passing
vessels.
Boats in each category must be designed and constructed to withstand these
parameters in respect of stability, buoyancy, and other relevant essential requirements,
and to have good handling characteristics.
CAUTION:
THE ACTUAL USE OF THE BOAT IS ON OWN RISK. READ ALL THE WARNINGS
IN THE OWNER’S MANUAL.

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1.4 ABOUT THIS OWNER’S MANUAL
✓This owner’s manual is a part of the documentation that follows the boat.
✓Included in the boat is a “user bag”that contains the owner’s manual and
separate instructions.
Picture 2: The user bag
✓This “user bag” is considered a part of the boat and must be included in the boat
for future owners.
✓Marex is continuously developing the quality of its products. This owner’s manual
contains information updated at the time of the print of this book and may
therefore deviate from your boat. Please contact Marex or your local dealer if
questions regarding the owner manual appear.
✓This owner’s manual is adjusted to a standard equipped boat.
✓Many Marex boats are custom made. Equipment that is not of significant
importance to the safety or stability of the boat is not incorporated in this owner’s
manual.

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2.0 TECHNICAL DATA
Part of the information is given on the builder’s plate fixed on the craft. A full
explanation of this information is given in the relevant sections of this manual.
2.1 GENERAL TECHNICAL DATA
Boat type: Marex 375
Construction category: B
2.2 HULL
Type
Measurement
Unit
Length over all, including bowsprit and platform (LOA)
11,99
m
Length of hull (Lh)
11,90
m
Length hull waterline (LWL)
9,68
m*
Transport height without lantern mast and mounted
extra equipment (Transport height excluding the rudder
and propeller)
3.49
m*
Transport height without lantern mast and mounted
extra equipment (Transport height including the rudder,
propeller and propeller protector)
3.83
m
Total height from bottom to top lantern mast, including
flagpole
4.3
m*
Height from the waterline (Sailing height) with lantern
mast, including flagpole
3.71
m*
Height from the waterline (Sailing height) with lantern
mast, excluding flagpole
3.71
m*
Height from the hulls keel to the top of the lantern mast,
including top lantern
4.3
m
Height of the mounted and removable lantern mast
0.81
m
Marex cradle height
0.10
m
Beam excluding fender list BOA
3.45
m
Beam including fender list BOA
3.49
m
Beam of the boat waterline BWL
3.075
m
Displacement of empty boat (twin engine)
7400
kg *
Maximum recommended load**
2400
kg
Maximum allowed displacement***
9800
kg
- m*/ kg* standard boat and weight with twin engine installation (2 x Volvo D4)
- ** Maximum recommended load includes the weight of all persons onboard, all
provisions and personal effects, any equipment not included in the light craft mass,
cargo (if any) and all consumable liquids (water, fuel, etc.).
- *** see section 2.5 Capacities for detailed loading condition.

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Figure 1: Main dimensions

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2.3 WINDSCREEN
Defects allowed:
1. Scratches up to 30 mm in length, no more than 1 pcs on one glass.
2. Damages smaller than 0.5mm, no more than 3 pcs on one glass.
3. Damages smaller than 2mm in diameter, within 30 mm of the edge. No more than
3pcs on one glass.
2.4 ENGINE
Engine type:
Twin Marine Diesel, 2 x 221 kW (300hp) 370hp max.
Propulsion type:
Twin Z drive
2.5 ELECTRIC SYSTEM
Voltage:
12V DC & 230V AC
Starter battery:
2 x 100 Ah
Optional: AGM Starter battery 2x 95 Ah
Service batteries:
4 X 95 Ah

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2.6 CAPACITIES
Fuel tank:
700 litres* (All of its capacity may not be
usable according to trim and loading and
20% reserve should be kept.)
Water tank:
350 litres* - 2 x 175 litres (All of its
capacity may not be usable according to
trim and loading.)
Septic tank:
150 litres*
Lens pump –manual:
Engine room:
Front cabins:
23.6 L/min
23.6 L/min
Lens pump –electric:
Engine room:
Front cabins (optional):
54.25 L/min
54.25 L/min
Max load incl. 10 persons (adults),
full tanks and luggage:
2400 kg
Max load incl. 10 persons (adults)
and luggage (as shown on
the producer plate):
1000 kg
Max recommended number
of persons:
10 persons (adults)
* Total weight of liquids (fuel, water, grey & septic tank), when all permanently installed tanks are full, is 1400 kg.
WARNING:
Do not exceed the maximum recommended number of persons. Regardless of the
number of persons on board, the total weight of persons and equipment must
never exceed the maximum recommended load. Always use the seats/seating
spaces provided.
WARNING:
When loading the craft, never exceed the maximum recommended load. Always
load the craft carefully and distribute loads appropriately to maintain design trim
(approximately level). Avoid placing heavy weights high up.

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3.0 SAFETY
We summarize the important information for safety aboard. A great deal of the
information will be repeated later in the owner’s manual, but Marex signify the
importance for you as a customer and user of the boat that this information must be
easy accessible in a stressed situation.
What is described here should be carefully studied by the user!
3.1 GENERAL
WARNING:
Never:
✓let objects block the emergency exits (doors and hatches).
✓let objects hinder access to the fuel stop valve, lens pumps and electrical
switches.
✓let objects hinder access to fire extinguishers.
✓use gas lights.
✓change any of the boats technical systems –especially the gas fuel and electrical
systems.
✓fill the fuel tank while the engine is running or while the cooker or heater is in use.
✓smoke when handling fuel.
✓use the rails to pull anything after the boat.
✓use the rails as mooring.
✓place fenders at the exhaust outlets for heater and cooker.
Always:
✓inspect the whole boat, particularly the engine room for leakages before every
start-up of the engine.
✓have cabin doors closed during sailing. The weight of the doors can make the
doors slam. Also close all port lights and windows during rough weather
conditions or while planning.
✓hold lensing pump free from impurities.
✓check for leakage of the fuel system.
✓check the fuel level.

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3.2 FIRE
DANGER:
INSTRUCTION MANUAL
➢Portable fire extinguisher (2 kg, type ABE class II - powder apparatus) is
located at the step near the helm position.
➢The engine room has an automatic fire extinguisher system with auto
discharge and auto stop of the engine. This extinguisher has an indicator
located by the dashboard.
WARNING:
•Do not mount curtains or other fabrics over or close to any cooker or open flame
sources. It is prohibited to store flammable material in the engine room! If non-
flammable material is kept in the engine room it must not block access or risk
contact with hot engine parts.
•Do not store equipment containing petrol (outboard engines, tanks, petrol
generators, etc.) in compartments that are not designed for this purpose.
When fire gets out of control, you have to:
➢take on the emergency vests.
➢send emergency signals by radio or chart plotter, signal lights or telephone.
➢evacuate the boat.
3.2.1 PORTABLE FIRE EXTINGUISHER
INSTRUCTION MANUAL
See the separate user manual in the “user bag”. Read the instructions of the apparatus
and be prepared for an emergency.
Picture 3: Location of the portable fire extinguisher (Sitting Group)

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WARNING:
▪Do not lift or transport the extinguisher holding the sensor valve.
▪Do not drop the extinguisher.
▪Keep the extinguisher out of reach from the children.
▪After a discharge –REPLACE the extinguisher with a new one.
INSTRUCTION MANUAL
All fire extinguishers must be controlled one time per year by qualified personnel.
The user/owner is responsible for:
▪That the extinguisher is controlled by qualified personnel at recommended times.
▪That the extinguisher is replaced with working equipment.
▪Inform the passengers about:
✓the location and use of the fire extinguisher.
✓the location of the emergency exits.
▪Assure that fire extinguisher is easy accessible.
3.2.2 AUTOMATIC FIRE EXTINGUISHER
INSTRUCTION MANUAL
Read the manual for Sea-Fire, enclosed in the “user bag”.
Boats with engines larger than 120 kW (163 Hp), are equipped with a permanent fire
extinguisher in the engine room.
Picture 4: Automatic fire extinguishing system (1) in the
Engine room with visible volume level indicator (2)
1
2

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The fire extinguisher in the engine room automatically discharges by temperatures over
74o C. Indicator by the helmsman’s position informs if the extinguisher has been
discharged. When automatic discharge of the content happens, the engine stops
automatically!
Picture 5: Fire extinguisher indicator
When the ignition is on, the lamp indicator will light as long as the system is ready to be
discharged. After a discharge the lamp will no longer light.
Picture 6: The fire extinguisher lamp indicator
at the dashboard (1)
CAUTION
Your boat has an automatic fire extinguishing system in the engine room that uses
FM200 as an active component.
1

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PROCEDURE WHEN AUTOMATIC DISCHARGE HAPPENS:
➢When automatic discharge of the content happens, you have to turn off the main
switches.
➢Then evacuate the cabins.
➢Let the automatic extinguisher in the engine room work for several minutes.
➢Grab the manual fire extinguisher and release the safety pin.
➢After discharge always ventilate before entering the engine room. When
you open the engine hatches, have the manual extinguisher ready and be
alert.
➢Control the engine room for remaining fire.
DANGER:
The engine room has a non-removable installed system. The content of the
extinguisher can cause serious respiration problems or even death.
3.2.3 FIRE ALARM
Marex is one of few producers that mount a fire alarm as standard equipment. We
prioritize your safety and have mounted several fire alarms, on the front cabin ceiling,
hallway ceiling and in the cockpit near the main sliding door.
3.3 COOKER AND OVEN
Standard equipment includes a gas cooker.
INSTRUCTION MANUAL
▪Read user manuals and installation instructions.
DANGER:
Remember that the cooker uses gas and oxygen, to burn!
WARNING:
▪The cooker must not be used as a heating oven.
▪Never leave the boat with gas devices in use.
▪Never start the cooker without checking the system.
CAUTION
▪Avoid contact of materials with naked flames and other hot areas.
▪Do not use detergents containing ammoniac.

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➢The gas bottle islocated inthe bathing platform bench storage. The compartment
where the gas bottle is kept is drained out under the bathing ladder cover.
Picture 7: Gas bottle storage with the pressure reduction valve (1)
The pressure reduction valve must never come in contact with saltwater; when it
does, it will start to corrode. If any corrosion is seen it must be changed before
you use the gas system. The pressure reduction valve must be controlled often
and should be replaced every year.
The gas closing valve is located on aft deck in the small bench.
Picture 8: Gas closing valve for cooker and oven (1)
1
1
1

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➢If the gas cooker is installed:
✓Close the closing valves to the cooker and the valve in the compartment
on the bathing platform when the cooker is not in use.
✓Close the valves before changing the gas bottles.
✓Close the valves immediately in an emergency.
✓Make sure that the valves are closed before opening the safety cap on the
bottle.
•Do not block the access to any components of the gas system.
•Keep the valves for empty gas bottles closed and disconnected. Keep hatches
closed and all plugs in place. Store the spare gas bottle in ventilated rooms or in
a gas tight container with certified ventilation.
•Never use the gas boxes for storing of other equipment.
•Do not use the gas system if the boat is not in balance.
WARNING:
Fuel burning devices with open flame consume oxygen in the cabin and release
products of combustion into the boat. Ventilation is required when gas appliances
are in use. Open designated venting openings while gas appliances are in use.
Never obstruct ventilation openings and ensure that gas appliances are operating
correctly.