Marine calorifiers and industrial water heaters perform the same basic function. Both store and heat water for use across a building, facility or vessel.
However, a marine installation introduces a different set of engineering constraints.
Space is often limited. Access routes can be restrictive. Equipment must remain secure while the vessel moves. Connections may also need to suit an established onboard services layout.
As a result, a standard industrial water heater cannot always be transferred directly into a marine application.
| Consideration | Industrial Water Heater | Marine Calorifier |
|---|---|---|
| Installation environment | Stable plant room | Moving vessel |
| Typical orientation | Usually vertical | Vertical or horizontal |
| Mounting | Floor-standing | Base plate or custom supports |
| Installation access | Planned plant-room access | Restricted hatches and machinery spaces |
| Connection positions | Often standardised | Frequently customised |
| Dimensions | Standard proportions are often suitable | Height and diameter may need adapting |
| Maintenance access | More surrounding space is usually available | Service clearances must be planned carefully |
Restricted space and installation access
Capacity is only one part of marine water heater specification.
Two cylinders can hold the same volume while having very different proportions. One may be tall and narrow, while another may be shorter with a larger diameter.
This matters because a marine calorifier may need to pass through:
- Restricted access hatches
- Narrow corridors
- Machinery-space doorways
- Existing pipework
- Areas with limited headroom
- Compartments containing fixed equipment
The route into the vessel can therefore be just as important as the final installation space.
Specifiers should confirm hatch sizes, doorway widths, turning space and lifting restrictions before approving the cylinder dimensions.
Where standard proportions will not work, a bespoke marine calorifier can provide the required capacity within a more suitable height and diameter.
Mounting and vessel movement
An industrial water heater normally stands vertically on a stable plant-room floor.
A marine calorifier operates in a moving environment. Its mounting arrangement must account for vibration, vessel movement and the available fixing points.
Depending on the application, this may require:
- A welded base plate
- Purpose-designed mounting brackets
- Additional fixing points
- Reinforced supports
- Horizontal installation
- A non-standard support arrangement
The intended orientation must be established before manufacture.
Immersion heaters, internal coils and connections must all be positioned to suit the final installation. A cylinder designed for vertical use should not simply be installed horizontally without confirming that its internal arrangement is suitable.
Custom connections and service access
Industrial water heaters often use established connection positions because the surrounding pipework can be routed to suit the cylinder.
Marine projects frequently work the other way around.
The calorifier may need to fit around:
- Existing pipe routes
- Bulkheads
- Machinery
- Electrical equipment
- Maintenance zones
- Restricted side access
Custom connection positions can reduce pipework changes and simplify installation.
These may include non-standard positions for:
- Cold-water inlets
- Hot-water outlets
- Primary coil connections
- Secondary returns
- Immersion heaters
- Temperature sensors
- Drain points
- Safety equipment
Top-mounted fittings may also be useful where access around the sides of the cylinder is limited.
Maintenance clearance should be considered at the same stage. It is not enough for the calorifier to fit into the space. Engineers must also be able to remove immersion heaters, inspect controls and access valves throughout the vessel’s service life.
What should marine specifiers provide?
The initial specification should include:
- Required capacity
- Maximum working pressure
- Design temperature
- Intended orientation
- Maximum height and diameter
- Installation access dimensions
- Mounting requirements
- Heat-source temperature and flow
- Recovery requirements
- Immersion heater requirements
- Connection sizes and positions
- Relevant project requirements
For replacement projects, drawings and photographs of the existing unit and surrounding space can also help identify potential constraints.
Bespoke marine water heating from EXCELSIOR
EXCELSIOR manufactures stainless steel marine water heaters for commercial and specialist applications.
Marine units can be designed around restricted installation spaces, onboard heat sources and project-specific connection requirements.
Available options include:
- Capacities from 50 to 3,000 litres
- Bespoke height and diameter combinations
- Custom connection positions
- Direct and indirect heating
- Application-specific internal coils
- Base plates for secure installation
- Optional top-mounted fittings
- Horizontal and vertical configurations
- Stainless steel construction
A marine calorifier should not be selected by capacity alone.
The correct unit must fit into the vessel, connect to the available services and deliver the required hot water performance. It must also remain secure and accessible throughout its working life.
Contact the EXCELSIOR team to discuss a new marine water heating project or the replacement of an existing marine calorifier.
