Marine Calorifiers

Marine Hot Water Cylinders

Marine Calorifiers - hot water cylinder heaters for boats

Pumped & unpumped hot water storage for marine vessels.

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Marine Calorifiers - Direct and Indirect unvented hot water cylinders

Hot water vessels manufactured to marine specification (also known as Calorifiers) are available in a particularly wide range of configurations in order to meet a variety of needs from the marine industry.

Vertical or Horizontal, single and twin coil Calorifiers

Marine Calorifiers can be manufactured to either a vertical or horizontal pattern and factory insulated. Marine cylinders can be made with single or twin heat exchangers to accommodate more than one heat source if available (e.g. engine, solid fuel, gas boiler, etc).

Custom and bespoke Calorifier design service

Marine Calorifiers can be manufactured with connections positioned as and where you want them affording amazing flexibility to the boat designer and simplicity to the fitter. This feature can be of particular importance when retrofitting, if space is at a premium or confined access makes positioning difficult.


Hot water cylinders built to cope with a harsh corrosive marine environment

In the aggressive salt water environment in which these vessels have to operate copper is arguably the best material from which to manufacture. The common belief that stainless steel doesn't rust is actually inaccurate. But the choice is yours. The price table below relates to Calorifiers made from copper. Stainless Steel marine Calorifiers are available by request.

  Calorifiers - Hot water cylinders for boats

Longer life Marine Calorifiers from superior build quality

Calorifiers specified on the table below are manufactured from a heavy gauge of copper to withstand a working pressure of up to 3 bar. This is suitable for most marine applications but even higher specification is available where higher operating pressures are required.

We can also offer you stainless steel Calorifiers if preferred. Simply call with your product specifications or requirements.

Water heating marine calorifiers for river craft

Hot water Calorifiers for work boats and trawlers

Calorifiers for hot water on residential, river boats and long boats

Cylinder Connections
Letter on Diagrams Connection type
A 1/2"male connection cold feed in
B 1/2" male connection hot draw off
C 1/2" male connection primary flow in
D 1/2" male connection primary return out
E 1/2" male connection expansion valve
F 2.1/4" female immersion connection
G 1/2" male connection auxilary primary flow
H 1/2" male connection auxilary primary return

Vertical pattern marine calorifier


Horizontal pattern marine calorifier


Hot water Calorifiers for all types of marine vessel


Marine Calorifiers Price List (Marine spec unvented hot water cylinders for boats)

Prices relate to horizontal or vertical pattern marine calorifiers.

  Capacity     GBP   GBP
Size (mm) Size (Inches) Litres Type   Inc VAT   Inc VAT
450 x 300 18 x 12 28 Indirect        
600 x 300 24 x 12 38 Indirect        
750 x 300 30 x 12 48 Indirect        
825 x 300 33 x 12 51 Indirect        
900 x 300 36 x 12 57 Indirect        
450 x 350 18 x 14 34 Indirect        
600 x 350 24 x 14 48 Indirect        
750 x 350 30 x 14 62 Indirect        
825 x 350 33 x 14 67 Indirect        
900 x 350 36 x 14 76 Indirect        
450 x 375 18 x 15 38 Indirect        
600 x 375 24 x 15 54 Indirect        
750 x 375 30 x 15 70 Indirect        
825 x 375 33 x 15 75 Indirect        
900 x 375 36 x 15 86 Indirect        
450 x 400 18 x 16 42 Indirect        
600 x 400 24 x 16 60 Indirect        
750 x 400 30 x 16 78 Indirect        
825 x 400 33 x 16 84 Indirect        
900 x 400 36 x 16 97 Indirect        
450 x 450 18 x 18 42 Indirect        
600 x 450 24 x 18 73 Indirect        
750 x 450 30 x 18 97 Indirect        
825 x 450 33 x 18 104 Indirect        
900 x 450 36 x 18 120 Indirect        


Extras and additional items

      GBP Inc VAT      

Expansion Relief Valve set at 3 bar            

Immersion Heater 1kW (230v)


Delivery Costs - are in addition to prices quoted and depend on your location in the world.


For most of mainland UK please see below. For international destinations please call for quotation.


Mainland UK delivery (Courier service)


For overseas delivery please call for quotation

Please don't hesitate to call if your specific requirement differs from those above


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