Slimline Hot Water Cylinders

In addition to our extensive range of copper hot water cylinders, McDonald Water Storage offers a slimline version of any of our products for those situations where you need to minimise the space required for your hot water storage.

Depending on capacity and height available, our advanced manufacturing process can deliver hot water cylinders as small as 300mm finished diameter, the slimmest cylinders in the market.

Part of the reason we are able to manufacture to such tight diameters is down to the flexibility of copper.  This not only allows us to make such diameters easily, but also means we can put connections where you require them.  Boiler or Heat Pump Coils can also be manufactured to suit, ensuring there is enough heating surface to provide a quick recovery – something not achievable with other metals.

Compatible with renewable heat sources, our slimline range of cylinders also can come with an option of finishes: spray foam lagging or white cased.

And when it comes to quality, no compromises are made, with every Slimline cylinder manufactured to the same superior standards synonymous with the McDonald Water Storage name.

 Click here to see our full range of bespoke hot water solutions.

  • As little as 300mm diameter
  • Available in broad range of cylinder types
  • Boilers and heat pump coils manufactured to suit
  • Superior quality associated with McDonald Water Storage
  • Compatible with renewable heat sources
  • Option of fast heat models
Unit Dimensions

Dimensions excluding insulation 
Height x Diameter (mm)

90 Litre120 Litre150 Litre180 Litre210 Litre250 Litre300 Litre
300 wide
350 wide
400 wide
8001075135016201900N/A N/A
450 wide
700900110013001500 1800 2150

Please note:

For THERMflow combination models, you would need to add 250mm on to the height of each for the header tank

The table details shell sizes and will require insulation added which can be supplied up to 100mm thick


Our focus is very much on the manufacture of copper hot water cylinders and tanks. Copper provides fantastic benefits including;

  • Ability to kill 99% of bacteria including Ecoli and legionella
  • One of the most efficient conductors of heat
  • Significantly more flexible for manufacturing than other materials
  • Long lifespan due to its amazing resistance to corrosion
  • 100% recyclable


For further information see our brochure The Ultimate Supermetal or visit our Copper Facts page.

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