Copper Unvented Hot Water Cylinder

The POWERflow, copper unvented hot water cylinder is built to deliver superior mains pressure simultaneously for showers, sinks and wash hand basins. It has revolutionised new build and refurbishment schemes, bringing greater flexibility, increased cost effectiveness and much improved performance.

While the pressure in traditional open vented hot water systems was provided by the head of water from the cold feed cistern, with the POWERflow it comes direct from the cold mains supply.

One of the leading generation of energy efficient unvented hot water cylinders with mains pressure in the UK, the POWERflow unvented hot water cylinder offers:

  • Solar and Heat Pump Units Available
  • Copper – superior performance
  • No tanks in the attic
  • Proven Reliability – 25 year guarantee
  • Reduced maintenance
  • Very easy to install
  • No anode
  • Produced by the UK’s most experienced cylinder manufacturer
  • Slimline Unvented Hot Water Cylinders Available

For a guide to sizing and dimensions simply visit our sizing page. In addition to our standard sizes we offer a bespoke service creating tailored units – to discuss your options just contact us on 01592 611123 or contact us online.

POWERflow Guarantee

All of our POWERflow unvented hot water cylinders come with a 25 year guarantee.

POWERflow: the leading energy efficient unvented hot water cylinder from Mcdonald Water Storage available across the UK and Ireland.

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.