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Warmflow's range of KIWA approved unvented cylinders ensure the largest hot water volumes, shortest heat-up times and lowest possible heat losses. From the large coil-in-coil heat exchangers to the high performance foam insulation, Warmflow's cylinders are the market leaders.

Mains Pressure Hot Water cylinders

Because the cylinders work at mains pressure, they provide outstanding hot water flow rates, far exceeding those experienced
with a combi boiler or traditional vented cylinder. As a result, baths fill quickly and showers are invigorating. And, because we supply an inlet control group with a balanced cold water connection, all the hot and cold taps in the house operate at the same pressure, so blending valves work at their best to ensure consistent comfortable hot water temperatures.

Environmental investment

The cylinders have a thicker layer of high quality polyurethane insulation meaning the range has amongst the lowest fully certified heat loss levels currently on the market, saving precious fuel and reducing carbon dioxide emissions. The insulation is also CFC/HCFC-free, has a zero Ozone Depletion Potential (ODP) and a Global Warming Potential of only 2. Due to the large surface areas of our coil-in-coil heat exchangers it is also possible for a condensing boiler to work in condensing mode for longer, and cycle less frequently when heating the hot water, thereby helping to further reduce fuel use and emissions.

Quality Design with built-in reliability

Rather than using thin wall corrugate flexible tube for their heat exchanger coils, they use rigid coil-in-coil exchangers formed from high quality stainless steel pipe, as they believe this provides greater stability, quality and durability. Because the coils are
formed from long lengths of pipe, they have large surface areas for heat transfer - the performance figures speak for themselves.

All models are manufactured from high quality Duplex stainless steel, a strong and light weight material ideal for pressurised cylinders, and are fully 3rd party tested, approved and certified. Employing patented design features*, innovative manufacturing techniques and industry best practice their cylinders have a 'crevice free' construction which, combined with the use of Duplex stainless steel, ensures corrosion resistance and a long service life. This, and the fact that they test every cylinder to in excess of the maximum pressure it will experience in operation, means they can confidently offer a 25 year guarantee+. So peace of mind comes as standard.

Key Features of the cylinders

  • Available in Indirect, Twin Coil, Triple Coil,
  • Direct and Eco Direct models
  • Volumes from 90 to 300 litres
  • Duplex stainless steel construction
  • 316 stainless fittings
  • High performance rigid coils
  • White leathergrain casing
  • 22mm pipe connections throughout

Triple Coil Twin coil Eco Direct Indirect Direct