Stainless steel unvented cylinders

McDonald Water Storage is synonymous with superior quality hot water cylinders and its STEELflow unvented cylinders are no exception.

Manufactured from premium grade duplex stainless steel ensuring superior corrosion resistance, STEELflow provides uncompromising efficiency and high quality standards, with high performance cylinders for those on a budget.

The new range is designed with the installer in mind, with the inclusion of a 90 degree elbow on the hot water draw off to reduce installation time and negate any damage caused by solder flux above the connection, in addition to the embossed label connections and compression fittings as standard.

STEELflow offers a comprehensive range of unvented cylinders from 60 – 300 litres in direct and indirect configurations, in addition to renewable solar thermal and heat pump solutions. Pre-plumb solutions are now available on direct, indirect and heat pump models.

Is the STEELflow not suitable for your installation? Click here to see our alternative unvented cylinder ranges;

  • POWERflow bespoke designed unvented cylinders with direct, indirect and solar thermal options
  • ECOflow bespoke designed unvented cylinders specifically designed for use with heat pumps

A comprehensive range of high performance stainless steel unvented cylinders for those on a budget, with fantastic features and benefits.

  • Premium grade duplex stainless steel providing superior performance
  • Direct and Indirect models 60 – 300 litres
  • Renewable options including Solar Direct, Solar Indirect and Heat Pump models 150 – 300 litres
  • Pre-plumb packages available on direct, indirect and heat pump models
  • 90 degree elbow on hot water draw off
  • Compression fittings as standard for ease of installation
  • Corrugated coil for maximum heat transfer
  • Optional titanium immersions available for commercial applications
  • External expansion for ease of servicing
  • 25 year guarantee

The STEELflow range is supplied with all the necessary components required to install the unit including;

Inlet Combination Control Set Pressure incorporating (Supplied)
• Pressure Reducing Valve set at 3 Bar
• Balanced Cold Feed set at 3 Bar
• Expansion Relief Valve set at 6 Bar
Temperature and Pressure Relief Valve
7 Bar/95 degrees C (Fitted)
Tundish (Supplied)
90 degree elbow on hot water draw off
3kW Immersion Heater – Primary Heat Source (Direct models – Fitted)
3kW Immersion Heater – Back Up Heat Source (Fitted)
Expansion Vessel (Supplied)
Dual Control and Overheat Thermostat (Indirect models – Supplied)
Single High Limit Thermostat (Solar and HP models – Supplied)
Two Port Motorised Zone Valve (Indirect models – Supplied)

Compression fittings are supplied fitted on all the STEELflow cylinders to provide a quicker installation process.

Technical Data

For a guide to sizing and dimensions see the brochure, give us a call on 01592 611123 or contact us online.

All of our STEELflow cylinders come with a 25 year guarantee and 2 years on components.

STEELflow: Quality guaranteed stainless steel unvented mains pressure system from McDonald Water Storage.

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