THERMFlow mains pressure hot water system

Our THERMflow thermal store works at the heart of your heating and hot water system to supply the central heating system in addition to mains pressure hot water. Our thermal store approach can incorporate multiple energy sources to heat the home as well as meet hot water demand to achieve improved efficiencies and cost savings.

All models of the THERMflow thermal store provide excellent heat retention and lower heat loss with the new improved white cased finish and high density foam insulation, with the option to increase to either 75mm or 100mm.

With our unique design and manufacturing solution, we can offer significant cost savings both during installation and ongoing running costs. In addition to the standard configurations, every thermal store can be supplied with custom connections, positioned exactly where you need them to minimise pipework and installation costs.

With a total focus on high performance and reliability, our THERMflow thermal storage cylinder is designed to:

  • heat up quicker than competitors thanks to an increase in copper coil size
  • achieve a consistently high water temperature due to a combination of our unique design and copper’s increased efficiency
  • virtually eliminate any queries or issues faced by clients after installation
  • is a suitable replacement for Albion Mainsflow and Range Flowmax thermal storage systems

Manufactured from premium grade copper, our THERMflow mains pressure hot water system delivers unrivalled performance thanks, in part, to copper’s superior thermal transfer properties and natural bacteria killing capabilities.

However one of our key advantages is the extra long copper coil which we incorporate into every THERMflow cylinder. This ensures the water heats up quicker than other thermal storage system, achieves a higher temperature, improves efficiency and reduces ongoing costs.

Is the THERMflow not suitable for your installation? Click here to see our alternative thermal stores within the range;

  • MULTIflow cased design
  • MULTIflow+ cylinder design
  • CUBEflow rectangular tanks providing space saving solution
  • Delivering Mains Pressure Water
  • Easy to install – does not require G3 certification
  • Requires no annual maintenance
  • Specialists in like for like replacements – even for other manufacturers
  • All our thermal stores are manufactured from copper – kills bacteria such as legionella
  • Built in scald protection
  • Rectangular and Slimline Units Available

Our THERMflow Thermal Store works by reversing the function of the Primary (Heating) and Secondary (Domestic) waters. The Primary water is stored in the cylinder and heated by either a boiler or immersion heater.

When heated by a boiler the water can also be pumped round the radiators to provide space heating. The Secondary water comes directly from the mains and passes through a specially designed heat exchanger which draws heat from the Thermal Store. This water then passes through a thermostatic mixing valve which blends it to the correct temperature before it reaches the taps. Additional heat sources such as solar, solid fuel, heat pumps etc can also be utilised very effectively with a THERMflow .

Compatible with the latest Renewable Heat Incentive Scheme, our Thermal Store Mains Pressure Hot Water System integrates seamlessly with multiple fuel installations.

Our THERMflow hot water storage system is suitable for multi-fuel installations including:

  • solar thermal
  • heat pumps
  • solid fuel, such as, wood stoves
  • wind
  • electric
  • boilers

The THERMflow Thermal Storage System can enable the core energy sources of electricity, gas and oil to be supplemented, or indeed substituted, with more sustainable fuels, such as solar, heat pumps, solid fuel and wind.

The Thermal Store cylinder diagram below shows how multiple fuel sources can be incorporated into the thermal storage system. 

Click here to find out more about the sizing and specifications of the THERMflow Thermal Storage Hot Water Cylinders.

As you can see from the schematics below, the THERMflow  hot water storage system can also be used for a wide range of applications including the Combination type Electric Model which features an immersion, the combination type sealed system boiler model which features a system coil for the heating if its locate below the radiators, an immersion and a separate feed and expansion tank.

The final diagram shows a Combination Type Boiler Model which draws upon solar thermal technology, gas or oil, solid fuel, and an immersion.

Check out out interactive thermal storage with solid fuel, solar and boiler connections to provide an insight into what can be achieved. To discuss your project call us now on 01592 611123

If you are looking to squeeze your Thermal Store cylinder into a tight space, we also offer Slimline versions of our THERMflow.

Typically measuring, an industry leading, 450mm in diameter including the insulation, these slimmer models are manufactured to the same standards and designs as our THERMflow units.

However thanks to our flexible approach to manufacturing and our use of copper, we can manufacture hot water cylinders as small as 300mm shell, plus the required foam lagging.

We can even place the connections in the best location for the installation, making further savings on installation time and costs.

Our flexible manufacturing expertise also enables us to design and deliver rectangular thermal stores to suit specific requirements and specifications. 

Whether you are looking for a replacement Elson tank or maximising the capacity of your thermal store within a given area, our CUBEflow thermal stores are the perfect solution. Click here to see the full range of Rectangular Thermal Stores.

Our technical sales team have produced a number of handy tips and guides regarding thermal storage solutions in response to regular questions being asked by our clients. Check them out below

Is the THERMflow thermal store vented or pressurised?

The THERMflow is an open vented cylinder therefore not pressurised. When the water held inside the store heats up, it will expand, however the expansion is accommodated in the feed and expansion tank located either on top of the unit or remotely higher in the property if being used for an open vented heating system

Do I need to have the THERMflow serviced annually like a gas boiler or unvented cylinder?

As the THERMflow thermal store is open vented, it does not require an annual safety check or service.

The mains pressure hot water from the THERMflow is delivered via the internal coil and the temperature is controlled by the blending valve, preventing any risk of scalding.

As the unvented cylinder is a pressurised cylinder, there are essential annual safety checks to be carried out to ensure the safety of the product.

Can I use the THERMflow thermal store for central heating?

Yes, the THERMflow can provide heat to the central heating system. This can either be an open vented system, circulating the water from the cylinder round the central heating system or s sealed heating system via in internal heat exchanger.

Is the THERMflow a suitable replacement for Albion Mainsflow products?

Yes, the THERMflow provides a direct replacement solution for Albion Mainsflow and also the Range Flowmax products.

Are the THERMflow products bespoke designed?

The THERMflow is available with standard tapping configurations, however we appreciate these layouts do not suit all applications.

Therefore all THERMflow products can be bespoke designed to suit the installation requirements, whether it is a slimline model due to space restrictions, larger coils for faster reheat, increased tappings for additional heat sources orsimply moving tappings to reduce installation time and costs.

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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