Flexiheat UKHigh recovery cylinder range – 140 to 2,000 Litres
High recovery or high gain cylinders from 200 to 2,000 litres – unvented cylinders or vented option from Flexiheat UK
A high recovery cylinder is an increasingly popular model in domestic hot water heating systems. These advanced hot water production and storage solutions are revolutionising how users meet their hot water demands, offering many advantages: maximum heat transfer, high efficiency, reliability, and cost-effectiveness compared to standard-size coil cylinders, i.e., standard cylinders.
This type of hot water cylinder can also be referred to as a high gain cylinder, rapid recovery hot water cylinder, or quick recovery hot water cylinder as they benefit from an extra-large surface area heating coil for maximum heat transfer, ensuring heat-up times are reduced and high volumes of heated domestic hot water can be produced.
A fast recovery cylinder with a high recovery coil allows heating engineers to install smaller cylinders as a space-saving option without losing water heating performance with fast heat up and recovery times.
You can purchase this product range as vented cylinders or as unvented cylinders, with an expansion vessel kit accommodating the water expansion.
Understanding a quick recovery hot water cylinder
A high or rapid recovery cylinder is a type of hot water storage tank designed to heat water quickly and efficiently. They are an indirect hot water storage cylinder, which can be powered by system boilers (gas boiler, electric boiler or oil boiler) or by a low- or high-temperature heat pump. They are available as an indirect fast recovery unvented cylinder or as an indirect vented high recovery hot water cylinder, so we have the full range to cover every installation requirement.
Maximum heat transfer
The heat exchanger coil of our quick recovery single coil cylinder range are the largest on the UK market. We blow away our competition on this aspect, as this feature ensures that far more domestic water is in contact with the surface area of the heating coil exchanger, dramatically enhancing the transmission of heat between the primary and secondary water and, thus, the high recovery rate of the cylinder.
Unlike traditional cylinders that may take hours to heat a full tank of water, quick recovery cylinders can replenish hot water supplies rapidly, making them ideal for locations or applications with high-demand periods.
The “recovery” in high recovery refers to the speed at which the cylinder can heat cold water to the desired temperature after hot water has been drawn from the system. This rapid recovery is achieved through a large coil heat exchanger and improved insulation.
This applies when the boiler’s kW rating is lower than the fast recovery cylinder’s kW output. The boiler, not the cylinder, will then affect the reheat time. However, the cylinder’s higher kW rating will help lower return temperatures to the boiler and increase efficiency when a condensing boiler is installed.
Key Benefits of High Recovery Cylinders
- Rapid Hot Water Replenishment: The primary advantage of high recovery cylinders is their ability to quickly heat water. This ensures a consistent supply of hot water, even during peak demand periods.
- Energy Efficiency: These cylinders, despite their high-performance capabilities, feature an energy-efficient design. They incorporate features like enhanced insulation to minimise heat loss and maximise energy consumption and reduce running costs.
- Space Savings: High recovery cylinders can often provide the same hot water output as a larger traditional cylinder while occupying less space. This makes them especially valuable in commercial settings where space is limited.
- Cost-Effectiveness: Economical, as less stored hot water is required, and the long-term operational costs are often lower due to improved energy efficiency and reduced maintenance needs.
- Because a lot of hot water is not heated and squandered when it is not needed. Additionally, these fast recovery hot water cylinders significantly decrease boiler cycling, which results in significant fuel bill savings and increased client satisfaction.
- Versatility: These systems can be tailored to meet specific commercial needs, with options for different fuel types (gas or oil boilers, electric, or hybrid systems) and various capacities.
- Reliability: Built for heavy use, our quick recovery hot water cylinders are designed to withstand constant use, reducing downtime and maintenance requirements.
- Improved Hygiene: Our high recovery hot water cylinder range includes features to prevent the growth of bacteria, ensuring a safer hot water supply.
- Immersion heater top-up or backup – Various immersion heater kW outputs can be fitted to either operate as a top-up or backup water heater should you lose the primary heating source during the installation.
- Suitable for heat pumps – both air source heat pumps, ground source heat pumps – use higher-temperature heat pumps, i.e., R290 air source heat pumps, which have higher temperatures for the best recovery rates / better recovery times.
- With options of the standard glass lined cylinder shell (suitable for hard water areas) or corrosion resistant stainless steel domestic hot water storage tanks (stainless must be used in soft water areas – predominantly found in Scotland, Wales, and certain regions of Northern Ireland and England, especially in the northern and western areas).
- Suitable for use with heat pumps or system boilers – electric, gas or oil boilers – to suit your preferred fuel source. Our even solar thermal systems to power these quick recovery coil cylinders.
- Our 200 to 500 litre duplex stainless steel high-gain cylinders are fitted with high level 70mm thermal-injected insulation and have an ErP rating of “A” with a global warming potential of less than 5 and an ozone depletion potential (ODP) of 0.
- The 800 to 2,000 litre high-gain cylinders are fitted with high level 100mm polyester fibre insulation, which is an ecologic, non-allergic, non-toxic, 100% recyclable material and is resistant to mould, humidity, rodents, insects and parasites with an Ozone Depletion Potential (ODP) of 0.
Heat pumps
Our large coil indirect hot water cylinders, or rapid recovery hot water cylinders, are also well-suited for heat pump systems, which need a large coil and an electrical immersion heater to raise the stored water temperature to 60°C to kill Legionella. This limitation arises because heat pump systems typically operate at a lower flow temperature, around 55°C.
Duplex stainless steel range from 140 to 1,500 litres
Our duplex stainless steel, high-performance, quick recovery hot water cylinder models are rated for 6 bar and a maximum temperature of 90°C. The large-surface-area coil is manufactured from 316 stainless steel and is rated for 10 bar and a maximum of 120°C for the primary heat source and has low pressure drops. They all come with one immersion heater port as standard.
Double extra-large coil indirect quick recovery cylinder DHW performance outputs from Flexiheat UK
The 140 to 500 litre models have a very high efficiency ErP ‘A’ rating.
Please note – the heat source or boiler size must be 5% to 7% higher than the kW output of these quick recovery cylinders, as no heat exchanger is 100% heat transfer efficient. You will achieve maximum heat transfer and kW output the higher the flow temperature to the coil and, thus, the volume of hot water produced.
Rapid recovery hot water cylinder heating performance data
The high gain cylinder, or quick recovery cylinder, water heating performance is directly related to three factors.
- The water temperature feeding the coil heat exchanger in the hot water tank is.
- The volume of this heating water that flows to the coil of the indirect water heater.
- The water temperature rise – i.e., from 10°C cold water to 60°C.
Domestic hot water heating performance from 10°C to 60°C
Recovery rates, kW outputs and flow rate details for our fast recovery indirect cylinders.
Domestic hot water heating performance from 10°C to 45°C
Recovery rates, kW outputs and flow rates detail for our high gain indirect cylinders.
Download the brochure for the 200 to 500 Litre low pressure drop coil high gain cylinders, showing weight, dimensions in mm, outlets, etc., this range has no inspection / clean out port here
ELC “HF” 200,300 and 500 litre quick recovery cylinders with low pressure drop coil brochure
Download the brochure for the glass lined / enamelled 200 to 2,000 litre high recovery hot water cylinder models, showing weight, dimensions in mm, outlets, etc. – these units have an inspection / clean out port as standard here –
Please note – Glass lined / enamelled tanks have sacrificial anodes – Anodes typically last 3–5 years, depending on water quality (hard water or water softeners accelerate corrosion). So, there is a maintenance issue with these tanks.
Sacrificial anodes are rods of a more reactive metal (like zinc, magnesium, or aluminium) that corrode (oxidise) instead of the metal structure to which they’re attached, protecting it from galvanic corrosion in water, and are common in enamelled (glass-lined) steel tanks.
Through an electrochemical process, the anode attracts corrosive particles and minerals, breaking down itself rather than the tank.
They work by sacrificing themselves, slowly wearing away to provide a protective electrical current, and must be replaced when depleted to continue protecting the glass lining of the water heaters.
or
Our stainless steel quick recovery cylinders option (must be used in soft water areas) can also be used in hard water areas – they do not require sacrificial anodes; thus, when used in hard water areas, you have none of the maintenance / replacement requirements of the anode like you do with glass-lined / enamelled units. They are the best of the best, as they say.
Vented or unvented high-gain cylinders
We can provide the models in a vented or unvented water heating configuration – we just add an expansion vessel kit, pressure and temperature safety valve, etc., for unvented water heater requirements.
Commercial water heating users
The primary users of high recovery cylinders are commercial entities with high hot water demands, such as:
- Hotels, restaurants, and caravan or camping shower room blocks.
- Hospitals and healthcare facilities
- Industrial kitchens and food processing plants
- Launderettes and commercial laundry facilities
- Sports centres and gyms
These businesses benefit from the consistent hot water supply and energy efficiency that quick recovery hot water cylinders offer.
Insulation of our quick recovery hot water cylinders
All models have low heat loss insulation fitted as standard, which complies with the ErP regulations with low global warming potential and ozone depletion potential.
Hard water
A lot of the United Kingdom has hard water conditions (please refer to the below map). You should fit a suitable scale inhibitor system or water softener to be positioned on the pipe connections before the indirect fast recovery hot water cylinder to maintain suitable water quality and prevent limescale on the coil and the immersion heater of the calorifiers.
Water hardness levels vary across the country, but approximately 60% of the United Kingdom is within hard water areas.
A 1 mm layer of limescale can reduce heating efficiency by about 7%, and a 1.6 mm layer can reduce it by 12%.
Water hardness map of the UK and Ireland – a lot of the country is hard to very hard in terms of calcium levels, which affects the potential for scale.
Contact us for your quick recovery hot water cylinder requirements
For more details, check stock, lead time, delivery, price, or to order our reliable and high quality high recovery cylinders, as we sell our high performance and competitively priced high gain cylinders directly. Please call our sales service team at 01202 822221 or use our site email contact form.
Flexiheat UK
Flexiheat UK