Indirect calorifier in domestic hot water (DHW) installations.The Stainless Steel Indirect (SSI) range from Adveco is designed to serve as an

Posts

Hybrid Hot Water Systems for Lower Carbon

The drive to bring greater sustainability into commercial and public sector buildings has never been more urgent, yet the consistent need for heat, in particular, to meet hot water demands cannot be avoided. Reducing carbon from what is typically classed as a business-critical service, especially in the wake of COVID and the drive to enhance hygiene, is certainly achievable with hybrid hot water systems. However, technical challenges remain, and inherent cost implications need to be overcome when reducing a building’s energy demands. This is especially true of small to medium scale operations, typified by offices, GP surgeries, cafes and restaurants and smaller schools.

Achieving 60°C in a calorifier is a basic requirement for a commercial domestic hot water (DHW) system. But achieving this through a direct electric-only immersion system is costly, even when compared to current surging gas prices. For this reason, air source heat pumps (ASHPs) would appear to be a perfect alternative, supplying low carbon heat to the building, and it is clear why the Government has championed the technology as a key ingredient in forging a path to net zero.

Heat Pumps and Commercial Hot Water

However, with ASHPs offering greater efficiencies in low-temperature systems, the high-temperature demands of commercial applications prove especially challenging. High working flow temperature from the ASHP would need to be at least 65°C, but to achieve this requires greater compression of the refrigerant, requiring more electrical input which results in a lower Coefficient of Performance (COP), in other words, efficiency is lost. As well as struggling to achieve these temperatures year-round in the UK, the very low drop in COP effectively counteracts the value gained from deploying ASHP.

A working flow of 50°C is however attainable all year round from an ASHP. If employed as a source for a preheat, the heat pump can be used to offset the direct electric costs of top-up after heat. Therefore, commercial new builds and refurbishment where gas is no longer being specified, are defaulting to this hybrid option.

Nonetheless, there remain a series of challenges. Aside from the additional system complexity, when connected to a traditional indirect water heater the lower flow temperatures generated by an ASHP lead to around a 50% drop in energy transfer compared to traditional gas-fired boilers. The size of the coil in the indirect calorifier can additionally limit heat transfer and affect system capacity. But for all-electric hybrid systems by far the most common problem comes from how the calorifier’s coil and the immersion interact.

An efficient electric hybrid hot water approach depends on harmoniously balancing these different system elements to ensure that they do not work against each other. If the coil and immersion are too closely situated, they become impossible to accurately control resulting in a steep drop in system efficiency. To avoid these issues, a hybrid hot water system would, up until now, be best served by employing a plate heat exchanger (PHE) with low-temperature hot water (LTHW) and domestic hot water (DHW) buffers alongside the ASHP. That of course further exacerbates the system complexity, space requirements and capital costs. For smaller to mid-scale hot water applications those capital costs can be hard to justify, forcing them, if possible, to be written off against sustainability gains.

Hybrid Hot Water Systems Designed for Commercial Buildings

In response, Adveco has been working in close cooperation with its customers to address the core challenges of delivering hybrid all-electric hot water heating into light commercial-scale building projects using ASHP technology. Evolving from bespoke system builds to award-winning packaged plant room applications, it became apparent that there is a growing demand for lower carbon pre-sized systems that are easy to specify, straightforward to install, resilient and cost-effective. This work has led to the creation of Adveco’s FUSION FPH-S range of all-electric, packaged hybrid hot water systems.

FUSION harnesses the highly respected FPi32 ASHP, a high-pressure ATSH calorifier with electric immersion, controls, and metering. Working together, this provides a reliable, high-temperature, sustainable and cost-effective system for meeting typical continuous hot water demands (from 257 up to 377 litres/hour) found in new commercial builds as well as refurbishment projects where gas and associated flueing is either not possible or no longer desired.

The system specification is available in 16 variants with 6 or 10 kW ASHP preheat and 9 or 12 kW electric immersion top-up.  Capacities ranging from 200 to 500 litres all rated at 10 BAR for high-pressure applications. This makes FUSION highly adaptable for a wide range of applications typically seen in public sector buildings. The FPi32 ASHP is specified to supply the preheated hot water throughout the year, even when ambient air temperatures drop as low as -25°C. The stainless steel construction of the ATSH also makes it an excellent all-rounder, resistant to soft water corrosion and, with Adveco’s own low heat intensity electric immersion specification (6W/cm2) the calorifier is more resistant to scale build-up in hard water areas.

FUSION ensures the ASHP preheat and immersion within the ATSH work seamlessly to deliver the highest operational efficiencies. Physical design spaces apart the low-situated high-efficiency preheat coil from the electric top-up immersion. Then dedicated controls and integrated metering monitor temperature and water flow throughout the system. This enables FUSION to make the greatest gains possible from the heat pump even though ambient temperature and system demands will fluctuate. These gains are then used to offset as much of the direct electrical top-up as possible, providing 53% carbon emissions savings (compared to equivalent direct electric only systems) and helping control the operational costs of providing business-critical hot water.

And without the need for a PHE or additional buffer tank, the capital costs of a hybrid hot water system become more manageable while making major gains in terms of space-saving. Something often identified by customers as a core requirement for smaller properties that may lack dedicated plant room space.

For commercial buildings with small to medium basin and sink led hot water demands and a desire to embrace a more sustainable business model, the FUSION hybrid hot water provides a single, easy to accommodate, highly effective response. One that provides optimum efficiencies, dramatically reduces carbon emissions and assures building regulations designed to lower carbon emissions from commercial projects are being met.

Learn more about ADVECO’s FUSION Hybrid Hot Water System

FUSION Commercial Hybrid Hot Water Systems from Adveco

  • FUSION is a complete range of low carbon hybrid heat pump and electric hot water systems
  • Resilient stainless steel water heating suitable for all UK regions
  • Compact design for new build and refurbishment projects seeking greater sustainability

Commercial hot water specialist Adveco, introduces the FUSION FPH-S range of low carbon, all-electric, packaged hybrid hot water systems. FUSION harnesses Adveco’s FPi32 Air Source Heat Pumps (ASHP), a high-pressure ATSH calorifier with electric immersion, controls, and metering to provide a reliable, high-temperature, sustainable and cost-effective system for new commercial build and refurbishment projects.

FUSION is available in 16 pre-specified variants with 6 or 10 kW preheat and 9 or 12 kW electric top-up, with capacities ranging from 200 to 500 litres all rated at 10 BAR for high-pressure applications. Able to meet a range of continuous capacity hot water demands from 257-377 litres/hour makes FUSION highly adaptable for a wide range of commercial buildings.

The FPi32 ASHP is specified to supply a working flow of 50°C for system preheat throughout the year, even when ambient air temperatures drop as low as -25°C. Electric immersion top-up then raises system temperatures in the calorifier to the necessary 60°C to meet commercial requirements for safe hot water demands. The stainless steel construction of the ATSH also makes it an excellent all-rounder, resistant to soft water corrosion and, with FUSION’s unique low electric immersion heat intensity (6W/cm²), is more resistant to scale build-up in hard water areas.

The physical design, dedicated controls and integrated metering ensure the ASHP preheat, and immersion work seamlessly to deliver the highest operational efficiencies. This enables FUSION to make the greatest gains possible from the heat pump, even when ambient temperature and system demands fluctuate. These gains offset much of the direct electrical energy usually required, delivering 53% carbon emissions saving and helping control the operational costs of providing business-critical hot water.

“For organisations with small to medium basin and sink led hot water demands and a desire to embrace a more sustainable business model, the FUSION FPH-S range provides a single, easy to accommodate, highly effective response,” says Bill Sinclair, technical director, Adveco. “By choosing one of these packaged hybrid water systems you gain optimum efficiencies, lower your carbon emissions and can be assured building regulations are being met for your commercial project.”

Fusion FPH-S Features

  • 16 pre-sized variants to meet a wide range of applications
  • 200, 300, 400 and 500-litre capacities
  • 6 or 10kW ASHP preheat
  • 9 or 12kW direct electric immersion heating
  • 257-377 litres/hour continuous capacity
  • 10 BAR high-quality AISI 316Ti and 316L stainless steel vessel (PED (97/23/EC), EN 12897)
  • Dedicated control system for simple operation and maintenance checks
  • Lower global warming potential with R32 ASHP
  • Compact space-saving form factor

Calorifiers and Hot Water Storage in Corrosive Water Conditions

For many companies, the assured availability of hot water is a business-critical issue, but one that can quickly become costly for those operating in the southwest and northwest of the UK, the Welsh coast and throughout Scotland. With a low pH, low total dissolved solids (TDS) and negligible buffering capacity, these naturally soft water areas prove highly corrosive to glass-lined vessels used as calorifiers and hot water storage.

Glass is, given the right conditions, generally resistant to attack from most chemicals and corrosive materials and easier to clean, making it a popular choice for lining steel vessels used in hot water systems. But corrosion is a complex phenomenon, and in naturally soft water conditions, despite the use of sacrificial anodes, glass-lined vessels can rapidly succumb to critical corrosive damage.

Pressure to Perform

In addition, the taller the structure, the greater the pressure requirements on the system, particularly since a common design choice is to locate the plant room in the basement. In order to meet, even small demands with a consistent, strong flow of hot water systems inevitably are oversized, adopting a larger, often bespoke tank.

This immediately exacerbates the existing threat, as oversizing, or the failure to correctly balance water flow also contributes to system corrosion. Oversizing of the pumps leads to high-velocity hot water circulating through the system and suspended solids in the water are driven against the metal leading to erosional corrosion. This process helps accelerate the soft water corrosion at points where water changes direction, such as when passing into or through tanks.

Glass-lined water vessels used as calorifiers and hot water storage under these conditions can potentially fail due to corrosion in a matter of just months – even with the use of sacrificial anodes. For these reasons, manufacturers will reduce or have even ceased to offer warranties on glass-lined products installed in these soft water regions. As a result, their specification into projects in these regions really can be a false economy.

Change to Resistant

Far more resistant to these water-side assaults are stainless steel vessels. Although there is a higher upfront cost, this would be easily offset by the relative longevity of the appliance. However, projects with smaller, yet higher pressure hot water demands, will still face the issue of oversizing. This further extends capital costs, of products, installation and the need for greater plant room space. As a result, project costs can become prohibitive for stainless steel, resulting in the specifying of the less expensive glass-lined alternatives gambling that they will prove resistant enough in the mid-long term.

Adveco addresses these concerns with its ATSx range of compact stainless steel, high-pressure hot water tanks. Specifically designed to serve as buffer vessels (ATSB) and indirect hot water calorifiers suitable for use with lower capacity, high-pressure commercial applications in soft water areas. The ATSx range provides specifiers and contractors with a wide choice of calorifiers and hot water storage vessels all rated to 10 bar as standard, which are by far the most efficient and cost-effective choice for businesses with smaller system demands.

Another advantage provided by the indirect water heaters in this range (ATSI, ATST, ATSH & ATSR) is that due to the transferral of heat through the walls of the heat exchanger element the two fluids do not mix. This allows for more options in terms of the external heat supply and introduces a range of renewable technologies that use other fluids for heat transfer including solar thermal collectors and Air Source Heat Pumps. The twin coil ATSR has been specifically designed for these lower-temperature renewable applications. These calorifiers are also relatively simple to install, since there is no burner, there is no need for a gas supply to be directly connected to the appliance and the is no requirement for a flue.

As with any hot water application, understanding the relationship between storage and recovery, and correct sizing is extremely important for efficient and cost-effective operation. Integrating a stainless steel calorifier within a hot water system gives you a number of design options, with a large efficient boiler a calorifier can be smaller avoiding unnecessary capital and ongoing operational expenditure. At 200 to 1000 litres the ATSx range provides a compact, tough resolution for lower demands applications in those soft water areas. If your project has pressure requirements greater than six bar, then the ATSx vessels are by far the most efficient and cost-effective choice for your project.

If the boiler is smaller, or demands for hot water are greater, then going too small means the storage could prove inadequate and the system will not achieve its operational requirements. For projects with larger demands or requiring greater customisation Adveco can support the project with the SSB, SSI and SST ranges of bespoke stainless steel calorifiers and hot water storage vessels.

Discover more about the Adveco ATSx range.

Learn more about soft water corrosivity.


Adveco commercial hot water and heating. Speak to Adveco about tackling global warming through efficient, low-carbon commercial hot water and heating systems (For schools, hospitals and care homes too!)

Call us on 01252 551 540 or see our other contact details.

 

Bespoke Hot Water and Heating, Celebrating 50 Years Of Excellence

For the past 50 years, Adveco Ltd has been the recognizable face of A.O. Smith in the UK. As with so many businesses, it started with a simple idea from founder Daniel O’Sullivan to improve efficiency and save costs, two core ideals that remain at the heart of everything the business still does today. In 1971, the focus was to support the launderette industry by introducing a simple hot water application that utilized a glass-lined boiler and galvanized hot water storage tank. This unique approach helped to define the early days of the business and created a new market and new demands. The company was later recognised by BSRIA as the instigator of direct gas-fired water heaters in the UK. Today, the company is one of the trusted specialist providers of low-carbon, bespoke hot water and heating to the building services industry.

The first ever UK installed A.O. Smith glass line boiler

Adveco operates across the commercial built environment, working with consultants, specifiers, and designers, providing informed support and partnership to design and deliver systems optimised to be highly efficient and cost-effective. Contractors gain a single, versatile, specialist sales resource that ensures delivery of the most cost-effective system. Facility managers are supported through product remote monitoring, technical support, warranty, and maintenance service to ensure system longevity and help realise a low total cost of ownership.

As a result, our systems can be found across the country, from prestige city sites to university and school accommodations, hospitals and care homes, supermarkets, sports stadia, hotels, restaurants and leisure facilities of all sizes. It is pretty much guaranteed you will have used bespoke hot water and heating from a system Adveco has designed, supplied, and maintains without ever realising it.

50 Years of Bespoke Hot Water Innovation

Daniel O’Sullivan and the sales team inspect the latest models from A.O.Smith

Founded as Advance Services (Sales) Ltd, that initial year defined much of the history of the business with a close partnership formed with the American based water heater manufacturer A.O. Smith. The company would quickly become A.O. Smith’s sole UK distributor, even though it had elsewhere opted for a multi-distributor approach. Here it had become clear that the success in the UK had stemmed from working with a focused single market entity, and the partnership was further ratified in 1998 when Advanced Services Sales Ltd became A.O. Smith’s sole official partner and under its new agreement started trading as A.O. Smith Water Products, and then latterly as A.O. Smith Water Heaters (Adveco AWP) Ltd.

Although Daniel retired in 2000, his son David O’Sullivan continued to grow the family business, maintaining its fierce independence and commitment to innovation. More than just offering distributions services, A.O. Smith Water Heaters had grown a wider reputation for its own in-house engineering capabilities, providing a wealth of knowledge for commercial hot water application design and post-installation service.

In 2015, Adveco Ltd. was established to further develop this capability, as well as providing complementary products to enhance the company’s offering. Operating as an independent sister company to A.O. Smith Water Heaters, Adveco has expanded in recent years, establishing European sales offices and continues its commitment to the design, supply, commissioning and full after-sales support and maintenance servicing, of more than 1,000 commercial boiler, hot water, and solar thermal systems every year.

More recently A.O. Smith has returned to its original multi-distributor model, although its own brand product ranges remain with Adveco / A.O. Smith Water Heaters in the UK. This process has given impetus to the modernization of the business. Though continuing to provide a full range of commercial gas and electric water heaters, boilers, and solar thermal systems from the A.O. Smith portfolio, Adveco is evolving to become a single point of contact for a wider range of commercial bespoke hot water and heating systems that address a market being redefined by the drive to sustainability and the target of Net Zero by 2050.

RP MD Boilers.

MD Floor Standing Boiler

We continue to see increasing demand for near-instantaneous and instantaneous water heating across a variety of projects and are constantly exploring ways to meet this often technical challenge for commercial applications. Within those hot water applications, the highly efficient A.O. Smith BFC Cyclone and Innovo are always a popular choice for commercial projects requiring hot water. The MD range of floor standing condensing gas boilers, which were highly commended in the HVR Awards on launch, have also proved to be very popular for commercial heating, boasting a seven-year parts and maintenance warranty which we are able to offer due to the strong, corrosion-resistant titanium steel construction and smart balancing of the pre-stacked heat exchangers.

Despite the hyperbole, gas remains, at least for the time being, a core element for commercial systems. Familiar, well understood and extremely cost-effective, it remains an important part of the product portfolio for delivery of domestic hot water (DHW) applications and heating.  Adveco’s DHW offering has extended with a range of new stainless steel condensing water heaters to address soft water areas in the UK, alongside a range of stainless-steel cylinders, packaged plate heat exchangers and electric immersion kits which enables greater use of clean electricity for primary and backup heating of water across a range of bespoke tanks. Although we would characterize ourselves as hot water specialists, we can still address the specialist needs of commercial-scale heating with our ranges of floor-standing and wall-hung gas boilers (MD), carbon steel heating buffers (MSS) and thermal storage (MST).

A More Sustainable Future

RP Solar thermal.

Adveco solar thermal with drainback technology

Perhaps most exciting, has been the work to develop systems that are capable of better integrating low carbon and renewable technologies. In 2009, Adveco committed to development in this space with the introduction of its first Solar Thermal systems, working in partnership to develop critical drainback technologies that addressed the massively costly issue of stagnating solar fluid in panels and pipework. There is no doubt in our minds that as the demands for lower carbon applications grow, a combination of Solar Thermal and traditional gas will see a resurgence. But there is a degree of complexity that needs to be recognised and that is where specialist knowledge pays dividends when investing in both new and refurbished properties. Solar Thermal also has a role to play in more advanced hybrid systems that will be more dependent on electricity, the use of heat pumps and heat recovery technologies.

FPi32 commercial Air Source Heat Pumps (ASHP).

FPi32 Air Source Heat Pump

In recent years, Adveco has struck several exclusive manufacturing partnerships to develop air source heat pump (ASHP) technology and products expressly for the generation of preheat for DHW systems. This is necessary to address both building regulations in the UK and our varied Northern European climate.  The fruits of those partnerships have been the launch of the FPi range of Air Source Heat Pumps (ASHP) in 2019, quickly followed by the introduction of the L70 heat pump for larger-scale projects. This year the FPi Range was completely revised with the introduction of a new system based on the more environmentally friendly R32 refrigerant which delivers considerable advances over its predecessors. This development programme continues at pace as we hone designs that help meet the high-temperature demands of commercial DHW. Our development work also includes the creation of the HVR Awards recognised HR001 boxed heat recovery system which was designed and manufactured in-house to support businesses making regular daily use of commercial-grade chiller and freezer units. Commercial systems offer a range of opportunities for heat recovery, essentially gaining ‘free heat’ that can be used to offset energy demands and help reduce carbon emissions from daily operations. Adding heat recovery into your sustainability mix is frankly a no brainer and we continue to explore opportunities for its application within commercial systems.

Packaged Plant Rooms.

Low carbon hot water systems in an Adveco Packaged Plant Room

Bringing all these varied elements together is Adveco’s packaged plant room offering, a bespoke hot water and heating system build that leverages all the advantages of offsite construction. Pre-fabrication is a tried and tested way of bringing mechanical and electrical systems to a live construction site, countering the challenges of complexity, limited space, limited time, and the need to work around other contractors. The concerns over post-Brexit/Covid rising costs, construction projects struggling to attain raw materials as well as a shortfall of experience on-site cannot be discounted. Offsite construction is therefore a great way to address these potential fears.  It just makes things on site much easier and crucially helps to accelerates those all-important project timelines which in turn can help offset other unforeseen project costs.

Packaged plant rooms can almost be treated as a microcosm of our work, a large proportion of which we create as bespoke applications and that includes our smart control systems. So, for Adveco, almost all our projects begin with application design. Without doubt, the rapid changes to legislation relating to efficiency and emissions as we move towards Net Zero by 2050 is having far-reaching implications for our industry. The challenge, certainly for commercial buildings, is to design, supply and then monitor a system for its full lifecycle to ensure the various elements of a system work together, not against each other. The problem is that we are increasingly seeing more cases of the wrong technology being used for the right application: from oversizing for the building, or failure to account for summer heating loads, to under-sizing solar buffer vessels and poorly executed combinations of renewables. Poor sizing has always been a key failure, driving up CAPEX and unnecessarily raising OPEX, but these more varied system design errors must be seen as a result of the rush to be environmentally friendly compounded by the confusion over what that really means in terms of practical technology choices. As an HVAC business, you simply cannot stand still, customers won’t allow for that, so being versatile in the ability to deliver bespoke, engineered systems, is becoming even more of an advantage for us as we look at the changing needs of customers, both in the short and long term. Our application design team provide professional support throughout all stages of a project, from selecting the pertinent product to meet a specific demand to complete system design.  All projects are meticulously sized by our in-house team of qualified industry professionals. This ensures that all applications receive a bespoke, cost-effective design that avoids the typical pitfalls described.

Looking Forward

All eyes are now on the 26th UN Climate Change Conference (COP26) and an expectation of greater clarity from the Government over how the commercial sector will be supported on the road to Net Zero. At Adveco, our approach is to be prepared for all options, whether the future of commercial heating and hot water in the UK will be designated all-electric, hydrogen/green gas, or a mix of the two. This continues to drive our exploration of new technologies and reiterates the advantages of being independent. It enables us to create these critical technical partnerships that allow us to be quick on the uptake of new, or more relevant technologies, whilst continuing to leverage our own deep technical experience. In the near term, we will be further developing our portfolio of heat pumps for commercial applications, as well as designing new hybrid systems that take best advantage of this and other technology. We also see the huge, and cost-effective potential for the large scale roll-out of hydrogen to the commercial sector. All this will require a greater demand for complete system design of which we have deep experience providing bespoke hot water and heating. Ultimately, we come back to the earliest tenet of the company, an unbeatable focus on commercial hot water systems. We already have a strong offering, whether gas and solar, or all-electric with heat pumps, and see this consultancy work, especially for D&B contractors, driving our future growth out beyond 2050.

Adveco ATSx Stainless Steel Hot Water Tanks for Soft Water Areas

  • A complete range of indirect hot water calorifiers and buffer vessels.
  • Corrosion-resistant stainless steel construction for soft water areas.
  • Designed for high pressure, lower demand projects.

Commercial hot water and heating specialist Adveco, announces the ATSx range of stainless steel hot water tanks. The new product range encompasses five classes of vessel up to 1,000 litre capacity at 10 bar as standard to serve as buffer vessels and indirect hot water calorifiers. The range is designed to provide a more economic choice for high pressure, lower capacity commercial applications in soft water areas.

With single coil, twin coil and plate heat exchanger options for maximising transfer of energy, the ATSx stainless steel hot water tanks offer consultants, specifiers and contractors a broader set of options for the storage and delivery of domestic hot water (DHW) in soft water areas for their projects.

ATSI – Single coil indirect water heater.

ATST – Twin coil indirect water heater.

ATSH – Single double-helical high-capacity coil indirect water heater.

ATSR – Twin coil indirect water heater for lower-temperature renewable applications.

ATSB – Storage/buffer tank without coil.

Speaking of the launch of the ATSx range, Adveco’s Technical Director Bill Sinclair said:

“If your project has smaller hot water demands, but with pressure requirements greater than six bar, such as in taller buildings with a basement plant room, then the ATSx vessels are by far the most efficient and cost-effective choice for your project,”

Constructed from corrosion-resistant AISI 316Ti and 316L stainless steel, all ATSx tanks are designed, manufactured, and tested to the requirements of the Pressure Equipment Directive (97/23/EC), EN 12897.

The ATSx range is also supported by a choice of options and ancillaries from Adveco including control and overheat thermostats, destratification pump kits and unvented kits.

For projects with larger demands or requiring greater customisation in soft water areas, Adveco offers its SSB, SSI and SST ranges of bespoke stainless steel calorifiers and buffer vessels.

Discover more about Adveco’s ATSx range


Adveco commercial hot water and heating. For more information about Adveco’s ATSx stainless steel hot water tanks, call us on 01252 551 540 to discuss requirements, sizing etc.

 

SSI – True Versatility for Bespoke Commercial DHW systems

A commercial indirect calorifier is characterised by not having an integral burner, instead, they typically contain a single, high-output internal heat exchange coil situated at low level which heats water circulated over it. The fluid in the coil (which is immersed in the water within the vessel) is filled by heated liquid provided by a separate appliance – typically a gas boiler, heat pump or solar collector. The heat is then exchanged from the coil into the vessel, hence indirectly heated.

Without a directly connected gas supply, and therefore no need for a flue, an indirect calorifier is simpler to install as part of a wider heating and hot water system. The insulated storage tank retains energy longer, permitting hot water production year-round in greater quantities and at a reasonable cost.

The indirect calorifier that is also a direct heating appliance

Designed specifically to serve domestic hot water (DHW) installations, the Adveco Stainless Steel Indirect (SSI) range is available in a range of tank sizes, with a plethora of options since it can be specified or upgraded at any time with a range of coil options. Because access to the SSI’s coil is made easy for upgrading purposes, it is also highly accessible for cleaning and maintenance purposes.

Unlike most similar vessels on the market, the highly modular SSI range also incorporates the option to add an electric immersion heater. With a broad selection of immersions available, the SSI can be turned into a direct heating appliance, perfect for cost-effectively building redundancy into a system that could otherwise be reliant on continuous gas supply.

Commercial installations where heat is already being generated, such as light industry, leisure sites and hospitals are perfect locations for the use of an indirect calorifier. If an application has modern boilers deployed, such as Adveco’s MD floor standing boilers and MD wall mounted boilers, they can then be harnessed for both the heating circuit and the DHW system, so no need for a dedicated boiler to heat the calorifier, but the boiler does need to be operating year-round.

In the summer when the space heating is not needed, all of the heat is used for hot water preparation. During the winter, when the indirect water heater is used for the heating, only a small fraction of the heat is used for DHW.

There are system advantages to this approach as continuous use of the boiler for DHW helps prevent costly deterioration which can occur if a boiler is idle for long periods of time. At Adveco, we can advise on the best options for your application, sizing the system and recommending optimal appliances to meet your building’s DHW demands. The Adveco SSI’s wide range of options lends itself perfectly to the development of bespoke systems and means we can deliver the most relevant, efficient and therefore cost-effective solution to meet your particular needs for commercial hot water.


Adveco - Calorifiers and Stainless Steel Indirect tanks for commercial hot water systems.Speak to Adveco about stainless steel indirect tanks (calorifiers) for your bespoke commercial hot water systems.

Call us on 01252 551 540 or visit the contact us page.

SSI 1500 Stainless Steel Indirect

Is a Calorifier Right for My Project?

A calorifier is a commercial-grade indirect-fired water heater that provides hot water in a heating and hot water system.

It is designed for projects requiring large volume storage of water at high temperature, but rather than using a burner, the water is heated by heat exchanger coils containing liquid from another heat source, such as a boiler.

In a typical application, the hot water directly heated by a gas or electric boiler passes through the calorifier and is used, via heat exchange, to heat up the cold water in a separate system of pipework. This does mean that a calorifier cannot react as quickly to demand as a direct-fired water heater, however, with the calorifier working as a buffer and storing the hot water, it reduces the operational demand placed on the boiler. With the boiler no longer required to work as hard to meet the domestic hot water needs (DHW) of a building, energy is saved, costs are reduced and emissions fall.

With the increased efficiency of modern condensing gas boilers, having a dedicated hot water boiler to heat the calorifier is no longer a requirement as they can easily supply heat to both the calorifier and the heating system. The compact Adveco MD range of gas condensing boilers, for example,  are both high capacity and can be arranged in cascade to scale to provide both heating and, with an indirect calorifier, the DHW needs of a wide variety of commercial projects. It must be noted that when space heating is not required, such as during the summer months, the boiler will still be required to provide heat for the hot water system.

Another advantage of the indirect approach to heating is that due to the transferral of heat through the walls of the heat exchanger element the two fluids do not mix. This allows for more options in terms of the external heat supply and introduces a range of renewable technologies that use other fluids for heat transfer including solar thermal collectors and Air Source Heat Pumps. At Adveco, these options are supported by a variety of calorifiers. The Stainless Steel Indirect (SSI) range, for example, is supplied with a single high-output internal heat exchange coil at low level to serve as an indirect calorifier in DHW installations. For more complex and renewable-based systems, the Stainless Steel Twin-Coil (SST) range offers a pair of independent internal heat exchange coils to serve DHW systems. Each high-output coil can be used with a separate heat source, enabling effective integration of renewable technologies or multiple heat sources, or alternatively can be combined to increase the heat transfer capacity from a single high-output source.

Also, by separating the supplies you reduce the risks of external contamination, a build-up of scale in hard water areas or the corrosive effects of soft water.

Calorifiers are also simple to install. Since there is no burner, there is no need for the gas supply to be directly connected to the appliance and the is no requirement for a flue.

As with any hot water application, understanding the relationship between storage and recovery, and correct sizing is extremely important for efficient and cost-effective operation. Integrating a calorifier within a hot water system gives you a number of design options, as a larger calorifier means the boiler can be smaller, or the reverse if the existing system has a large efficient boiler. Understanding the hot water demand is critical. If demand is not so great, then using a larger calorifier can lead to unnecessary capital and ongoing operational expenditure. Go too small and the storage could prove inadequate and the system will not achieve its operational requirements.

Attaining the correct balance of demand and efficient, cost-effective supply is what ultimately defines a successful system, whether it be for a hotel, hospital, school, office or leisure facility. Each will have their own parameters to be met, and Adveco specialises in providing the widest range of calorifiers, boilers and renewables to meet the bespoke needs of any project.

The patterns of hot water usage and recognition of periods of peak demands often make sizing a complicated process, with many systems overcompensating and, by being oversized become more costly and less efficient. At its simplest, a commercial system should hold an hour of hot water output in storage, but the function of the building, its population and activities will adjust requirements, for example, where hospitals will typically exhibit a 24/7 demand for hot water, schools and offices may be limited to just 7½ hours per day. In some refurbishment scenarios, we will also see a physical limitation of space available for DHW storage, in which case a system will put more demand on the boiler or renewable to increase the output for preheating, reducing the required size of calorifier.

If there is an availability of space, or a prefabricated packaged plant room approach can be used to relocate plant to previously unused space – such as a rooftop or car park – there is an opportunity to incorporate multiple calorifiers and thereby divide the total storage demand. This approach not only provides system resilience, but for commercial sites that exhibit predictable seasonal demands such as leisure centres, campsites and hotels, it allows for elements of the system to be shut down during off-peak periods. The other real advantage of adopting a packaged plant room approach to a DHW system is that the boiler or ASHP providing the preheat can be located in close association with the calorifier. The physical proximity helps negate problems of heat loss between the boiler, pipework and calorifier which can be detrimental if more widely separated in a system.


Adveco commercial hot water and heating. Discover more about Adveco water heating, water buffers and calorifiers, and how we can help size your DHW application.

Call us on 01252 551 540 or visit the contact us page.

SSI 1500 Stainless Steel Indirect (Calorifier)

Taking the Indirect Approach to your Heating Needs

The Stainless Steel Indirect (SSI) range from Adveco is designed to serve as an indirect calorifier in domestic hot water (DHW) installations. The unit has no integral burner, instead, it contains a single, high-output internal heat exchange coil situated at low level which heats water circulated over it.

Commercial installations where heat is already being generated, such as light industry, leisure sites, and hospitals are perfect locations for the use the SSI as a method of indirect heating.

Stainless Steel Indirect (SSI) calorifier.

Stainless Steel Indirect (SSI) calorifier.

Without a directly connected gas supply, and therefore no need for a flue, an SSI indirect calorifier is simpler to install as part of a wider heating and hot water system where the heat is provided by a separate appliance – typically a gas boiler, heat pump or solar collector. The fluid in the coil – which is immersed in the water within the SSI – is filled by heated liquid (water or solar fluid) and the heat then exchanged from the coil into the vessel, hence indirectly heated. The insulated storage tank retains energy longer, permitting hot water production year-round in greater quantities and at a reasonable cost.

Commercial systems should harness the efficiency of the modern boiler for both the heating circuit and the DHW system. This counters requirements for a dedicated boiler to heat the calorifier. During the winter, when the indirect water heater is used for the heating, only a small fraction of the heat is used for DHW. In the summer when the space heating is not needed, all of the heat is used for hot water preparation, so this does mean the boiler needs to be operating year round. There are system advantages to this approach as continuous use of the boiler for DHW helps prevent costly deterioration which can occur if a boiler is idle for long periods. The SSI coil is also easy to remove for cleaning and maintenance purposes.

Available in a range of tank sizes, SSI can also be upgraded at any time with a range of coil options making the design highly modular. There is even the option to add an electric immersion heater, turning the SSI into a direct heating appliance, perfect for cost-effectively building redundancy into a system that could otherwise be reliant on a continuous gas supply.