mould, virus and dust particles IAQ

IAQ in Commercial Buildings

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Given that most of us typically spend up to 90% of our time inside buildings, indoor air quality (IAQ) is a serious consideration, especially as it relates to the health and comfort of the people who occupy it. Poor IAQ can have several negative health effects, including respiratory problems, headaches, fatigue, and allergies. It can also lead to decreased productivity and increased absenteeism.

Despite hybrid working becoming firmly entrenched across the country, IAQ remains an especially important issue within commercial buildings, given the significant time people still spend within them, whether working or visiting. IAQ can be affected by a variety of factors, including the building’s ventilation system, the materials used in its construction, and the activities that take place inside it.

The World Health Organisation (WHO) guidance on air quality has advised member states to consider air pollution to be as big a threat to human health and well-being as climate change and adjusted almost all of its previous maximum target levels for airborne pollutants downwards. It linked long-term exposure to even relatively low concentrations of ambient and indoor air pollution to lung cancer, heart disease, and strokes – putting the health impact of pollution on a par with poor diet and smoking.

There are several things that can contribute to poor IAQ in commercial buildings. Some of the most common causes include:

Many building materials, such as carpets, furniture, and paints, can release harmful pollutants into the air. These pollutants can include volatile organic compounds (VOCs), formaldehyde, and asbestos.

Pollutants from activities that take place inside a building can also contribute to poor IAQ. For example, cooking, smoking, and using cleaning products can all release pollutants into the air.

And if a building’s ventilation system is not working properly, it can’t remove pollutants from the air. This can lead to a buildup of pollutants and poor IAQ.

When the Covid-19 pandemic struck, highlighting the role played by poor-quality indoor environments in the spread of viruses and other airborne contaminants, new standards were deemed necessary, elevating publicly available specifications in development by the British Standards Institute and BESA to a full British Standard BS40102-1.

The new standard gives recommendations for measuring, monitoring, and reporting indoor environmental quality (IEQ) in all types of non-domestic buildings. It includes an evaluation and rating system for air quality, lighting, thermal comfort, and acoustics.

Given that building retrofit work carried out to improve energy efficiency had, in many cases, led to poorer quality ventilation this new evaluation will give building managers a benchmark score to help them identify areas of below-par performance. This enables planned improvements which include IEQ measures in any retrofit and renovation work to improve the health and well-being of occupants.

To meet the new standard organisations will need to tackle conditions that have a direct impact on human health including humidity, and excessive levels of CO2, CO, NO2, volatile organic compounds (VOC), airborne particulates and mould.

Adveco has for many years operated a system of checks to ensure the comfort and safety of buildings, including initial system commissioning to ensure correct and safe installation of appliances, in particular its gas-fired water heating and flues. This is especially important in controlling and safely removing any CO2 and NOx emissions from proximity to building users. Regular annual service is a critical facet of such safety checks, yet can be a process that slips once products are no longer under their initial warranty period. This is both a false economy and of potential danger to building users. While new builds will embrace all-electric systems which effectively negate NOx and on-premise CO2  generation, pre-existing commercial sites need to be increasingly vigilant, especially when ageing gas-fired systems remain in use. Mould, a type of fungus which produces airborne spores, is also a contributor to poor IAQ so regular service also helps to identify or prevent cases of damaging corrosion (in soft water areas) and limescale build-up (in harder water areas) which can lead to leaks that then encourage growth of mould in plantroom areas.

Setting IEQ performance benchmarks will make it easier for facilities managers to target problem areas, but British Standards will require further tightening if they are to keep abreast of the WHO’s more stringent guidelines. 

If you operate buildings with ageing gas-fired hot water systems and have concerns about IAQ or wish to reduce carbon emissions as part of a sustainability strategy, speak to Adveco about Live Metering, system assessment and replacement options. Whether looking for high-efficiency, ultra-low emission gas appliances such as AD / ADplus water heaters and MD boilers, or a transition to electric boilers, heat pumps or solar thermal we can help with system assessment, replacement design, supply and ongoing service for more efficient, comfortable and safe working environments.   

newsletter logo September 2023

Read The Adveco September 2023 Newsletter

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Welcome to the Adveco September 2023 newsletter. This month we consider the opportunities solar thermal systems present for both gas-fired and electric water heating systems in commercial buildings. We consider the potential net zero impacts of the forthcoming Future Buildings Standards and the recently introduced EPC ratings on commercial rentals. And are pleased to announce our finalist status in both the Energy Awards and the Heating & Ventilation Review (HVR) Awards…  

Click here to read the Adveco September 2023 Newsletter

Adveco August Newsletter

Read The Adveco August 2023 Newsletter

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Welcome to the Adveco August 2023 newsletter. This month we consider how blending technologies enables commercial properties to achieve greater sustainability of hot water supply. We also track the impact of the Public Sector Decarbonisation Fund as it ushers in phase 3c, new Buffer cylinders for heating projects and get an update on a project to counter limescale in restaurant applications. 

Click here to read the Adveco August 2023 Newsletter

zero carbon footprint for the public sector

Public Sector Decarbonisation Latest Funding Phase

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The UK Public Sector Decarbonisation Scheme (PSDS) is a government-funded program designed to support the UK’s net zero emissions target by 2050 by providing grants to public sector bodies to help them decarbonise their buildings. This is important as most of the buildings in the public sector still rely on burning fossil fuels for heating, hot water, and catering. 

Phase 1 and Phase 2 of the PSDS have been successful in helping to decarbonise public sector buildings in the UK. The schemes have awarded over £1.75 billion in grants to over 1,300 public sector bodies, which have helped to decarbonise more than 2,000 public buildings. These projects have resulted in a reduction of more than 1.25 million tonnes of carbon emissions.

Who can use the PSDS?

The scheme is open to a wide range of public sector bodies, and it provides significant financial support for decarbonisation projects. If you are a public sector body that is looking to reduce your carbon emissions, the PSDS is a great option to consider.

The PSDS is open to all public sector bodies, including central government departments, local authorities, schools, hospitals, police forces, fire and rescue services and other public buildings.

The PSDS has been a successful program so far. In Phase 1, which ran from 2020 to 2022, the scheme awarded over £1 billion in grants to more than 1,000 public sector bodies. These grants have helped to decarbonise more than 1,500 public buildings, resulting in a reduction of over 1 million tonnes of carbon emissions.

Phase 2 of the PSDS, which ran from 2021 to 2022, awarded £75 million in grants to a further 300 public sector bodies. These grants have helped to decarbonise more than 500 public buildings, resulting in a reduction of a further 250,000 tonnes of carbon emissions.

Why should public sector bodies apply for funding?

There are a number of reasons why public sector bodies should apply for funding from the PSDS. These include:

  • Helps reduce fossil fuel emissions as well as making public buildings more comfortable and cheaper to warm. 
  • To reduce their carbon emissions and help the UK reach net zero.
  • To save money on energy bills.
  • To improve the energy efficiency of their buildings.
  • To create jobs in the low-carbon economy.
  • Gain ongoing client and technical support on project delivery. 

Phase 3c of the PSDS

Phase 3 of the Public Sector Decarbonisation Scheme, worth £1.425bn, was launched on behalf of the Department for Energy Security and Net Zero in 2021 to supply grants to public sector bodies over the period 2022 to 2026. Phase 3c of the PSDS was launched this month.

For Phase 3c of the PSDS, an additional financial year of funding has been granted by the Department. This funding increases the value of the overall funding to the scheme and will enable Phase 3c projects to deliver across two financial years.

Phase 3c of the Public Sector Decarbonisation Scheme has up to £230 million available in 2024/25. The budget available in 2025/26 will be confirmed this autumn though applicants should assume a broadly balanced profile across 2024/25 and 2025/26.

The Application Portal for Public Sector Decarbonisation Scheme Phase 3c is expected to open in the autumn and comes with soft sector caps (divided by Health, Education and Other) to ensure a more balanced distribution of funds across sectors. 

Applicants can submit separate applications for separate projects or combine several projects for delivery across one or two financial years. Applicants can also include energy efficiency measures and other enabling works, that are additional to the replacement of the fossil fuel heating system, where they support a whole-building approach to decarbonisation. 

To apply for Phase 3 funding visit the PSDS website or visit Adveco’s Net Zero resources to understand how funding can be used to support decarbonisation projects that deliver results today. For public sector buildings with gas-fired systems please talk to us about metering your buildings to understand how low-carbon technology can be successfully used to lower carbon emissions without excessively driving up capital funding.  

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All Electric ? Sustainability & Water Heating Pt.3

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In this three-part series, Adveco has so far addressed the role of air source heat pumps and solar thermal as a source of low carbon preheat, in this final part, we consider the future of gas and the adaptation to all electric applications for implementing more sustainable hot water in commercial buildings.  

Read Part 1 Sustainability & Hot Water – Which Path Is Right For Commercial Properties? 

Read part 2 sustainability & Hot Water – Using The Sun

Despite the pressure to address carbon emissions in building stock in the UK, the fact is we are still waiting for clear advice at a government policy level. The final decision on energy solutions remains unresolved. So do you opt to go all electric with equipment now on the basis that the grid will become zero carbon or hold out for the option of carbon-free gas such as Hydrogen, which in terms of infrastructure change and refurbishment would be potentially quicker, cheaper and less disruptive.

As indicated, if your building has a gas connection and has high hot water demands it remains the most cost-effective option. Additionally, new gas-fired appliances operate with ever-reduced emissions, and most are ready to accept the initial proposed 20% hydrogen blends in the gas grid as early as 2024 without requiring any alteration. ‘Hydrogen Ready’ units are, with a replacement of the burner and pre-mixer, even capable of burning 100% hydrogen, but that scenario is some time away. Should hydrogen be accepted by the government as a function of net zero we would not expect 100% feeds to be in place nationally until 2040 with the grid changeover beginning in the early to mid-2030s. Retaining an existing gas connection, therefore, provides a degree of futureproofing should green gas technology be embraced.

What is clear though is that the latest building regulations (Part L, 2021) have radically revised the carbon intensity of electricity from 519g CO/kWh ten years ago to just 136 today. Gas in the same period has fallen from 240 to 233. Whilst the regulations do not yet exclude gas, they do advantage the adoption of all electric systems. We have demonstrated that renewables have a critical role in reducing the carbon emissions of a system, as well as offsetting the costs of heating water with direct electricity.

Gas-based hot water applications are, by a factor of 3.8, currently cheaper to operate than direct grid-electric systems. Using heat pumps can offset 25-35% of those energy costs, but this still leaves a considerable excess operating charge because of the need to provide top-up energy for safe operating temperatures. Historically, additional system top-up was provided by electric immersions, which for backup purposes and occasional peaks in demand whilst more expensive was acceptable. The shift to fully electric systems has put a greater onus on the technology which was never designed to provide primary heat. The costs are excessive and as we indicated, should they be deployed hard water, can rapidly develop scale leading to permanent damage in a remarkably short time. For this reason, we recommend the replacement of immersion technology with smaller electric boilers that are both more efficient, and, because they operate in a closed loop will avoid the issues of systems scaling up.

Perhaps the most detrimental issue we see today as a result of replacing gas with electricity is the propensity to oversize the new all electric system, replacing gas appliances with electric alternatives with like-for-like capabilities. Hot water systems have been inherently oversized in the past through a lack of understanding of application design or concerns over providing suitable backup to ensure system continuity. The result of oversizing is however always the same, unnecessary capital costs for system supply and installation, but when replacing gas with electricity, oversizing leads to greater electrical demand and should that exceed a building’s available amperage of electrical supply, project installation costs will inevitably soar, or even stall the project.

This can best be avoided by understanding your building’s actual hot water demands and designing the replacement to meet those specific needs. There is an art to designing hot water systems, but real, actionable data is priceless. When considering options for introducing sustainability the best advice we can give is to understand your needs first. Live metering is an easy, non-intrusive way of securing the valuable operational data you need to make informed decisions that deliver on expectations to lower carbon emissions without incurring unforeseen costs.

 

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Sustainability & Water Heating

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In this three-part series on sustainability & water heating, Adveco considers the choices available to commercial organisations that wish to advance decarbonisation strategies in their buildings through the implementation of more sustainable hot water.  

In this first part we consider some of the basic constraints of designing water heating applications, the technology available and the role of air source heat pumps…

Which Path Is Right For Commercial Properties?

Estimates vary, but it is generally accepted that buildings are responsible for as much as 50% of the nation’s carbon emissions, with much of the existing building stock still dependent on gas, which, while increasingly efficient to use is a ‘dirty’ fossil fuel. Daily hot water usage can potentially account for as much as 30% of a commercial building’s daily energy demands so is a notable component of an organisation’s emissions. So sustainability & water heating go hand in hand, and the latter should be one of the first considerations within a decarbonisation strategy.

The relatively lower cost of gas compared to grid electricity, and the necessary high working flow temperatures it delivers have therefore made it historically the energy of choice. This becomes problematic if sustainable operations are now the goal. As a matter of course, new builds, unless exhibiting large demands for gas, will struggle to receive permission (under Part L of the building regulations) for a new gas connection and as a result, are going ‘all electric’ for heating and hot water. With modern construction fabric and insulation, this approach can pay dividends. For legacy properties requiring refurbishment, the choices become more problematic, especially for space heating where modern low-temperature systems need replacement pipework and heat emitters or will fail to deliver. Though this is not an issue for replacement hot water, the complexity of both new build and refurbishment can still suffer costly pitfalls in the drive to sustainability. With electricity on average currently costing as much as 3.8 times that of gas, serious consideration needs to be given to a selection of technologies available to ensure that any changes to a hot water system balance the carbon reduction with the capital and operational costs.

The Options For Sustainable Water Heating

There are several options when it comes to implementing a hot water system and as we have intimated some are driven by finance others by the desire to be environmentally aware. Other factors though can include everything from geology to available space. A building’s location will instantly direct certain decisions as the hardness or softness of the water will impact options. For instance, stainless steel cylinders will be preferential in soft water areas as they are resistant to the corrosive nature of the water, whilst lower-cost glass-lined vessels are preferable in harder water areas. However, high-intensity heating, such as delivered by electric immersion can be extremely detrimental in hard water regions, accelerating limescale generation to the point that it can irreparably damage a system in a matter of months if not correctly maintained.

That does not preclude electricity as a choice, but it does affect how applications should be designed. The real leading question is do you choose gas or electricity? If gas, do you opt for direct or indirect heating systems or if electricity do you choose immersion or electric boiler as your source of thermal energy? Whichever route you decide upon, your system will additionally require a low-carbon heat source which will preheat the water reducing the energy consumption of the water heater, and in turn, reduce carbon emissions and the running costs of the water heater.

There are several choices for securing low carbon heat, including biomass; combined heat and power (CHP); ground or water source heat pumps; air source heat pumps (ASHP), solar photovoltaics (PV) and solar thermal.  Through a mix of cost and simplicity, the best technologies to use for domestic hot water (DHW) systems are either ASHP or solar thermal.

Heat pumps are a technology that operates most efficiently at lower temperatures, making it highly applicable to domestic applications, but commercial DHW systems require 60°C working flow for safe operation and anti-legionella processes. The heat pump can be pushed to deliver a higher percentage contribution, generating temperatures of 45-50°C for preheat, but this at the cost of performance efficiency, requires electrical energy, and that has operating cost implications. Compared to an equivalent-sized direct-electric (ie, from the grid) system, one with an ASHP can achieve carbon reductions of 42-47%, whilst saving 25-35% of the energy costs. The system will still be required to top up heat to the necessary 60°C, using either immersion or an electric boiler. This, combined with the heat pump’s reduced operational efficiency means it will still be much more expensive to run than an equivalent-sized gas-fired system based on a modern and efficient (109% net) water heater.

The recommendation, in this case, is to keep electrical demand down by increasing the size of the hot water storage which is then heated more slowly. This is very different to the high energy input, low storage seen with gas-fired systems. A 30kW energy source can heat 750 litres/hour by 34°C, so when the system draws hot water at a faster rate than it can be heated to 44°C for hot showers you start to get complaints that the water is ‘cold’. The larger volume cylinder helps to overcome this undersizing allowing for a two-hour reheat cycle that maintains enough water at 60°C to meet daily demand, whilst slowly heating reserves through the night when demand is minimal to meet the morning peak.

Despite gaining improved sustainability & water heating modernisation the carbon savings and costs no longer align.

Even with an ASHP operating at optimum efficiency (for 35% recorded reduction in energy) costs would be close to three times that of gas alone, so it is inherently important to consider the nominal value of the carbon reduction when planning a refurbishment from gas to electricity.

However, we can still take advantage of solar thermal which can be employed to offset energy use in gas-fired systems as well as offsetting costs in electric/ASHP applications.

We will discuss this further in part 2

Healthcare Sustainability

Healthcare Sustainability

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Recent research by the University of Exeter sets out the scale of the challenge the NHS faces if it is to achieve healthcare sustainability targets set under the government’s net zero plan by 2040, a full decade ahead of the wider commercial sector.

With a calculated carbon footprint equivalent to 31 million tonnes of CO2, 62% of which can be attributed to its wider supply chain, the NHS must reduce emissions by 8% each year through until 2036.

This means stakeholders across government, NHS and industry need to be working together in order to provide new standards for procurement and innovation to ensure sustainable practices.  One area that accounts for a consistent and definitive need within the NHS is the provision of hot water. A core facet of hygienic working practices and the provision of healthy spaces for treatment and care, heating water can be an energy-intensive process, accounting for as much as 30% of daily energy demands. It is also a provision that can immediately deliver a reduction in carbon emissions and operational costs once implemented, whether a building is new construction, or more likely a refurbishment of existing property within the NHS estates,

For more sustainable domestic hot water (DHW) systems, we expect healthcare facilities will look for hot water to be generated at a commercial scale via multiple localised systems that each provide hot water to wash hand basins and showers for a dedicated area. This has been the most common use case seen across recent pandemic-driven refurbishments for example. This typically will see systems arranged on a ward-by-ward basis, but appliances may also supply hot water to local shared spaces where appropriate. Such systems will demand hot water be stored and distributed at a minimum temperature of 60°C. Working flows could be required up to 75°C with minimum return temperatures not below 50°C.

The overriding issue is that NHS health technical memoranda (HTM) 04-01* states that, preheat vessels cannot be used unless they can be guaranteed to preheat to a minimum of 45°C. This could immediately preclude for instance the use of solar thermal as a lone source for preheat. However, it matches well to the minimum working flow temperature for preheat that we would design into a system utilising the current generation of air source heat pump. Solar thermal would be more effective for the provision of top-up heating. Awareness of this facet of the HTM has historically been either ignored or missed, so solar thermal has been deployed in a number of health facilities, often successfully, and Adveco has been servicing hospital solar systems for more than a decade in such locations as Merseyside and Greater Manchester. That said, we are aware of systems that have not met the requirements of the HTM leading to costly decommissioning.

To achieve net zero and meet NHS mandates for DHW a typical sustainable application would see hot water generated via a pair of parallel-arranged hot water cylinders to ensure redundancy. These would be sized to provide 60% of the hot water demand for the area served based on a peak 15-minute duration loading. The heat into the cylinder would come from a combination of solar thermal collectors and an air source heat pump working in conjunction to guarantee the preheat temperature

The design of the system allows for the heat pump to contribute to the incoming cold water.  That ensures 45°C while taking full advantage of the COP of the heat pump.  The solar thermal is employed after the heat pump to heat the water from 45°to 50 or 60°C depending on the time of year. We calculate the solar contribution over the year, with a system able to provide about 10% of the peak output when conditions are at their worst – short days with low sun and heavy cloud cover – rising to 30% under optimal conditions.

Should temperatures of up to 75°C be required, a high-temperature electric heat source would be used. Whilst typically an immersion, we would suggest specifying an electric boiler to avoid issues of scale in hard water areas, also well as delivering further system redundancy since the boiler will incorporate multiple immersions within its chassis. The electric boiler tops up what the solar could not manage. Still, by delivering preheat through both the ASHP and solar thermal system, demands on more costly electric heating are considerably reduced, if not avoided entirely. While higher temperatures will reduce solar efficiency, it is still useful to offset the high-grade heat than the low-grade/high COP heat pump heat and help to deliver on healthcare sustainability targets.

Example three-cylinder arrangement to meet healthcare sustainability and NHS HTM.  The heat pump and solar use a dual coil cylinder with the heat pump on the bottom and the solar on top. With this arrangement, there is no thermal conflict between the heat pump and solar adds what it can. 

The entire tank is heated to 45C by the heat pump and then receives solar top-up. A purge pump would run once per day to use the after heater to heat up the preheater for sterilisation to prevent legionella.

*Reference link https://www.england.nhs.uk/publication/safe-water-in-healthcare-premises-htm-04-01/

Adveco AD Wall-Mounted Water Heaters For Commercial Properties

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  • A range of three compact commercial semi-instantaneous gas condensing water heaters
  • Perfect for applications requiring direct contact with soft and softened water
  • Compact and smart for no-nonsense installation and maintenance

Commercial hot water specialist Adveco, announces the Adveco AD range of high-efficiency condensing gas-fired wall-mounted water heaters. Designed to provide a compact, high capacity and reliable method for delivering instantaneous hot water to a building, the new range consists of three models, the AD16 (27kW rated heat output), AD22 (33 kW) and AD37 (61 kW).

The AD is a range of ‘A’ class energy-efficient wall-mounted water heaters, with a net efficiency of up to 107% for the production of domestic hot water (DHW). With an efficient pre-mix burner and minimal NOₓ and CO emissions, the AD range is an eco-friendly way to serve a DHW system. Featuring a high 1:8 modulation ratio, wall-mounted ADs ensure maximum efficiency even during periods of low demand.

The wall-mounted water heater features a single high-quality patented heat exchanger constructed from a continuous, non-welded run of  AISI 316Ti titanium-stabi­lised stainless steel, providing exceptional construction strength and corrosion resistance. The brand-exclusive three-pass design features large bore, circular tube cross-sections that reduce the collection of debris.

Bill Sinclair, technical director, Adveco said, “For property renovation where space is at a premium or when existing gas appliances need modernising, the AD wall-mounted water heaters range delivers highly efficient operation in a compact form factor. The titanium-stabilised stainless-steel construction of the AD’s heat exchangers is also the perfect response to counter the concerns of corrosion in soft or softened water applications.”

Also included is an inbuilt controller with an LCD display that ensures full temperature control and a maintenance self-check of primary components and functions.

Additional Information

  • Compact wall-hung arrangement
  • High-efficiency pre-mix burner provides a large modulation range
  • Ultra-low NOₓ emissions at 16-29 mg/kWh
  • Available using natural gas or LPG
  • Supports standard concentric or parallel flue systems using an adaptor for low-cost 80/125 mm diameter PP available on request
  • Integrated run/fault signal for connection to BMS
building sustainability into commercial hot water DHW

Building Sustainability Into Commercial DHW

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For more than fifty years, Adveco has been a leading innovator providing domestic hot water (DHW) applications for commercial-scale projects across the UK. Today its focus is shifting to encompass a blend of traditional and new, more renewable technologies in the form of solar thermal and especially heat pumps building sustainability into commercial DHW systems.

With a predicted one-third rise in non-domestic floor space by 2050, much of the current focus resides on new builds, but this still leaves more than 1.6 million pre-existing non-domestic buildings in England and Wales, generating almost one-fifth of the UK’s carbon emissions, needing expert, practical support.

Air source heat pumps (ASHP) have become the poster child technology for the government’s net zero strategy and therefore a core tool for building sustainability into commercial DHW systems.  The advantage of ASHPs is that, with performance greater than 100%, they can extract additional energy from outside of the building’s metered systems delivering significant carbon savings. For a commercial DHW system, it is recommended that a working water temperature from the ASHP, such as Adveco’s FPi32 or L70, must be at least 55°C. This is certainly attainable from current generation ASHPs when deployed in a hybrid approach. This uses the ASHP as preheat and combines it with either gas-fired or more preferably an electric top-up to achieve the required hot water temperature. This is where the additional system complexity and cost can creep in. But by correctly balancing a system through a mix of physical spacing in the vessel and system monitoring with dedicated controls, as developed for the Adveco FUSION, the system no longer fights itself, working seamlessly to deliver the highest operational efficiencies

In line with the European Commission’s proposal for a tightening of F-Gas regulations, development work continues at pace to support the introduction of R290, or propane as it is more commonly known. This refrigerant offers a coefficient of performance (COP) that enables working flow temperatures from an ASHP of up to 75°C and potentially much higher. This means future commercial systems can be less complex, without the need for additional electric immersion for high-temperature top-up and flushing for legionella protection. That said, immersions remain perfectly suitable for low-demand backup applications in boiler-fed indirect cylinders, ensuring business-critical DHW demands are met.

What we have seen more recently though is a shift in use, where immersions are used ‘directly’ in high-demand commercial applications as the primary heat source. An electric immersion heater has a high heat intensity compared to gas or indirect and, when coupled with high operating temperatures and hard water will increase the rate of scale formation which, over time, will cause the element to rupture.

In response, protecting a system from limescale is often only addressed by a vigorous cleaning regime. This method has a cost and downtime associated with it that is not acceptable for many commercial buildings.  For this reason, minimisation of scale formation with a water softener or a scale inhibitor may be adopted, but for many sites neither provides a satisfactory response because of space, maintenance, downtime, or cost.  A better option for these sites would be to replace the immersion heaters with a low-scale forming hot water system.

The new Adveco ARDENT electric boiler range provides a proven and cost-effective answer. Electric boilers still utilise immersion heaters located in a small tank heat exchanger within the boiler housing. This electric boiler supplies a sealed ‘primary’ loop to an indirect coil in the cylinder. The electric boiler heats the same water continuously so there is only a finite amount of scale in the system which will not damage the elements. The heat exchanger in the cylinder is a large coil operating at relatively low temperatures. Adveco’s extensive experience with indirect coil use in the UK has shown that scale is not a significant problem in these systems. The electric boiler operates at the same efficiency as an electric immersion heater (100%) so the only overall difference in system efficiency is the minimal pump electrical consumption and a small amount of heat loss in the pipework.

An electric boiler hot water system will take up a little more space than an all-in-one electric cylinder, but it has more versatility and requires less clearance for the cylinder. Similarly priced to an immersion heater, an electric boiler-based system will cost slightly more due to the small amount of additional installation work. But with virtually no maintenance and the cylinder forming significantly less scale, vastly improving reliability, the operational and maintenance savings will offset these additional capital costs. The electric boiler additionally offers a level of redundancy that is not achieved with a single immersion heater.

As the limitation on new gas grid connections for heating systems becomes effective this year, it will become critical for system longevity to recognise the new challenges electric-only presents over more familiar gas-based applications. If a business already uses gas, then it can still upgrade to new gas appliances until 2035, with 100% hydrogen-ready options extending that window well into the 2040s based on current appliance lifespan.

Adveco continues to support the refurbishment of existing buildings, recently extending its ranges of direct-fired condensing water heaters – the AD and the ADplus. Both ranges provide a compact, floor-standing design that is easy to introduce into an existing plant room to provide high-demand semi-instantaneous and instantaneous hot water applications.  Improved combustion efficiency means the burner requires less gas, delivering up to 30% savings in fuel consumption, making it more cost-effective, while reducing emissions.  For smaller on-demand needs, ADplus heats only what is necessary, with no ignition for smaller withdrawals providing considerable additional energy savings. Both AD and ADplus as a result exhibit ultra-low NOX (Class 6 appliance at 27 mg/kWh) and CO emissions (19ppm). With the government already committed to enabling the blending of hydrogen in the gas grid, it is also worth noting that these latest generation direct-fired condensing water heaters will already support the initial 20% hydrogen/natural gas blend.

Together, these technologies offer actual development arcs right now for existing commercial properties that are currently on gas, or new builds seeking to embrace low or no emission choices building sustainability into commercial DHW systems for more environmentally friendly operations that will help organisations achieve net zero by 2050.