Solving complex ventilation challenges with bespoke AHUs Posted on 29/09/202629/09/2026 by avt_admin No two ventilation projects are exactly the same. Buildings vary in size, layout, and purpose. Available plant space differs dramatically. And there is huge variability in access restrictions, performance requirements, and client specifications. Despite this, standard air handling units (AHU) designed around predetermined dimensions and configurations can still often provide everything required. But when a building presents a particularly unusual challenge, or clients have especially specific performance needs, bespoke AHUs might be the only feasible solution. Challenges that influence AHU design Several considerations have to be balanced for every successful AHU installation. Bespoke AHUs are normally a response to a small number of consistent challenges, including: Restricted space. A refurbishment project, for example, may have very little available plant space. Existing walls, ductwork, and other building services can limit the dimensions of a new AHU. Access limitations. If access routes are narrow, standard AHUs may be unable to be either delivered, positioned, or installed correctly. Performance requirements. Airflow, heating, filtration, and extract requirements can all be specific to the building, with some environments demanding higher performance than standard AHUs deliver. Air Vent Technology has a long history of designing and manufacturing bespoke AHU units that meet the performance, space, installation, and operational demands of clients across the UK. It’s from these decades of experience that we know bespoke design gives engineers greater freedom to balance any competing requirements. Making an AHU fit a confined space A previous AVT project demonstrates just how important this flexibility can be. Our customer needed a supply AHU small enough to travel through the building, be installed inside an existing enclosed cupboard, and meet specified airflow, filtration, and heating requirements. The cupboard couldn’t be rebuilt or dismantled, creating strict limits on the dimensions of the unit. Over a three-month period, we worked with the customer to refine the design. The eventual solution used a U-shaped airflow arrangement, with air travelling down through the unit and back up. This allowed the AHU to fit the available space while delivering the required 400l/s airflow and a 20°C temperature rise. Planning extended beyond the AHU itself. Doors, corridors, and other potential obstacles were measured to confirm that the completed unit could reach its final position. The result was a bespoke AHU that met the required performance specification within a highly restrictive space. When the specification goes beyond performance For another bespoke project, we supplied a colour-matched externally mounted AHU for a new biomethane production plant. The unit needed to provide tempered air, with a high-level extract fan supporting crossflow ventilation. Its position on an elevated external platform meant custom sizing was required. The customer also wanted the equipment to maintain visual consistency with the rest of the plant. Our expertise ensured the unit was manufactured in the exact RAL colour requested, using powder-coating capabilities to achieve the required finish. From the initial site visit to delivery of the finished unit, the entire process took just two weeks. The completed AHU met its performance targets, fitted the designated space, and matched the customer’s required colour. Bespoke AHUs: start the conversation early Both projects highlight the value of involving an AHU manufacturer as soon as possible when unusual requirements are identified. Early discussions allow engineers to understand the complete picture and consider requirements together rather than individually. Potential problems can also be identified and resolved before any equipment reaches site. As bespoke AHUs continue to play an important role across refurbishment, retrofit, and new-build projects, the starting point is always the same: understanding what the project needs and designing the AHU accordingly. If you’re working on a project where space, access, or unusual performance requirements are making AHU selection difficult, speak to our team about a bespoke solution. We’re always ready to help.
The Sustainability Benefits of Refurbishing Existing Ventilation Equipment Posted on 28/08/202628/08/2026 by avt_admin As your ventilation system reaches the later stages of its working life, replacement can seem like the obvious choice. Improved efficiency, modern controls, and updated components all make new air handling units (AHUs) look attractive. But replacing old equipment also has a significant environmental cost. And it’s this cost that can be the key issue when you’re trying to decide the most sustainable route forward. In the right circumstances, and with the supporting calculations to prove it, choosing to refurbish existing ventilation equipment can result in reduced waste and lower levels of embodied carbon compared to installing a new unit. Making sure you have a basic understanding of embodied carbon is the first step in your decision. What is embodied carbon? Ask most people about the carbon impact of their HVAC unit, and they’ll tend to think about how much energy is used when the machine is turned on. Less obvious, though, are the greenhouse gas emissions associated with the equipment throughout its life. CIBSE’s TM65 methodology considers emissions linked to manufacture, installation, maintenance, repair, replacement, and end of life. For ventilation equipment, these ‘unseen’ greenhouse gases can be significant. Large units often contain substantial quantities of steel, aluminium, and iron, all of which have an associated carbon footprint. So while a new unit might use less energy when it’s running, its environmental impact began long before it was ever switched on. The full environmental cost of replacing HVAC units Replacing an existing AHU also involves more than manufacturing a new unit. Consider also the greenhouses gases used in its transportation to site, the dismantling and removal of the old unit, and the installation, connection, and commissioning of the new unit. Any associated construction work, like modifications to ductwork or electrical systems, also come with their own environmental cost. None of this means replacing old equipment is always the wrong sustainability choice. It’s just that both sides of the equation should be considered. Extending the life and performance of HVAC equipment Refurbishment is the single biggest thing you can do to improve both the lifespan and the ongoing performance of your existing AHU. From minor tasks, like replacing worn or inefficient components, through to upgrading fans and motors or repairing damaged sections, the amount of refurbishment needed depends on the AHU’s current condition. Even relatively small but targeted improvements can improve both the reliability and performance of an existing AHU. This also means fewer waste materials, with the majority of an existing unit staying in place and only specific elements being replaced. CIBSE’s guidance on existing building services highlights the importance of considering restoration and retrofit alongside replacement. It also offers a starting point for embodied carbon calculations. This helps you to better identify, given the importance of whole-life performance, whether refurbishment or replacement is the greener option for your specific circumstances. Refurbishment as part of a wider sustainability strategy Existing buildings will play a major role in reducing carbon emissions, which means retrofits and refurbishments are set to become more prominent than ever. But they’re not always the right approach. Sometimes, installing from new is the only sensible way forward. A comprehensive sustainability strategy recognises these two options can co-exist, even within the same building. What’s key is the best whole-life outcome, rather than the option that best aligns with a belief rather than an evidence-backed case. Good sustainability strategies also look at a series of other initiatives: reducing unnecessary energy use, improving controls, and maintaining equipment properly can all contribute to better building performance. Refurb or replace? Our experts are ready to help Before committing to a full replacement, it’s worth assessing whether your existing ventilation equipment has useful life remaining. Air Vent Technology can assess existing systems and advise on potential refurbishment or replacement options, helping you understand whether upgrading or replacing your equipment is the most appropriate route. Contact us today. We’ll be happy to help!
Is your building ready for the next heatwave? Posted on 27/07/202627/07/2026 by avt_admin There’s no doubt about it: British summers are getting hotter. And when temperatures rise, ventilation systems are put to the ultimate test. Reliable air movement and temperature control become the central focus for facilities teams working to ensure healthy, productive indoor environments. But in any UK heatwave, ventilation systems operate markedly differently to the rest of the year. Components that have seen little use during cooler months may suddenly be required to operate continuously, exposing issues that have previously gone unnoticed. For facilities and building managers, this makes summer an ideal time to review system performance and ensure everything is operating as intended. The cost of waiting for something to go wrong Many ventilation issues develop gradually. A blocked coil, worn component, or poorly calibrated control system might not create noticeable problems during milder weather. However, once temperatures rise and demand peaks, small faults can soon affect system performance. Buildings with high occupancy or large glazed areas can feel the effects particularly quickly. But by then, urgent repairs, increased costs and operational disruption can be inevitable. Preventative maintenance, which includes checks and tests before these issues occur, is almost always more cost-effective than responding after a breakdown. The importance of regular servicing and inspections Routine servicing gives facilities managers a clearer picture of how their ventilation systems are performing before seasonal demand increases. By regularly working to check controls, identify worn components, and ensure cooling functions are performing efficiently, any developing issues can be spotted and resolved before they turn into larger problems. This proactive approach helps to extend equipment life, improve energy efficiency, increase system longevity, and maintain occupant comfort throughout the warmer months. For buildings and facilities managers, one result above all is invaluable: ongoing confidence that your ventilation system is ready when it’s needed most. The flexibility of bespoke STP and STR air handling units If you’re looking to make significant upgrades in your ability to keep cool this summer, our flexible and custom-built STP and STR air handling units could be the key to your building’s ongoing comfort. Every site presents different challenges, so our units are designed around individual project requirements rather than fixed, standard specifications. Plantroom or rooftop versions are available, each with the ability to incorporate cooling coils and additional components where necessary, and they can be used both for new installations or refurbishment projects. This enhanced flexibility – much greater than standard off-the-shelf options – allows facilities managers to invest in solutions tailored to their building today, while retaining the ability to accommodate future operational changes. Talk to Air Vent Technology Whether you need planned maintenance support, advice on system upgrades or a bespoke STP or STR air handling unit designed around your building’s requirements, our team is ready to help. Get in touch to discuss your project and ensure your ventilation system is ready for whatever the summer brings.
5 signs your ventilation systems needs refurbishment or repair Posted on 24/03/202624/03/2026 by Ella Walker Across the UK, rising energy costs rise are putting businesses under even greater financial strain. But it isn’t just global events that are impacting bills. Poorly maintained or inefficient HVAC systems can also lead to wasted cash. Ventilation systems that are working harder, but delivering less, are common in factories, warehouses, and other commercial settings. Unfortunately, HVAC maintenance is often overlooked… until something goes wrong. But by the time a system fails, you’ve usually already been paying the price in higher bills, poor performance, lower air quality, and increased noise. Here are five clear signs your ventilation system may need refurbishment or repair, and why acting early matters more than ever. 1. Rising energy bills If your energy costs are rising faster than your energy unit rates, your ventilation system could be a major contributor. Over time, key components such as fans, motors, and control systems lose efficiency. As performance drops, systems have to work harder to deliver the same level of airflow. That increased workload directly translates into higher energy consumption and, in turn, that means higher operational costs. But a good refurbishment can use upgraded components to restore some of that lost efficiency, helping bring those costs back under control. 2. Increased noise or vibration A well-functioning ventilation system should operate smoothly and relatively quietly. If things are starting to rattle or shake, it’s often a sign that something isn’t right. An experienced refurbishment engineer will take time to check for worn bearings, loose components, ageing fan motors, and imbalanced fans. If any of these faults are left unchecked, they can lead to more serious mechanical failures – and potentially costly downtime. Getting an expert in early can resolve small issues before they become something much more challenging. 3. Poor or inconsistent airflow Inconsistent airflow is one of the most noticeable and disruptive signs of a struggling system. If you’re experiencing hot or cold spots across your facility, areas with poor ventilation, or even just a general decline in indoor air quality, it could be time to get your system checked. A thorough repair or refurbishment can restore balanced airflow and improve overall system performance, without the cost of a full replacement. 4. Frequent breakdowns or rising maintenance costs If your maintenance team is being called out more often, or repair costs are steadily increasing, it’s a clear warning sign that a full refurbishment might be the most cost-effective way forward (sometimes cutting costs by up to 50%). As ventilation systems age, components fail more frequently, repairs become more regular, and maintenance costs begin to stack up. But at a certain point, investing in refurbishment is simply cheaper than continuing to patch up an ageing system. Taking a proactive approach, and making that decision early, can reduce unplanned downtime and bring long-term savings. 5. Your system is 10–15+ years old Many commercial ventilation systems are built to last, but that doesn’t mean they stay efficient forever. Even if the structure of the system is still sound, internal components can become outdated and inefficient. Refurbishment offers a smarter alternative to full replacement, allowing you to upgrade key elements like fans, control systems, and filtration. It also provides an opportunity to install the most energy-efficient components. This approach modernises performance without the cost and disruption of installing a completely new system. The benefits of refurbishment Refurbishing or repairing your ventilation system helps to improve performance in a range of areas. From lower energy consumption and reduced running costs through to improved indoor air quality and extended system lifespans, repairs and refurbishment have been proven to deliver the best balance between cost and performance. They also offer far less disruption than a full HVAC system replacement. The key is to act before problems escalate. Ventilation issues rarely fix themselves, and waiting too long can turn a manageable upgrade into a costly emergency. If you’ve noticed any of these five signs, now is the time to act. Contact our servicing specialists to start future-proofing your system and put your business in the best possible position.
Top Marks for Classroom Ventilation: Introducing the Infinity® ClassFlo® CF350 Posted on 21/08/202504/11/2025 by Ella Walker Our latest decentralised heat recovery unit for classrooms, the Infinity® ClassFlo® CF350, has now officially launched – allowing schools nationwide to immediately create healthier, quieter, and more efficient learning spaces. Purpose-built for education settings, this unit combines high-performance engineering with intelligent control to deliver cleaner air, lower energy bills, and quieter learning environments. Whether your school is planning maintenance during the next half- or full-term break, or wants to upgrade as soon as possible, the CF350 is available now and primed to make an instant difference. The benefits of the Infinity® ClassFlo® CF350 From mainstream classrooms to special educational needs (SEN) environments, the CF350 is tailored to meet the complex needs of modern education settings. It meets the latest standards for school ventilation and building performance, including BB101, BB93, Approved Document F, and Approved Document L. So excellent indoor air quality, thermal comfort, and sustainability are all guaranteed. This system provides 100% fresh, filtered air with no recirculation or mixing, helping keep classroom CO₂ levels below the recommended daily average of 1,000 ppm. For pupils, this translates into better concentration, less fatigue, and more productive learning environments. Understanding the full tech specs The CF350 is a high efficiency counterflow heat exchanger available in above ceiling and below ceiling configurations with either left- or right-hand access. Installation is straightforward, with top and bottom access for maintenance and most sensors housed within the unit itself to reduce additional setup costs. Once installed, intelligent controls make operation a breeze. Remote access via Bluetooth or NFC means no specialist tools are required. The unit also integrates with building management systems via Modbus, with BACnet compatibility available on request. Once in place and fully operational, each CF350 unit: Recovers up to 88% of heat, reducing the need for additional heating or cooling Uses up to 52% less classroom energy compared to low-efficiency or hybrid systems Delivers up to 78% greater energy efficiency Offers full heat recovery with consistent temperatures and ventilation, even during winter and summer peaks Meets the 30 dB(A) requirement for SEN sensory spaces, vital for pupils with auditory sensitivities or hearing impairments. Ensures noise stays low via a double-skinned construction with acoustic insulation Supports respiratory health and school attendance with high-efficiency F7 and M5 filters removing pollutants, allergens and fine particles from the air Optimises comfort with four seasonal operating modes, including heat exchange and free cooling The CF350: ready when you are Whether you’re upgrading a single classroom or planning a site-wide rollout, the CF350 can be installed with minimal disruption. If your school also needs ventilation solutions for kitchens, toilets, shower areas or communal spaces, Air Vent Technology has a full range of systems to support your project. Download the Infinity ClassFlo CF350 brochure today and get in touch to discuss your next steps.
