The benefits of modern modular boilers in plant room design

Up until recent years, large traditional floor standing boilers have been the go-to solution for buildings requiring high heat output. However, as floor space becomes a valuable commodity, manufacturers have responded by providing a range of boilers that offer unprecedented flexibility in system design. Here, we look at the benefits of modular boilers and highlight how they can help to provide a flexible and space-saving solution for modern plant rooms, without compromising on power.

What is a modular boiler?

Modular boilers are designed as an alternative to large single boilers and offer an efficient, secure and flexible approach to commercial heating. Essentially comprising a number of separate small boiler modules, which can be installed alongside one another in a horizontal or as a vertical stack, modulation is shared across all modules in the system to ensure only the required amount of heat is generated. Featuring a space saving design, modular boiler systems are best suited to commercial buildings that need to efficiently make the best use of space.

Space and size in modern plant rooms

Where floor-standing boilers have traditionally been the boiler of choice for projects requiring high heat output, they may not always be the most suitable and practical option. When it comes to retrofits in older buildings, demands may have increased over time, or the building may have had an extension. Herein lies a problem.

Increasing boiler size to adequately meet the changing demands of a building could be an issue for plant rooms where space is already limited. For instance, when construction and refurbishment contractor, Mulalley & Co, needed an efficient and space-saving heating system to replace its seven existing NGR floorstanding cast iron sectional boilers, it upgraded to two Hamworthy Modumax modules, stacked on top of each other, with a total output of 464kW. With the previous system using up most of the floor area available, the new modular system reduced the area needed by nearly half.

Similarly, when it comes to modern commercial buildings, plant room space is often at a premium. With the priority being on floor space that generates value for money, plant rooms are often small and discreetly tucked away, in areas such as basements and rooftops. To address this issue, modern condensing modular boilers can be positioned in a way that best suits a plant rooms layout.

Available as single boiler modules, or with the option to stack in combinations to the desired output (in a horizontal arrangement, or as a vertical stack), continuous product development over the last few decades has made it possible to achieve an output of 1MW with modular boiler systems from less than 1m² of floor space. This means the best use of space can be achieved in even the smallest of plant rooms.

Ease of installation

Compared to larger high output boilers, which may require a crane during the installation process, modular boilers can be easily separated and moved to the place of use within a building. Furthermore, thanks to their compact design, potential issues with access, such as tight stairways, narrow doorways and overhead obstructions can be avoided. It’s also worth remembering that when it comes to retrofits, modular boilers can also be installed alongside the existing boiler. This enables a smooth changeover from the old heating system to new, with little or no system downtime.

High turndown ratios and load matching for increased efficiency

In addition to offering a space-saving alternative, modular boilers also offer high energy efficiency. Unlike traditional boilers that operate at fixed heat outputs, modulating boilers adjust their heat output based on the current demand. This means the boilers deliver the right amount of heat, at the right time, with little or no wastage. This not only has valuable cost benefits but also makes for a low environmental impact.

To understand the full impact of this versatility, let’s consider an application that requires four 70kW non-modulating boilers that can be turned down from 280kW to 70kW in 70kW increments. If there is an off-peak demand period, requiring a constant 95kW of power to maintain a heating circuit at a set temperature, two boilers would need to run together to meet the demand. However, the plant would then produce 140kW, which is 45kW more than necessary. In comparison, three 97kW Modumax mk3 97/291V units could be installed as an alternative to four non-modulating 70kW models; together, at 291kW, these would satisfy the 280kW peak load requirement. However, as boilers run most efficiently at lowest loads, this 95kW requirement could be efficiently achieved by firing two or three Modumax mk3 boilers and modulating these together to achieve the desired power for example, three boilers, each running at 31.6kW each.

Reduced wear and tear

This would also reduce the inefficiencies of short cycling, which can lead to not just energy waste but more worryingly, wear and tear, which could eventually result in boiler breakdown. By adjusting to the heat demand in real time, modulating boilers avoid this problem and provide a constant and efficient heat supply. To further enhance the longevity of modular boilers, it’s also important to specify a product with a stainless-steel heat exchanger. This will offer increased resistance against corrosion. Also, as stainless-steel heat exchangers can withstand a higher flow rate than exchangers made from other materials, the risk of blockages within the exchanger from debris or rust will also be minimized.

System security

Despite all the best will in the world, things can and still do go wrong and this is where modular boilers offer increased protection. With a modular boiler system, there’s the added benefit of system back up. Should one boiler module need servicing or stop working, the other modules in the system can continue to meet the system demand for heat without the risk of interruption to services. This is a particularly important consideration for many commercial facilities, such as schools and healthcare facilities that rely on heating and hot water to be able to operate safely.

A fitting solution

With the constant battle to achieve more with less in today’s world, modular boilers provide a flexible and energy-efficient solution. Designed to accurately match the heat load profile of a building, with minimal risk of costly disruption and unplanned downtime, modern modular boilers offer a durable and cost-effective solution for commercial buildings. Moreover, thanks to their considerably reduced footprint and low CO2 and NOx emissions, they successfully reduce the space needed for equipment in a plantroom, while lowering impact on the environment.

Want to know more?

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