The trend towards smaller commercial boilers
Small commercial boilers, such as Potterton Commercial’s Paramount two range with outputs from 30 to 115 kW are finding increasing application.
10 years ago, wall-hung boilers above 100 kW would have been almost unthinkable, but now they are commonplace in commercial heating installations. Richard Walker explains how the market is changing to embrace smaller boilers in light-commercial applications.Over the last decade, building-services specifiers have been under increasing pressure to keep non-revenue generating areas in a building to a minimum. Rising property prices and the escalating cost of commercial space has signalled the end of the road for traditional large atmospheric boilers in an equally expansive plant room. Space is at a premium, and we all need to be thinking smaller to ensure we achieve space efficiency as well as energy efficiency. Market demand
For manufacturers, the move towards smaller boilers has been driven by market demand and legislative changes. Following the publication of the latest Part L Building Regulations, the move to high efficiency has catalysed the design of small commercial boilers with higher outputs, as inherently condensing technology is more compact than traditional pressure jet or atmospheric variants. In addition many manufacturers are adding boilers with smaller outputs to their commercial ranges as building insulation improves and the demand for heat, even in large premises, decreases. The growth in demand for smaller-output boilers can also be attributed to an increase in renewable products for the commercial sector. Solar thermal heating, biomass boilers and heat pumps can provide water and, in some cases, space heating for a building. With heat being generated by these renewable sources, traditional gas or oil fired boilers will be used as a complementary heat source — as electric immersion heaters are in domestic properties. Research into materials, manufacturing and design continues to ensure that commercial boilers are now made to be lighter, more compact and offer modular formations in a relatively small or tight space, often built into prefabricated package solutions. For refurbishment projects, some floor-standing condensing units are perfect replacements for atmospheric boilers as they offer a smaller footprint and do not require major changes to pipework. For new builds, many specifiers are opting for wall-hung boilers which are compact and as powerful as their floor-standing counterparts and need only a small plant room. Small-output boilers are also recommended for commercial extensions. When the heating system in a building is running to full capacity, it will not be possible for the additional space heating requirement to be matched by the existing boiler installation. Rather than overload or replace the system, a more cost-effective solution is to add another boiler to match the heat load to the extension. A typical example would be a school where more classrooms have been built. Temptation
One problem arising from the demand for smaller boilers, is the misguided temptation for specifiers to opt for a large domestic boiler over a commercial model for applications with a low heat load, such as a health centre or small business unit. However, in most cases this would be a mistake because there are distinct differences between commercial and domestic boilers, as they have been designed and built to function very differently. The main difference is the controls, which on a commercial boiler will be capable of weather compensation, zone control and optimised start and stop. The basic controls on a domestic boiler would not be suitable for a functional light-commercial building and the demands of its users. Recognising the demand for compact lightweight designs, Potterton Commercial has a range of compact heating solutions for commercial applications. The Paramount two range of wall-hung boilers has been recently extended to include 95 and 115 kW models. The range now comprises six models with outputs from 30 to 115 kW. These boilers have a net efficiency of up to 109%, so they comply with Part L2 of the Building Regulations and are included on the Energy Technology List. Potterton Commercial has pre-empted the step change in thinking to small boilers for commercial applications and will continue to support specifiers through the provision of a range of boilers suitable for all commercial premises in the future. The commercial market has come a long way in 10 years, and we predict that there are more changes ahead; boilers are set to get even smaller, lighter and more efficient as technology advances, creating more choice for the commercial specifier. Richard Walker is national sales manager with Potterton Commercial.