Potterton Commercial has stressed the importance for HVAC contractors to expand their knowledge of energy efficiency, beyond simply adhering to the minimum legal standards.

This follows the results of UK Construction Week’s survey, in which 67% of respondents said that a lack of knowledge prevented the efficient running of buildings.

While knowledge and application of standards required for regulatory compliance, such as ErP are undoubtedly important, they are not the be-all and end-all, says Potterton.

Steven Evans, National Sales Manager at Potterton Commercial, said: “When recommending an energy-efficient boiler, the go-to data is often its seasonal efficiency. But most modern, condensing commercial boilers perform well when it comes to this measurement, so it can be difficult to differentiate between makes and models using this benchmark alone. To get the most accurate picture of a boiler’s overall efficiency, engineers should also consider its modulation range.

“Modulation range is the difference between the maximum and minimum output of a boiler, often expressed as a ratio. For example, Potterton Commercial’s Sirius two boilers have a modulation ratio of 9:1, so its 90kw model can modulate down to 10kw. As a general rule, the higher the ratio, the better. It plays an important role in enabling a building to operate more efficiently.

“Once a room has reached the desired temperature and thermostatic radiator valves are closed, the power demands on the boiler will be considerably lower. If a boiler has a narrow modulation ratio, this means that the minimum output of the boiler will be higher than it needs to be, causing the boiler to constantly switch on and off. This wastes fuel and adds additional wear and tear to components. A wide boiler modulation ratio reduces constant on/off cycling, and can better accommodate fluctuating heating demands without using excessive energy, therefore improving efficiency and extending the life of a boiler.

“For busy contractors, it is easy to concentrate on simply complying with legislation. Energy efficiency is an overall picture comprising many different elements, including season efficiency and modulation ratio. To consider either measure in isolation will not result in the best possible levels of energy performance for a building – which is why contractors should always bear modulation ratio in mind when recommending and installing a new boiler for commercial applications.”