Energy system modernisa­tion

Lämpöjokeri installed air-to-water heat pumps in an industrial building in Lahti to decrease the property’s energy costs.


In Vartiolaakso, Lahti, a group of five different industrial buildings had previously been heated entirely by natural gas. Rising energy prices underlined the need to renovate the system. Lämpöjokeri, an experienced contractor specialising in heat pumps was commissioned to carry out the modification. Lämpöjokeri installs around 1000 heat pumps per year in various locations.

Air-to-water heat pumps are a very viable solution for reducing the running costs of a system previously based on natural gas alone. Even in a large building, the investment budget remains moderate if the whole system is not renewed at once. The payback time is also relatively short when switching to on-board connection.

The five buildings in Vartiolaakso accommodate a variety of businesses, including a car dealership. The buildings are approximately 25 years old and their size ranges from 500 to 2,000 m2. All buildings are equipped with water heating systems and were originally fueled by natural gas.

– We installed air-to-water heat pumps in each of the five properties. There are seven machines in total, as the two largest ones have a combined capacity of around 50 kW. The indoor units of the air-to-water heat pumps are now connected to the properties’ water heating system, says Jussi Heimonen, Managing Director of Lämpöjokeri.

The installation team must understand the building’s technology and systems thoroughly. Otherwise even small mistakes can have a big effect

Jussi Heimonen, Managing Director, Lämpöjokeri

– However, another source of energy is still needed, as the pumps’ power output decreases in extreme cold (-20 C), while the heat demand increases accordingly. These are exceptional situations to which the system automation reacts. Nevertheless, around 90% of the heating energy is produced by heat pumps. This has a major impact on the overall annual costs.

Skilled technicians ensure a successful installation

Knowledge is especially needed in renovation projects because each project is unique. When the automation is different, the method of heat distribution varies and the documents of the original plan or the values ​​used as a basis are not available, the installation company’s professional expertise is vitally important.

– The installation team must understand the building’s technology and systems thoroughly. Otherwise even small mistakes can have a big effect – and, as a result, the system does not work correctly and does not achieve the desired savings, Heimonen reminds.

Lämpöjokeri also makes installations on facades, and Jussi Heimonen is proud of his team. Quality control is very detailed, and each work phase is described in Lämpöjokeri’s internal system.

– Our work may take a bit more time than an average installation, but we are always more accurate. Over the years, we have received praise from our customers for the quality of our work.



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