Granloholm

The Granloholm project covers a residential area in Sundsvall, 380 kilometres north of Stockholm, with 30 buildings of various sizes giving home to more than 230 families. These housing buildings were first constructed in 1979 and in 2006 the need for a thorough renovation became apparent.

The customer, TotalFörvaltning AB, specified that the main objective for this renovation project was to increase comfort within the home using more energy efficient systems and equipment, thereby reducing heating costs for all tenants in the development.

The installing company, TF Service AB had successfully worked with IMI Hydronic Engineering on previous projects. They approached IMI Hydronic Engineering once again for support in finding the optimum hydronic solution to meet the customer’s requirements.

IMI Hydronic Engineering met with TF Service AB to develop an in depth understanding of the existing system and the customers’ objectives for this overall renovation.

Together, they designed and built a system solution to achieve a fully balanced system through the appropriate use of balancing valves, including the STAD valve, and differential pressure controllers.

Optimum room temperature control was achieved by making use of thermostatic radiator valves, such as the TRV 2. In addition to improvements in the heating system, further efficiency gains were realised through better control of hot drinking water and close cooperation with the pump supplier.

Continuous measurements show that these changes not only increased comfort for the tenants but also significantly cut annual energy consumption by 15%.