How often does a Heat Interface Unit (HIU) need servicing?

Heat Interface Units (HIUs) have an annual maintenance requirement to ensure safe working and optimum performance. This is of particular importance in hard water areas or where the water supply contains particulate matter. It is essential that the safety relief valve(s) are periodically inspected and manually opened to ensure no blockage has occurred in the valves or discharge pipework. Similarly cleaning of the district heating flow strainer filter mesh and the cold-water inlet filter will help to prevent possible operational faults. Other areas to check are the gas charge in the expansion vessel and the pressure gauge within the heating system. 


The annual service should be recorded in the service record of the HIU. 


Take a look at Baxi's AquaHeat HIU 

For homes fed with heat from a heat network, the Baxi AquaHeat is the answer to your apartment’s heating and hot water requirements. Perfectly suited to supply heat to communal and commercial premises in your development.

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