These self-acting controllers are designed to be integrated directly to heat exchanger. They are developed to control direct heating and instantaneous heating of domestic hot water by means of heat exchanger. The family of products offers full flexibility of different requirements regarding control performance. Innovative design enables simple, fast and reliable connection to heat exchanger and most importantly production of compact and user friendly stations for heating and preparation of domestic hot water. The capacity of controllers fully covers the needs of domestic hot water preparation and heating for flats, one family houses or dwellings. Controllers can be mounted to district heating network, different heating systems or centrally located boiler system in a dwelling house (see “Main data” for specifications for the network).