The present invention relates to a method and a heat exchanger arrangement (3, 5) for a dairy processing system, to provide process water to a piston pump or a homogenizer comprised in the dairy processing system. The arrangement comprises an injection port (12, 13, 14) arranged to inject condensate into in at least one of the inlet conduit (1), the by-pass conduit (11), and the third conduit (10), in order to reduce the amount of water and/or energy required to heat the water, and the method comprises the step of injection condensate into the flow of water.
