Grundfos Stainless Steel Hot Water Service Pump Model UPS15-50N The Grundfos UPS 15-50N (130) Domestic Hot Water Service Circulator pump with standard 130mm port to port fittings. Suitable for use in the following applications: Circulation of hot or cold water in Domestic hot water recirculation Heating systems Domestic hot water systems Cooling and air-conditioning systems Features and benefits: Maintenance-free Low-noise Low-energy Corrosion-resistant stainless steel,brass pump housing