Security in all measurements on refrigeration systems and heat pumps testo 557 is the ideal partner for all technicians who wish to carry out commissioning, service and maintenance on refrigeration systems and heat pumps quickly and efficiently, and also require documentation of the measurement results. The testo 557 is a digital manifold for commissioning, maintenance and service work on refrigeration systems and heat pumps. It replaces mechanical manifolds, thermometers and pressure/temperature tables. The 4-way valve block allows fast and efficient work, and the integrated vacuum measurement supports the evacuation of a system. - up to 2 NTC probes can be connected - High-quality sensors measure high and low pressure - Calculation of superheating/subcooling in real time - Temperature-compensated tightness testing - Heat pump mode - 40 refrigerants stored