Vaillant 509121 packing ring (Pack)

These Vaillant packing rings, supplied in a pack of 10, are designed for use in the heat exchanger of ecoTEC VU (condensing), ecoTEC VUW (condensing), ecoMAX VU (condensing) and ecoTEC VUI (condensing) boilers. O-rings, gaskets and washers are used in many different areas of the boiler to join parts to pipework. Among others sections, heat exchangers and gas valves require these parts to prevent gas and water leaks.