Vaillant VR71 Wiring Center 20184847 – Direct Heating Supplies
VR 70 / VR 71 - Vaillant - Control Unit for Heating and Cooling
Nicholson Heating on Twitter: "Vaillant EcoTEC plus 637 system boiler with a low loss header and 4 circulating pumps doing 3 x heating zones and one hot water zone with a secondary