German Vaillant has launched a project which has stirred controversy among installers: Online platform heizungonline.vaillant.de can be used by manufacturers to directly address those end customers who wish to shop online – and send them a “price indication” for a complete heating system.German Vaillant has launched a project which has stirred controversy among installers: Online platform heizungonline.vaillant.de can be used by manufacturers to directly address those end customers who wish to shop online – and send them a “price indication” for a complete heating system.