The E-TECH series units are wall mounted and available in five sizes from 4.2 to 36kw. They use modulating control and have durable incoloy heating elements. They have a built in expansion vessel, pump, and automatic air vent. They also offer a domestic hot water generation option as well as a kit to include a second heating circuit. The brand is made in Belgium and is available worldwide but their website does not have a stated warranty policy. acv.com