We had the Autoterm heater installed (beneath the bed) in our 18'7" Feathertop pre delivery in 2022 and it proved to be a wonderful no-fuss, no smell/no gas & quiet heater. I did upgrade to the comfort controller later on & that has various operating modes. We set to thermostat 14deg on frosty nights which then auto starts heating at 1deg below = 13deg, running up to 2deg above = 16deg & cycles as needed. The temp will be as taken from where the controler is placed. The solenoid fuel pump atrached externally to the chassis cross bar beneath the bedhead emits only a very quiet 'tick'; it must be correctly installed within the standard rubber strap damper mounting, and below the diesel tank outlet level to prime readily without air locks.