Troubleshooting Only One Fan Speed After Replacing A Dometic Rooftop Unit With An Advent Air Unit

Updated 09/26/2023 | Published 09/25/2023

Question:

Hi I ordered 115014127 and recived a 15K BTU Advent . It replaced a Brisk II B59516.711JG ducted unit . The Duotherm has the control box/ digital 3313192 thermostat set up which just plugs right in the Advent. After the install the unit cools well, the only thing is I now only have Hi fan speed . I assume the Advent is dual speed. Any thing you can sugest I check ? I appresheate your help.

asked by: Mike K

Expert Reply:

It's a pretty common occurrence for there to be communication issues between an old thermostat/controller and a new rooftop AC unit so I recommend checking the owner's manual for your Dometic thermostat or calling Dometic to see if there's any way to reboot the thermostat and if any dip switches need to be changed to properly communicate with the new Advent Air # ACDOM150B.

The other solution would be to replace the air distribution box, controller, and thermostat with part # ACRG15. This would give you all Advent Air equipment and prevent any further communication errors between the rooftop unit and the controls.

expert reply by: Kevin C