Delta T Pro Version 4.2.X firmware is for use with older style controls that use jumper pins for "ON-OFF-AUTO" settings -- DO NOT USE THIS FIRMWARE ON CONTROLLERS THAT HAVE AN ON-OFF-AUTO SWITCH. Loading incompatible firmware may cause a controller lockout and will void any warranty claims. The firmware software file has a .BIN extension. This file has been inserted into a folder then compressed into a .ZIP file for download below. Make sure to select the version applicable to the controller. The Delta T Pro Ethernet firmware cannot be updated over the internet -- updating the firmware requires the use of special cables (contact your installer for details).

Delta T Pro Version 4.5.3 firmware is for use ONLY with controls that have an "ON-OFF-AUTO" switch -- DO NOT USE THIS FIRMWARE ON CONTROLLERS THAT USE JUMPER PINS FOR ON-OFF-AUTO SETTINGS. Loading incompatible firmware may cause a controller lockout and will void any warranty claims. The firmware software file has a .BIN extension. This file has been inserted into a folder then compressed into a .ZIP file for download below. Make sure to select the version applicable to the controller.The Delta T Pro Ethernet firmware cannot be updated over the internet -- updating the firmware requires the use of special cables (contact your installer for details).