Over the years, as technology changed and new products were introduced, we have made changes to the various control boards we have used in our roof top units.
For many years we used a simple “lock-out relay” board — one for single stage cooling and one for 2 stage cooling. With the addition of diagnostic flash codes to boards, these boards were replaced with ourSimplicity®line of boards.
The Simplicity® 1A board was introduced with our Predator line of units back around 2000. We still used the “lock-out” relay board on the large and small Sunline units.
In 2003, we started to use the Simplicity®1A board in the small Sunline units and continued to use it until August, 2006 when the Simplicity® LITE was introduced. We also started using the Simplicity®1A in the larger Sunline and Magnum units in 2003.
Because we have used the Simplicity® LITE and 1A boards in the Small Sunline units, it is VERY IMPORTANT to look at the serial number of the unit to make sure you get the correct board if ever you have to replace it.
I have attached a “decoder” for the various boards at the end of this posting. Be sure to look it over and note the serial number/dates for each board. By using this, you can be pretty sure you will get the correct board if ever you need it.