I purchased a Nest Thermostat E and found that I don't have C-wire. With the research, including adding venstar to HVAC and Youtube video by Venstar, I tried to add c-wire to my Nest Thermostat E with the Venstar Add-a-wire (ACC0410). However, I can't find exact match with my HVAC control board system. So, I hope that someone experienced with these can help me what to do.
As you see below, it is different from Venstar Youtube video setting. The video doesn't have lines from compressor but mine does. Could you please help me how to connect my Venstar ACC0410 to my control board and what to do with Nest Thermostat E setting?
First, here is my current HVAC control board setting as below.
And, here is my current setting with my Nest without C-wire:
The final implementation is summarized below.