I am trying to connect a Nest E thermorstat on my HVAC unit that runs heat and AC. i have yellow-y1, G-green,White-w, red- R. When y1 is connected i get the error No power to R, i see the C wire on the cable, i connected the blue to C and make sure is connected to C on the furnace and AC but i get no power. I have to disconnect C and Y1 for heat to turn on but no AC. temperature in Connecticut now is 60F its not to cold to get those errors. Should i just buy a 24 AC wall transformer and connect it to the R and C cables to the thermostat? Nest tech support tells me C wire is not grounded, but i see it grounded on the board.
You will need a wire going from the C on the thermostat to the C on the furnace, 5 wires total. R to R, W to W, Y to Y, G to G and C to C. At the furnace there will also be a second wire on the Y and C and they will go to your condensing unit. I can not tell from your pictures but it looks like the blue wire on the furnace C is probably going to the condensing unit.