So here's the short. Bought a house last year, heat worked perfect for the winter and ac worked perfect for the summer. Now that it's fall again the heat didn't want to work at first but cooling did. Now it's flipped and heat works but no cold air just the fan running. I've tried troubleshooting switching the o/b settings, reset system, reset nest and nothing seems to help. I have the previous wiring from old unit and have double checked current wiring for nest. I don't know how to cool my house at this point.
Sounds like the system has a problem not the Nest.
There is a reversing valve in the outside unit that changes the flow of the refrigerant aka Freon when you change between heat and ac. Possibly the valve is not functioning properly. Might need to get a hvac technician out to check what is going on.
You can test the valve by first disconnect the power to the outdoor unit at the disconnect box. Then removing the wires from Nest and jumper the Red (power) to OB to force the reversing valve to change position. Have someone apply the jumper as you go outside and listen if the valve is making a sound when it energizes. Sometimes just the coil on the valve goes bad and you can replace that. If the internal part is bad you need to recover the refrigerant and cut it out and braze a new one in, then recharge the system.
I will give this a shot tonight when I get home and let you know how it goes just in case I have an HVAC tech coming out Wednesday.
Update it did not charge/make a sound. HVAC tech here we come luckily it's got the manufacturer warranty.
Thanks for the help, @Houptee and @Anonymous.
@VIGALENTDEMON, I appreciate the update and for keeping us in the loop on what you've done to have your concern rectified.
I wanted to ensure that everything was covered here. Please let us know if you have any other questions or concerns.
Just one quick final check in here since activity has slowed down. We'll be locking the thread in the next 24 hours, but if you still need help, I would be happy to keep it open. If there's more we can do, just let me know.
I appreciate the help, Mark and Houptee.