NEST Blowing Cold Air on Heat Mode

[ryanjames13044]

• Good evening,

When I initially installed my Nest, everything worked flawlessly. Randomly, after setting some schedules, my NEST started blowing cold air on heat. Now, after resetting and reconfiguring, my NEST is still blowing cold air on heat. As I type this, I’m testing to see if the modes are switched (heat on cool / cool on heat). But regardless, when I have HEAT mode on, cold air is blowing through the vents. I have switched my W1 wire to the OB wire to see if that fixed the issue (it has not). As of typing this, I’m seeing if the modes are reversed and I have put the COOL mode on (set to 68°) to see if that helps heat the home. Please, let me know what I can do to fix this. To my knowledge, I have an electric heating system (I have a gas stove) and a heat pump as well (I have a unit outside with a fan - I believe for AC). This is my first home and I’m not too privy as to to what is what, so I’d appreciate some fellow gentlemen guiding me into adulthood. Thank you. 

Attached, I will provide a screenshot of my NEST settings as well as my wire configuring at the time of this post. Again, my W1 wire is placed in the *OB to see if that fixed the issue, but again, I’ve tried switching the mode to COOL to see if that heats the house. And right now, set on COOL 68°, I have ZERO cold air blowing and the house seems to be heating. Thank you fellow brothers. 

[CoolingWizard]

@ryanjames13044 ,

when you have a heat pump system, the outdoor unit will always run whether it’s cooling or heating. What makes a heat pump work is there is a valve outside called the reversing valve that changes the direction of the flow of the refrigerant, which changed it from a heater to an air conditioner or from an air conditioner to a heater. The easiest way to see if your system is working correctly is when you were in heat mode, the outdoor unit should be running. There are two pipes coming to the indoor unit. A large one and a small one. In heating mode the large one will be hot and the small one will be cold. If they are both cold. This indicates your heat pump is low on refrigerant. If the little one is hot and the big one is cold, the system is running in air-conditioning mode.

on atypical thermostat the wire attached to *OB is what controls that reversing valve. 
there are two types of heat pumps sold in North America. There’s the type O and the type B. Type O heat pumps are heaters by default and when you switch the valve, they become air conditioners. Type B models are air conditioners, and when you switch the valve, they become heaters. 
right now people reading this are going why in the heck do they make two different types. The concept is if the reversing valve coil fails, you want it to be in the default mode. Down south where it’s hot more than it is cold, they use type B. in the northern states where it’s more heat and less cooling they tend to use type O.  in all reality about 94% of all systems sold in America are type O. 

AC Cooling Wizard