Heat pump blowing cold in heat mode could mean defrost trouble, low refrigerant, or a stuck reversing valve

https://remingtonhihm412.wpsuo.com/how-to-lower-cooling-bills-without-replacing-your-system

Heat pump blowing cold in heat mode could mean defrost trouble, low refrigerant, or a stuck reversing valve. Don’t wait—quick diagnostics in Alpharetta can spare you higher bills and longer run times.