1-800-397-1392
Today's Hours 8am - 9pm est
Today's Hours 8am- 11pm est
Thank you for your question. This unit is rated to have efficient heating operation with outdoor temperatures as low as 5 degrees Fahrenheit. For climate zones that frequently drop below this temperature, we would recommend a back up heat source. While set to heating, the system will automatically defrost. For more assistance, please give us a call.