Is it safe to run the cooling system when it is cold outside?
No — to prevent possible compressor damage, do not operate the cooling system when the outdoor temperature is below 50°F (10°C). Additionally, heat and cool temperature settings in Auto mode must be kept at least 3 degrees apart, and this separation cannot be changed. (Page 3, 14)
From the official Honeywell Focuspro Th6110d manual, page 3
Have a follow-up question?
Answers from the official manual.
Common questions