Checking AC of Heat Pump in Cold weather

Can someone please tell me if it’s okay to check the cooling mode of a Heat Pump system when it is way below 60 degrees outside (i.e. 45 degrees). I know the “rule of thumb” for a coiled AC unit is to not check it due to possible damage to the compressor, but does this same rule apply with the cooling mode of a heat pump? Thanks in advance for the reply(s).
Mike Gotcher

When the heat pump goes in defrost, that is the AC mode.

You should attend the ORICA conference this month in OKC I will be covering your question in detail