many years ago I worked at a company, the new owner decided to elminate heat in most of the building to save money. he ordered the sprinkler system turned off and drained. plumbers worked for days blowing down the system. it was freezing weather.
a month later the fire marshall paid a visit and ordered the building evacuated and condemed unless the sprnkler system was turned back on
so the heating system was reactivated, and they turned the water to the sprinklers back on.
a major flood occured, many areas had low spots in the lines, so the plumbers spent 2 weeks replacing frozen broke sprinkler lines, and then converting to a dry sprinkler system.
rumors said they could of heated the warehouse all winter for the cost of the plumbers.
the plumbers smiled all the way to the bank.
before another winter the business closed, the building sold to the state for a highway project, and the building was demolished......
Better to install a generator to provide emergency heat, than blow out the lines.
the building can be used in a emergency as a neighborhood shelter