nope in a normal Cold area plumbing system right by crawlspace door theres a knurled fitting on cold shut off valve you tuir off valve oplen this fitting water runs out of house pipes to floor or bucket now nothing can freeze f
What?
Its an air bleed. Looks like this:
(broken image removed)
When you close the shutoff to drain the pipes, for the water to run out air has to enter the pipe to replace that water. If there is a long run from the shutoff to the nearest tap sometimes the air cant get back to the shutoff up the pipe, so having an air bleed like this to open makes it easy.
Process is like this:
1 Close shutoff
2 Open all the taps
3 Open the air bleed
4 wait for water to stop running
5 close air bleed