?
Favorite Answer
The valve on a hydrant is like garden hose valves, ie the valve in on the end of a long rod that reaches down into the ground or into the warm house, and the space outside of the valve drains when not in use.
https://www.youtube.com/watch?v=Q32FWiWf7rk
Mark big sky boat man
Pressure.
Some Body
The pipes are buried below the frost line (underground temperature is warmer in the winter and cooler in the summer). The tube connecting the hydrant to the water pipes stays empty except during use.