I can guess what the PO did. He connected the Schrader valve to the drain port on the bottom of the faucet, which was totally unnecessary. I set a flat concrete cap block in the bottom of the hole for the faucet to sit on, install it with at least an 18" section of pipe supplying a 90° elbow on the bottom of it, for stability, Install a 90° 1/8" brass street ell in the drain hole and pack rock around the base of mine, to allow the drain hole to drain. Since the PO has closed the drain hole off with the pipe and Schrader valve, you really don't have any choice but to do as he suggest, and blow air thru it, as it will not drain on its own now.
NEVER leave a hose attached, this traps water in them and they freeze anyhow. If you must leave a hose attached, install it with a vacuum breaker on the spout.
The PO may had made this UN-orthodox modification to the hydrant because its possible your water table is close to the surface, and may prevent the faucet from draining properly. In the north, the bottom of the hydrant must be below the frost line, which in some places can be six to eight feet. The total height of the hydrant could be as much as ten feet. Here in the south, a four foot total height (two foot under and two foot out of the ground) is way more than sufficient to keep it from freezing and allow it to drain properly.
Another possibility is that the PO did not use one tall enough to reach the frost line, and so it needs to be blown out to keep the bottom from freezing.
Charles
