Continue preparing the Adiabatic units for winter by completing the instructions in "Supply header blowdown (on page 78)."
Supply header blowdown
Before you begin the process below, be sure to complete the steps in the following sections:
1.Supply header gravity drain (on page 76)
2.Adiabatic unit by unit blowdown (on page 77)
Be sure that all Adiabatic units are isolated from the supply header. If all Adiabatic units are not isolated from the supply header, see "Adiabatic unit by unit blowdown (on page 77)." To be sure the maximum amount of water is removed from the entire supply header(s), complete the following steps:
IMPORTANT: Be sure air pressure is available to complete the next steps.
1.Pressurize the supply header to
2.Open the supply header drain valve to release the air pressure and water.
3.Close the supply header drain valve when the header pressure is zero.
4.Repeat the steps to open and close the drain valve for five cycles, or until no water remains.
At this point, all headers are at atmospheric pressure, all water is removed from the system, and all power is removed at each Adiabatic unit.
5.Remove the garden hose and air adapter assemblies, and then replace the previously removed plugs.
Maintenance 78
