There is no Column Manager maintenance procedure alone, it is included with the Sample Manager. Like maintenance on most column heaters, it is pretty simple. It is a case of fix when broken and inspect operation annually. In the case of the CM, there are two valves, but they are basically the same as the SM injector valve and so rated to high pressure and to 100 K cycles, thus it will take a while before you get beyond the valve lifetime, as the number of column switching events are lower than injections
Here is the link in nay case.
The Col Mgr is part of the version D of the Opertor's Guide and the online help can both be downloaded from the community overview page.
Liz is right column heater or manager is part of sample manager PM, you just notify your vendor that latest Column Manager Firmware updates as well Leak Sensor Assembly Firmware must install at PM, i think at PM they only check leak & temp. sensor or any tubings otherwise it is maintenance free. You can get Column Manager Online Help by this file.