Control device setting order condition for ordering cartridge to be mounted in recording device provided with tank

A non-transitory computer readable storage medium storing a set of program instructions installed on and executed by a computer, the set of program instructions comprising:

• acquiring an index value from a recording device, the recording device including:
• a case in which a cartridge accommodating a printing agent is mountable;
• a tank configured to accommodate the printing agent supplied from the cartridge;
• and
• a recording portion configured to record an image on a sheet with the printing agent supplied from the tank, the index value being representative of one of a first residual quantity, a second residual quantity, and a third residual quantity, the first residual quantity being a residual quantity of the printing agent remaining in a first cartridge, the second residual quantity being a residual quantity of the printing agent remaining in the tank, the third residual quantity being a residual quantity of the printing agent remaining in the first cartridge and the tank, the first cartridge being currently mounted in the case;
• storing the index value in a memory;
• determining whether an order condition is satisfied based on the index value stored in the memory;
• and
• transmitting an order command to a relevant device after the order condition is satisfied, the order command instructing to order a second cartridge for replacement with the first cartridge.

A method executed by a computer for placing an order for a cartridge to be mounted in a recording device including:

• a case in which the cartridge accommodating a printing agent is mountable;
• a tank configured to accommodate the printing agent supplied from the cartridge;
• and a recording portion configured to record an image on a sheet with the printing agent supplied from the tank, the method comprising:
• acquiring an index value from the recording device, the index value being representative of one of a first residual quantity, a second residual quantity, and a third residual quantity, the first residual quantity being a residual quantity of the printing agent remaining in a first cartridge, the second residual quantity being a residual quantity of the printing agent remaining in the tank, the third residual quantity being a residual quantity of the printing agent remaining in the first cartridge and the tank, the first cartridge being currently mounted in the case;
• storing the index value in a memory;
• determining whether an order condition is satisfied based on the index value stored in the memory;
• and
• transmitting an order command to a relevant device after the order condition is satisfied, the order command instructing to order a second cartridge for replacement with the first cartridge.