Printing with black ink only

[Klmills]

I am considering purchase of hp envy 7640. I believe it comes with a black cartridge and a tri-color cartridge. When the color ink runs out will I be able to remove that cartridge and print with only the black ink cartridge installed or will I have to purchase another color ink cartridge?
Thank you.

[Bob_Headrick]

The Envy 7640 printer does allow printing in single cartridge mode.  From page 78 of the user manual here:

Use single-cartridge mode

Use the single-cartridge mode to operate the HP ENVY 7640 series with only one ink cartridge. The single-cartridge mode is initiated when an ink cartridge is removed from the ink cartridge carriage. During single-cartridge mode, the printer can copy documents, copy photos, and print jobs from the computer.

---

The following is information I wrote to explain why some printers cannot print with some colors out, it may be of interest.

HP and other printer manufacturers have different printer technologies for different needs.  For inkjet printers:

• Some have printheads built into the ink cartridges.  These printers can typically print with one or more of the colors completely empty, or even with color or black (but not both) cartridges removed. The Envy 7640 is an example.

• Other printers have separate ink supplies and replaceable printheads.  An example would be the Officejet Pro 8600.  The printhead in these printers can be replaced if they are damaged by running the printhead with colors out.  Some of these printers will allow printing with a color out, other will not.  If the printer is run without ink in one or more colors the printer may be damaged, but the user may be able to recover without having to send the printer for service. 

• Other printers have permanent printheads.  To run these without some ink in all the colors would risk causing damage to the printhead due to clogs, air ingested in the printhead or burned out printhead firing resistors. The Officejet 6700 is an example of this type of printer. For printers with fixed printheads this could require service to get the printer to print properly again when the ink is finally replaced. 

The document here describes how ink is used.  While the document is written for HP Inkjet printers the same principles apply to inkjet printers from other manufacturers.