A Look Inside The HP 21 Black Ink Cartridge
We cracked it open and took a look.
HP 21 Black Ink Cartridge (Retail Price):
Inside the HP 21 c9351a Black Ink Cartridge:
- Color : Black (60% of cartridge is empty space)
- Part Number : c9351wn – HP 21+
- Ink Type : Pigment based ink
- Page Yield : 190 pages*
- Storage temperature : 59 to 95° F
- Estimated Ink Volume : 5ml
- Retail Price : $14.99
- Street Price : $14.49
*that 220 page estimate is from HP and based on 5% coverage (see what 5% coverage looks like) – printer manufacturer estimates are not very realistic in our experience.
+often paired with HP tri-color (color) cartridge HP 22 C9352wn
Want to reset the ink monitor after refill?
Just follow these four (4) steps to reset the ink monitor level for HP 21, 22, 56, 57.
- Turn off the printer and unplug power cable from the rear
- Press and hold “ON” and “Cancel” buttons – plug in printer
- Release both buttons *only* after any led lights stop blinking
- Printer will do full reset, and inkjet printer cartridge level is 100%
Used in these printers:
- HP Deskjet 3910/3920 Printer series
- HP Deskjet 3930/3940 Printer series
- HP Deskjet D1300 Printer series
- HP Deskjet D1360 Printer series
- HP Deskjet D1400 Printer series
- HP Deskjet D1500 Printer series
- HP Deskjet D2300 Printer series
- HP Deskjet D2360 Printer series
- HP Deskjet D2400 Printer series
- HP Deskjet F2100 Printer series
- HP Deskjet F300 Printer series
- HP Deskjet F380 Printer series
- HP Deskjet F4100 Printer series
- HP Deskjet F2200 All-in-One series
- HP Officejet 4300 All-in-One series
- HP PSC 1400 All-in-One series
Cracked open – a look inside the HP 21 c9351a cartridge:
Contact! – Contact!
These solder points, or contacts help make up the print head. Printers that use these types of cartridges do not have an internal print head – rather the print head is located on the cartridges themselves. If print quality declines to the point where the cartridge is no longer usable, simply try another cartridge (it’s like getting a new printer). If your cartridge cannot be recognized, give the contacts a quick clean with a damp cloth, or other device and try again. If the contacts are harmed, the cartridge may not function at all.
If refilling this cartridge, here is a picture of the top, with HP 21 sticker removed. Notice there is only one pre-drilled hole, and that is where the black ink goes. Refill in top hole – where sponge is located, the other part of the cartridge is empty space.
The HP 21 Print Head:
Many refill attempts are foiled by a dirty or clogged print head. When refilling cartridges, they should be refilled right before the ink is depleted, or immediately after they run out of ink. The longer a cartridge sites, the more likely that ink will dry inside the print head and cause clogging. If your print head becomes clogged, use a wet paper towel and gently clean off the print head surface.
The HP 21 tri-color (color) inkjet printer cartridge does not contain very much ink (5ml). If printing more than 100 – 200 pages per quarter, it would be wise to avoid printers that use this cartridge. Hewlett Packard tries to trick their own customers with a deceptively low cartridge price ($14.99) without also mentioning that the cartridge is not completely full. This cartridge contains a measly 5ml of ink, and will run out quickly – there are better options out there. What is sad is that this cartridge could take a bunch more ink, but the electronics doom this cartridge to 5ml of ink performance.
If you are stuck with using this cartridge – look here for the best pricing.