07-13-2009 06:42 AM
I have a problem with our HP1050C plotter, we are getting an error of "replace 21" for BLACK printhead only.
We have chanegd the printhead twice (printhead from different customers)and the same result, after a few plots it shows replace 21.I cleaned the printhead
and the area where the printhead is inserted still same result.
Any suggestions or help is highly appreciated.
10-26-2009 02:06 PM
You have air in your ink tubes. Take off the sides and the top cover. When standing behind the machine look a the tubes, at the top right where they bend into the top of the unit you can see the tubes. Look a the black tube and look for air bubbles. I have had this issue before. Why does it print cyan, because black on that plotter mixes with cyan when printing black. Also, why does it work for a week then stop, because the printheads come primed with ink. You will get several print out before it stops working again. Very important to replace all parts that could be causing the air to get into the tubes and eventually air gets into the printhead also. You must replace the black ink cartridge, the Ink tube assembly and the black printhead. All must be NEW, do not reuse the black printhead you just put in because it could have gotten air inside it. Furthermore, never never never use refilled in cartridges or try to refill yourself. You will get air in the system. Do not shake cartridges to get the last dropout. Replace as soon as the machine says to. The tech should be able to remore the tubes and inspect for air, but I think this is your problem. This is a great unit the will last. If you already have a new carriage and trailing cable, then replacing the tubes should get you several more years. Just my opinion! If this is an 1050 "A" model, then you might want to upgrade to the new HPT620 that comes out in two weeks. 1050 "A" model main boards are not available, however all parts for the 1050 "B' model are still available kurt <text removed for privacy> You will know by the last letter of our model number C6074A or C6074B
As for the 21 error code, I'll look into it. I've seen that before.
10-28-2009 09:07 AM
Replace 21 printhead message means that the printhead has issues, but will still work. If to many nozzles get blocked then you will get this message. The machine will try to correct the problem and take longer to print. Did you replace the printhead cleaner at the same time? The cleaner wipes the nozzles on the printhead. If the printhead cleaner is dirty with ink then that will get on the nozzles. Also go to printhead information on the menu and see how old the printhead really is. Is it expired? Out of warranty? Visually look at the bottom of the printhead for ink build up. there could be ink rubbing on the nozzles from somewhere else on the machine. also, clean the contact in the carriage. I use a alcohol based cleaner ( rubbing alcohol ) and a swab. printheads can be cleaned with water on a lint free cloth.
08-23-2012 03:36 PM
We we getting various errors; Replace 21, Failed 14, 16 or 17, Faulty 14, 16 or 17. All indicating an error with the black printhead. The fix for us was to replace ALL of the printhead cleaners as well as the black printhead.