HP2420 Manual Hi, I have a 2420n and am trying to replace the "fuser unit" (the bit under the toner cartridge in case I have named it incorrectly) I have all the parts as part of a kit - complete with rubber gloves - but cannot find instructions anywhere. From first looks I can see that I need to unscrew / dismantle several pieces so would like to know where I can find instructions or a tech manual for the printer. Many Thanks in advance

Hi
You will probably need to replace the toner cartridge.

If you are certain it is not nearing empty, try removing the cartridge, putting in a plastic bag and giving it a little shake. Then clean the area around where the toner comes out both on the cartridge and on the printer.
That might help a little, but generally once it starts fading it means you are coming to the end of the toner/ or possibly fuser unit

You might also try changing your settings to print higher quality. That might allow you to get a few prints out a bit clearer, but will also speed up the demise of your cartridge

On these machines the blurry prints is usually due to bad fuser sleeves, or worn out fuser roller and sleeve on the fuser. You may replace the fuser unit or just order sleeve and roller for your model and replace them on the fuser. Will take about 2 hours of your time. To check if the blurry prints are due to fuser issues, just swipe your hand over the printed page and if you have toner dust on your hand, the fuser is not cooking the toner on the paper. Fuser roller and sleeve are bad and need replacing.

Run a "half test". Put paper in the manual feed tray(tray 1). Print anything. Watch the paper. When it gets about 1/2 way into the printer, open the top cover. Remove the toner. Look down at the paper. Do you see the "usual" line? If yes, replace the toner cartridge. If no the fuser is probably bad.

In cases of print quality issues you should always start with the imaging drum. In this case the toner cartridge. Make sure it is not a re-manufactured or refurbished toner cartridge. A lot of times when someone refurbishes the cartridge they don't replace the imaging drum (the blueish green drum under the shutter). Check for toner stuck or burned on the drum. If there is you need to replace the toner cartridge

If there is no toner stuck or burned on the imaging drum then you more than likely you will need to check or replace the Fuser in the back of the machine. The back door of the machine comes out easily enough and the fuser clips into place. **Be careful it doing to be hot.** Remove the fuser and check the rollers inside for burned toner or damage. If so replace the fuser .

You can purchase a Fuser Kit from HP or find a refurbished fuser from Depot America or OrionMarket.com for a lot less.

Lines are usually caused by the toner cartridge or the fuser. In order to determine the cause you can replace the toner and see if the lines go away. If not then it is in the fuser assembly and you would need to replace the fuser.

Hi:

Since you have already replace the toner cartridge then the most likely culprit is the fuser assy. You can test this by trying to print something and stop it by opening the cover just as the paper is trying to pass under the toner cart. Remove the toner cart carefully and look at the unfused print on the paper. Do you see the faint smudges? If not, then the problem lies with the fuser assy. This is the unit that gets hot and fuses the toner to the paper. If this is the case you will need to have a tech replace it for you.

Good Luck

Andrew

most likely its the fuser. There is burnt toner on the fuser and its damaged

Are you sure it's not the transfer roller that you want to replace?? this is the roller which sits directly under the toner cartridge, the fuser sits more towards the rear of the printer. I'll list instructions for removing both. Hope this helps


To remove the transfer roller -
1. Release the left end of the transfer roller by using needle-nose pliers to pinch two tabs at
the left end of the transfer roller.
2. Use the needle-nose pliers in the same manner to release the other end.
3. Lift the transfer roller out of the printer.
The left end of the transfer roller has a spring attached. At the right end of the roller, the
spring is attached to the printer rather than to the roller. As a result, the spring at the right
end remains in the printer.


To remove the fuser -
1. Remove the back cover and the I/O cover.
2. Remove the fuser-cable cover by releasing one tab on the cover, and then
rotating the back of the cover toward the center of the printer.
3. Remove the duplexer inlet guide by releasing two tabs on the guide, and then
sliding the guide toward the back of the printer.
Reinstallation tip
Make sure that both tabs snap back into place when reinstalling the duplexer inlet guide.
4. Disconnect two cables at the left, inside, of the printer.
5. Disconnect the fuser cable at the right side of the printer.
6. Remove four screws securing the fuser.
7. Tilt the fuser slightly toward the back of the printer, and then slide the fuser out of the
back of the printer.

To remove the back cover -
1. Open the face-up delivery door all the way, and then press the door down to disengage
two door-stops.
2. Remove two screws
3. Close the face-up delivery door, and then tip the printer so that it rests on its front.
4. Open the "legal-size" cover, and then disengage one tab.
5. Lift the bottom of the cover first, and then lift the cover away from the printer.
6. Tip the printer back so that it rests on its feet.
To remove the io cover (looking at the printer from the rear, this is the small cover on the left side) -
1. Rotate the I/O cover to clear tabs at the right side of the cover.
2. Lift the cover off of the printer.

In my experience, the fuser has always been the cause of the lines.