Nozzle clogs on HP Z series and Epson 7900

[alan a]

One of the big problems with ink jet printers is the clogging of print heads and nozzles.  This has been one of the biggest problems with previous generations of ink jet printers and a source of major annoyance, as many of us can testify.

That hasn't been addressed in previous threads on the 7900 and Z3100/3200 and I was wondering if those who have used the 7900 can comment.  My comments below on the Z series are based on owning one.

The Z series solved the problem of nozzle clogs by having the printer check the nozzles approximately every six hours, and it does so automatically. For that reason, HP recommended that the printer never be turned off, so that the Z3100 can wake itself from "sleeping" every six hours, do the nozzle check, and then go back to sleep. The Z series uses very little ink in this auto process, as compared with the power cleanings on older generations of Epsons that used a lot of ink to keep the nozzles clear of clogs.  This automatic process can maintain the Z series printer and the nozzles even if the printer is not used for weeks at a time, such as when you're on an extended vacation.

However, the Z3100 incorporates a hard drive that is spinning at all times.  (I don't know if the the spinning drive is tied into the function of waking  up the printer every six hours or so, but assume so.) While this system works great, I have always been concerned that hard drive failure could cripple the printer, and had an HP tech/service guy provide me with the part number for the drive if I ever needed to replace it myself without paying $1000 or some other extravagant charge for a service call.   The Z series also doesn't have a user replaceable waste ink tank like the Epsons.  That part also must be replaced by a technician, although I don't know how often, and I haven't experienced any problem in that regard thus far.

From my own experience, the Z series has completely solved the problem of nozzle clogs, but not an issue related to accumulated ink on the heads.  The print heads accumulate ink and must be periodically removed and manually cleaned.  You know when you have to manually clean the print heads when black ink marks appear on the margins of the paper -- the edge of the paper picks up the ink residue from the print heads.  Manually removing and cleaning the heads takes about 30 to 45 minutes.  It is annoying when you are in the middle of a time urgent job and start getting black ink marks on the margin of the paper.  If you print only occasionally you might only have to clean the print heads every six months.  Those who use the Z series in a production environment can comment on how often they must clean the heads, but I assume it might be as often as every month or two based on my own experience.  

How does the 7900 compare to that?  The below questions are not intended to imply any deficiency on the part of the 7900, but only to try to understand how it works based on reading the manual.

* I assume that the print heads on the 7900 are not removable, and thus do not need periodic cleaning as with the Z series.  (I never had that problem with the 4000, and it was several generations ago.)

* From what I can tell by reading the manual, the 7900 does not have an internal hard drive, so failure of that is not an issue.  On the other hand, based on the manual, the 7900 doesn't turn itself on periodically from a sleep mode to check the heads. The 7900 does have user replaceable waste ink tanks as with previous generations of Epsons.

* The manual explains that the 7900 does automatically do a cleaning when the auto checking system says it is needed.  The auto checking system is initiated by printing or turning on the power, among other things.  

Is this a minor cleaning cycle, or the equivalent of the power cleaning on the older Epsons?  The power cleaning used up a lot of ink, and many of us avoided that on older Epsons by printing several nozzle check sheets that then obtain the same result as a power cleaning but used consiberably less ink. If the auto check and cleaning on the 7900 is a power cleaning, then some might choose to leave the auto setting "off" and do nozzle checks rather than auto power cleanings, as with previous generations of Epsons.

* Does that suggest that the 7900 is like other Epsons, and if you don't print for a few weeks, you should still turn it on and run a test print every week or so to keep the print heads clear?

Or, if you are away on a vacation for three weeks and the printer is in a warm room, you will return to nozzle clogs?  

Thanks in advance for any responses or information.

[Ryan Grayley]

* The manual explains that the 7900 does automatically do a cleaning when the auto checking system says it is needed.  The auto checking system is initiated by printing or turning on the power, among other things.  

Is this a minor cleaning cycle, or the equivalent of the power cleaning on the older Epsons?  The power cleaning used up a lot of ink, and many of us avoided that on older Epsons by printing several nozzle check sheets that then obtain the same result as a power cleaning but used consiberably less ink. If the auto check and cleaning on the 7900 is a power cleaning, then some might choose to leave the auto setting "off" and do nozzle checks rather than auto power cleanings, as with previous generations of Epsons.

1. Please see my recent post on this forum about ESP 7900 Automatic Head Cleaning. In summary,  I have already wasted a lot of time and ink because of this 'feature' and I have now turned it off permanently. Epson have yet to respond to my fault report yesterday despite promising to call back within an hour.

2. My ESP 7900 has indeed dropped ink on the leading margins of two A4 test prints on Epson Water Resistant Canvas. It is too soon to say whether this is something I have done wrong but this never happened in six years of using my ESP9600.

Great prints but my confidence in the reliability of this Epson printer is falling rapidly.

This printer is on probation for me and has until mid January. If my confidence in the printer and Epson has not been restored, I will buy an HP Z3200.

Ryan

[alan a]

1. Please see my recent post on this forum about ESP 7900 Automatic Head Cleaning. In summary,  I have already wasted a lot of time and ink because of this 'feature' and I have now turned it off permanently. Epson have yet to respond to my fault report yesterday despite promising to call back within an hour.

Great prints but my confidence in the reliability of this Epson printer is falling rapidly.

This printer is on probation for me and has until mid January. If my confidence in the printer and Epson has not been restored, I will buy an HP Z3200.

Ryan

I found your earlier post. Ryan, based on your experience, it appears that what Epson has done is to automate the power cleaning!  That is not really much of a solution to the clogging of nozzles, since it wastes so much ink.  You had the added problem that the 7900 is telling you to do a power clean and then to do it again, and then again.  And it keeps wasting ink even when the nozzle check shows that there are no clogs.  Based on your experience, it appears that Epson has not really found a way to clean the nozzles without wasting huge amounts of ink.  The solution appears to be the same as with the older generation printers, except that Epson automated the process?   The alternative to that is to ignore the Epson messages about a power clean, and do a nozzle check instead, and if necessary run that two or three times.  You have adopted that approach -- by turning OFF the new Epson feature that was supposed to solve the problem.

Of course, these heads are supposed to be much less vulnerable to clogging as compared with the previous generation of Epsons.  Hopefully those of you who have the printer can let us know if that is, in fact, the case.

It is unfortunate that Epson didn't adopt a solution similar to HP, since HP did largely solve the problem of the clogging of nozzles in the Z seriies.  (But not the problem of having to manually clean the print heads, but I will take that as compared with nozzle clogs or wasting ink -- 11 channels of ink -- with a power cleaning. If Epson has automated the power cleaning, they leave us with no choice but to turn off the feature, so then we are right back to where we started with previous generations of Epsons.)

At least those are my conclusions, based on the reports from Ryan.

[Geoff Wittig]

I found your earlier post. Ryan, based on your experience, it appears that what Epson has done is to automate the power cleaning!  That is not really much of a solution to the clogging of nozzles, since it wastes so much ink.  You had the added problem that the 7900 is telling you to do a power clean and then to do it again, and then again.  And it keeps wasting ink even when the nozzle check shows that there are no clogs.  Based on your experience, it appears that Epson has not really found a way to clean the nozzles without wasting huge amounts of ink.  The solution appears to be the same as with the older generation printers, except that Epson automated the process?   The alternative to that is to ignore the Epson messages about a power clean, and do a nozzle check instead, and if necessary run that two or three times.  You have adopted that approach -- by turning OFF the new Epson feature that was supposed to solve the problem.

Of course, these heads are supposed to be much less vulnerable to clogging as compared with the previous generation of Epsons.  Hopefully those of you who have the printer can let us know if that is, in fact, the case.

It is unfortunate that Epson didn't adopt a solution similar to HP, since HP did largely solve the problem of the clogging of nozzles in the Z seriies.  (But not the problem of having to manually clean the print heads, but I will take that as compared with nozzle clogs or wasting ink -- 11 channels of ink -- with a power cleaning. If Epson has automated the power cleaning, they leave us with no choice but to turn off the feature, so then we are right back to where we started with previous generations of Epsons.)

At least those are my conclusions, based on the reports from Ryan.

I think it's just a matter of different technology. The HP Z printers use heat to fire ink droplets. They have small user-replaceable print heads with about a zillion nozzles each, and a self-mainenance system that continuously tests and maps non-firing nozzles. On the upside, head clogs really are a non-issue, and it's very frugal with ink. On the downside, it's a bit finicky in operation and needs a (completely undocumented!) periodic manual cleaning of the printheads to keep things going. Epsons on the other hand have piezo heads which are fast and require no inky-finger manual cleaning, but they sure do seem prone to clogging, especially in dry climates.
You pays your money and takes your chances.

[alan a]

I think it's just a matter of different technology. The HP Z printers use heat to fire ink droplets. They have small user-replaceable print heads with about a zillion nozzles each, and a self-mainenance system that continuously tests and maps non-firing nozzles. On the upside, head clogs really are a non-issue, and it's very frugal with ink. On the downside, it's a bit finicky in operation and needs a (completely undocumented!) periodic manual cleaning of the printheads to keep things going. Epsons on the other hand have piezo heads which are fast and require no inky-finger manual cleaning, but they sure do seem prone to clogging, especially in dry climates.
You pays your money and takes your chances.

Thanks for the clarification.  But why couldn't the HP Z solution of checking the heads every six hours be applied to Epson's different type of print heads?  I assume that it is those frequent checks of the nozzles and ejecting small amounts of ink that prevents clogging in the Z series.  That is basically what many Epson owners did with the older printers -- printed off a nozzle check every day or so, to prevent any drying or clogging of the ink in the print heads.  HP does it for you in the Z series, which is a great feature if the printer is left idle for several weeks or longer.

It is still not clear what type of cleaning Epson is using with the new automated system that was supposed to solve the problem, but based on Ryan's report it apparently involves a large flush of ink and a power cleaning, which is no solution at all.  At least not an economical one.

Given the Epson is really advertising this new feature and new solution to head clogging, I hoped it really was just that -- a new solution that works.

[Doombrain]

1. Please see my recent post on this forum about ESP 7900 Automatic Head Cleaning. In summary,  I have already wasted a lot of time and ink because of this 'feature' and I have now turned it off permanently. Epson have yet to respond to my fault report yesterday despite promising to call back within an hour.

2. My ESP 7900 has indeed dropped ink on the leading margins of two A4 test prints on Epson Water Resistant Canvas. It is too soon to say whether this is something I have done wrong but this never happened in six years of using my ESP9600.

Great prints but my confidence in the reliability of this Epson printer is falling rapidly.

This printer is on probation for me and has until mid January. If my confidence in the printer and Epson has not been restored, I will buy an HP Z3200.

Ryan

If you've had the printer before November then you've got a pre-launch sample which is different from the mass production units selling now so it's not really the best unit to be reporting conclusion on. Long start up times is normal for a red or blue label printer.

The 7/9900 doesn't run though power cleans unless told to, instead it uses the AID system which can check each nozzle by charging the head and firing ONE ink droplet on to a sensor.
If there's drops on M and K then those two channels will be cleaned, if there's only drops missing on O then only that channel will be cleaned and so on, my point is not the whole head. if the unit is OK this process takes 0.003ml of ink per channel and no media.

[Ernst Dinkla]

The HP Z3100 has a very simple capping station where the heads park when idle. If the printer isn't used for a longer period and does its regular nozzle activation/nozzle check (if kept on power) then some ink accumulates on that capping station and that transfers partly to the head surface. That's what can drop off when the heads are used again after a period like that. At least in my experience. It hardly happens in normal use. Next to or instead of cleaning the heads, a wipe over that capping station lid with the head out of the way (cutter replacement mode) has been my remedy when it has been idle for a longer period.

The story that HP solves nozzle clogs with nozzle replacements is highly exaggerated, it happens as a last stage when other processes do not solve the problem. No heads changed here in 20 months so I presume there are enough nozzles available for a swap if needed. And the printer still frugal on ink.

One or two messages on the Epson 7900/9900 head clogs and cleaning issues isn't telling much. If it become a more frequent topic when more printers are installed then Epson can go back to the drawing board.



Ernst Dinkla

Try: http://groups.yahoo.com/group/Wide_Inkjet_Printers/

[alan a]

The 7/9900 doesn't run though power cleans unless told to, instead it uses the AID system which can check each nozzle by charging the head and firing ONE ink droplet on to a sensor.
If there's drops on M and K then those two channels will be cleaned, if there's only drops missing on O then only that channel will be cleaned and so on, my point is not the whole head. if the unit is OK this process takes 0.003ml of ink per channel and no media.

Thanks very much for the clarification on how the new nozzle checking system operates.  That would be similar to how the HP Z series functions.  

The information you provide is not in the manual or Epson sales literature, however.  What is the source of your information?  Epson?  Can you point us to any Epson literature that explains how the cleaning process functions?  

Do you also know what the difference is between "normal" clean and "power" clean?  We know that power clean uses a large amount of ink.  But the manual doesn't tell us what normal clean does.  It apparently is not a cleaning of only selected colors, because that is a separate option.  So the implication is that normal clean works on all colors simultaneously.

The manual appears to suggest that the automatic system uses "normal" clean, which applies to all colors.  That is similar to the report that Ryan is providing.  It is certainly possible that the first units for sale, that are shipping in the next month, use a significantly different system than that described by Ryan, but it should be noted that I believe that Ryan got his 7900 only in the last month.  It is unlikely, but possible, that Ryan's unit uses a radically different cleaning system than what is included in units that will actually be sold to end users in the next month.  Whether Ryan's unit is defective, and telling him that he needs a power clean when he doesn't, is a different issue.

[Ryan Grayley]

If you've had the printer before November then you've got a pre-launch sample which is different from the mass production units selling now so it's not really the best unit to be reporting conclusion on. Long start up times is normal for a red or blue label printer.

My printer was delivered on November 10th. If it is a pre-launch sample, then under UK consumer law it has been mis-sold to me and this would be of far greater concern than the non-functional Automatic Head Cleaning.

Ryan

[Doombrain]

That's why I said before November, Ryan.

Edit: It wasn't until after posting I checked your site. You must have a full production unit.

[Ernst Dinkla]

The HP Z3100 has a very simple capping station where the heads park when idle. If the printer isn't used for a longer period and does its regular nozzle activation/nozzle check (if kept on power) then some ink accumulates on that capping station and that transfers partly to the head surface. That's what can drop off when the heads are used again after a period like that. At least in my experience. It hardly happens in normal use. Next to or instead of cleaning the heads, a wipe over that capping station lid with the head out of the way (edit: head replacement mode) has been my remedy when it has been idle for a longer period.

The story that HP solves nozzle clogs with nozzle replacements is highly exaggerated, it happens as a last stage when other processes do not solve the problem. No heads changed here in 20 months so I presume there are enough nozzles available for a swap if needed. And the printer still frugal on ink.

One or two messages on the Epson 7900/9900 head clogs and cleaning issues isn't telling much. If it become a more frequent topic when more printers are installed then Epson can go back to the drawing board.



Ernst Dinkla

Try: http://groups.yahoo.com/group/Wide_Inkjet_Printers/

[Wayne Fox]

Thanks very much for the clarification on how the new nozzle checking system operates.  That would be similar to how the HP Z series functions.  

The information you provide is not in the manual or Epson sales literature, however.  What is the source of your information?  Epson?  Can you point us to any Epson literature that explains how the cleaning process functions?  

Do you also know what the difference is between "normal" clean and "power" clean?  We know that power clean uses a large amount of ink.  But the manual doesn't tell us what normal clean does.  It apparently is not a cleaning of only selected colors, because that is a separate option.  So the implication is that normal clean works on all colors simultaneously.

The manual appears to suggest that the automatic system uses "normal" clean, which applies to all colors.  That is similar to the report that Ryan is providing.  It is certainly possible that the first units for sale, that are shipping in the next month, use a significantly different system than that described by Ryan, but it should be noted that I believe that Ryan got his 7900 only in the last month.  It is unlikely, but possible, that Ryan's unit uses a radically different cleaning system than what is included in units that will actually be sold to end users in the next month.  Whether Ryan's unit is defective, and telling him that he needs a power clean when he doesn't, is a different issue.

A basic description of the process is here.  http://www.epson.com/cgi-bin/Store/jsp/Pro...etection&BV

There is some assumption that a single droplet is fired through each nozzle, which would be a few picoliters per nozzle per channel . I haven't actually seen that documented, in the link Epson states the amount is miniscule.  

The 7900 uses the same basic head technology as the 11880, which I have had running for over a year now, with one single color partially clogged after the printer sat idle for about 2 months. I have the auto nozzle clog test set to run occasionally .. no need to run it between every job, clogging really isn't much of an issue.  I turn the printer off if I'm not going to use it the next day.  I assume it does a nozzle check when I turn it on - that would make sense - but I've never really tried to check ... not really too worried about it.  I live in Utah, which is a pretty dry climate, and I don't have a humidifier in the house, so in the winter humidity is really low. If I haven't used the printer for a week or two, I'll normally just run a manual nozzle check pattern myself.  It is been the lowest maintenance printer I have ever owned ... it just runs without issue.

As far as cleaning, there are basically 3 different methods.  You can set the printer up to clean any of the channels, which implements a "normal" cleaning cycle of that channel. I believe this is what the printer does if the auto system detects a clog.   You can also have the printer clean all channels, which is a "normal" cleaning cycle.  A power clean which is a much more aggressive cleaning is never automatically started by the printer. The printer will recommend trying a power clean if 3 normal cleans don't clear the clog.  I don't know what the actual difference is between the two, but obviously it is much more aggressive cleaning.  I have only used the single channel method one time.

Lots of talk about clogging for a printer that from my perspective is pretty much clog free.

[alan a]

It is been the lowest maintenance printer I have ever owned ... it just runs without issue.

As far as cleaning, there are basically 3 different methods.  You can set the printer up to clean any of the channels, which implements a "normal" cleaning cycle of that channel. I believe this is what the printer does if the auto system detects a clog.   You can also have the printer clean all channels, which is a "normal" cleaning cycle.  A power clean which is a much more aggressive cleaning is never automatically started by the printer. The printer will recommend trying a power clean if 3 normal cleans don't clear the clog.  I don't know what the actual difference is between the two, but obviously it is much more aggressive cleaning.  I have only used the single channel method one time.

Lots of talk about clogging for a printer that from my perspective is pretty much clog free.

Thanks very much for sharing your experience.  It appears, in Ryan's case, that the new printer incorrectly reported a clog and recommended a power clean.  Ryan then chose that option, which uses up a lot of ink.  The printer then reported that the clog continued, and recommend a second power clean.  Ryan did that, assuming that he should do what the printer told him to do.  At that point Ryan was running out of ink.  Ryan can confirm, but that is my understanding based on his two posts in this thread and the other thread.

Several have now reported that you only have to do a power clean if you voluntarily accept that recommendation from the printer, and that is consistent with Ryan's report.  When I owned a 4000 (a very old printer by today's standards) it would also recommend a power clean on occasion.  I learned to ignore the printer.  Instead, I ran one to three nozzle checks.  By forcing the printer to do nozzle checks, and just keep printing, it had the same effect of cleaning the nozzles -- without wasting the ink from the power cleans.

However, the 4000 only recommended a power clean when it was really necessary -- and even then I could ignore the recommendation.  In Ryan's case the 7900 was recommending a power clean immediately after it already did a power clean, and when there were no clogs at all.  As confirmed by Ryan when he did a manual nozzle check.  So the question, in his case, is why the 7900 reported, in error, that the nozzles were so clogged that a power clean is necessary.  It is the erroneous report on the part of the printer that is the basis for Ryan's complaint, and it would suggest that in the case of his printer, the AID system is incorrectly reporting a clog where there isn't one.

Anyway, even with the 4000, I would ignore that instruction from the printer, and it may be that we must do that with the 7900.  

Wayne, your explanation is greatly appreciated.  It is good to know that the new system that Epson included on the 11880 and the 7900 works so well.  Thanks very much for your great explanation.

[Mussi_Spectraflow]

The documentation I have says that if a clog is detected during the auto check, then printer executes cleaning only to the nozzle line. It's not entirely clear to me if each of the 10 lines can be cleaned separately or in groups of two. Regardless the auto cleaning seems to be specific to the clogged color rather than to all colors, and surely not on the level of a power clean.

[stevegoldenberg]

The documentation I have says that if a clog is detected during the auto check, then printer executes cleaning only to the nozzle line. It's not entirely clear to me if each of the 10 lines can be cleaned separately or in groups of two. Regardless the auto cleaning seems to be specific to the clogged color rather than to all colors, and surely not on the level of a power clean.

What's the early verdict from owners of this printer? How much clogging is occurring with real-word use?

[jbm007]

[quote name='goldmember' date='Dec 29 2008, 12:39 PM' post='247734']
What's the early verdict from owners of this printer? How much clogging is occurring with real-word use?
[/quote


None.

[Ryan Grayley]

What's the early verdict from owners of this printer? How much clogging is occurring with real-word use?

For clogging, my Epson 7900 is worse than my 6 year old Epson 9600. It also wastes a lot more ink due to excessive 'cleaning' even with the Auto Nozzle Check disabled. At the beginning of December, I reported this nonsense twice to Epson UK Business Graphcis and I am still waiting for a response to both calls. I don't think I have ever known worse customer service and I will be making a formal complaint to Epson when I have a little more time. With hindsight, I wish I had bought a HP Z3200.

Nice prints though.

Ryan

[stevegoldenberg]

For clogging, my Epson 7900 is worse than my 6 year old Epson 9600. It also wastes a lot more ink due to excessive 'cleaning' even with the Auto Nozzle Check disabled. At the beginning of December, I reported this nonsense twice to Epson UK Business Graphcis and I am still waiting for a response to both calls. I don't think I have ever known worse customer service and I will be making a formal complaint to Epson when I have a little more time. With hindsight, I wish I had bought a HP Z3200.

Nice prints though.

Ryan

Wow, that's pretty terrible.  What are others' experiences with the 7900?

[jbm007]

Wow, that's pretty terrible.  What are others' experiences with the 7900?

I think you have to evaluate your environment. We both have the same machines. I print every 2-3 days. I do a nozzle check every time I print.

My humidity level is about 50 - 60 %

He either has a lemon for a printer or something is horrible wrong with his environment.

These new machines are a 10 times improvement in workmanship. These are very big, extremely well built and very, very, heavy machines.

They really make the older 7800 series printer look like toys.

So take that with a grain of salt.  You can expect many opinions regarding this; but in the long run none will reflect your printing workflow, and your printing environment.

And, as for his hindsight? I did carefully look at both printers and in my hindsight.........  I made the correct move.

Epson needs to step to the plate and fix his situation. I am sure the holidays are having an effect on how much help he is getting.

[Farmer]

For clogging, my Epson 7900 is worse than my 6 year old Epson 9600. It also wastes a lot more ink due to excessive 'cleaning' even with the Auto Nozzle Check disabled. At the beginning of December, I reported this nonsense twice to Epson UK Business Graphcis and I am still waiting for a response to both calls. I don't think I have ever known worse customer service and I will be making a formal complaint to Epson when I have a little more time. With hindsight, I wish I had bought a HP Z3200.

Nice prints though.

Ryan

With the auto check turned off, why would it be wasting any ink - when is it running cleaning cycles if you're not telling it to?