When not printing, should I leave the printer on (sleep mode) or off to conserve ink and avoid clogs?

See also the FAQ on Ink Used for Cleaning

Update 5/2/09:
The latest recommendations from Canon support techs and impressions from knowledgeable individuals:

  • 10/1/08: The latest consensus according to the tech I spoke to is to keep it plugged in, but powered off. Then, once a week turn it on and let it do its thing and then turn it off again. If left on, every 72 hours it will do a deep cleaning that uses a lot of ink. Every time you turn it on it will do a head check and if anything is starting to clog it will do a light cleaning. Thus, by turning it on once a week you can help avoid serious clogging issues, but also avoid big time ink usage from automatic, but probably not needed, major cleanings.
  • 9/2/08: According to Scott Martin, "Even with the latest firmware updates these printers use a whole bunch of ink when left in sleep mode. A Canon tech told me that in a temperature/humidity controlled environment it should be fine to turn it off when not used in more than 48 hours. So far that's worked great for me and the printers are using quite significantly less ink which is really helpful."

Previous recommendations before update:

  • The official Canon recommendation is to leave the printer on continuously according to Michael Reichmann at the Luminous Landscape. Of course, it will go into sleep mode in 5-240 minutes depending on the setting entered from the printer LCD. It is said that the printer will awaken from sleep mode about once a day and run a small cleaning cycle, which will keep the printhead free from clogs.
    • According to a poster on the Wiki, "the printer will go through a 5 minute cleaning cycle if turned off for 2 to 3 days. Not sure yet on that exact number or days or hours that triggers the longer cleaning cycle. If used every day, then the cleaning cycle is 1 minute long."
    • Another poster reports, "The support tech who came out to fix my roll feed unit recommended leaving the printer's power on at all times- -and he is not a Canon employee. He said the nozzles can clog very easily, and it's just not worth the tiny ink savings you would get by turning it off."
    • Kier Darby states "I'd be inclined to leave the printer on standby unless you know that you won't be printing for a week or more, in which case the longer cleaning cycle will probably use less ink than the short daily cycle."
    • John Hollenberg changed to turning the printer off, but it seemed to be using up a lot more ink when it was turned on each time. He went back to leaving the printer in standby mode; ink usage appears to be less.
  • There are several reports from individuals that knowledgeable techs at Canon support have recommended leaving the printer OFF rather than on (=sleep mode). Apparently, the daily cleaning cycles can add up to a significant amount of ink over time, such that those who print infrequently may use less ink by keeping the printer off.
    • TomH reports: "I just spoke with a Canon tech support rep this morning who told me to absolutely turn the printer off. He stated the printer may automatically initiate a cleaning cycle every few hours and not just one time per day. He further stated the iPF5000 adjacent to his desk has been used to print only a couple of sheets of paper over the last two months. He has kept the machine on 24 hours a day for that period of time. Two of the black ink tanks have been drained in that period of time just by use of the auto cleaning cycles."
    • Gary Cay states: "My observational (not measured) experience is that turning the printer OFF uses less ink and avoids unnecessary cleanings which in fact do add up, albeit they are small. Until one of us figures out how to measure ink use and actually does it, this is a working hypothesis only and not a fact. However, this is my working hypothesis after 5.5 months of living with this printer." The downside of this approach is that sometimes upon turning printer on it would clean for 5 minutes.

Summary: Some users report less apparent ink usage if printer is turned off, while others found that leaving the printer on (in standby mode) worked better for them. You may need to experiment to find what works best for you.

Update 9/22/07: A report by Tom Huxley suggests it may be best to leave the printer turned on. For his iPF5000, he found 2.9 ml per day was used when the printer was in standby mode, but the printer used a much larger amount when turned off for a couple of weeks. The figure of 2.9 appears to be fairly accurate, and was confirmed by another poster in an FAQ on ink used for cleaning. Don't be alarmed by the amount of ink used when the printer was turned off, as many are not reporting anything like this kind of ink usage.