4 sourced reports, with what to check before you buy. Each one links to the page it was reported on.
Costly or dangerous
K1 head PCB (nozzle board) failure stops extrusion mid-print
An owner reports the K1 stops extruding mid-print at the same height; replacing the hotend and extruder motor did not help, and the fix was replacing the head PCB. This is a first-hand owner account on a French 3D printing forum.
What to check. If a K1 stops extruding mid-print at a consistent height and a hotend swap does not fix it, suspect the nozzle/head board rather than a clog. This is a board-level electrical failure, not a user-tunable setting.
K1 firmware can be bricked; official wire-flash recovery procedure
Creality's own wiki publishes a 'brick rescue / wire-flash' procedure for the K1 series, which is official acknowledgement that the firmware can be bricked and must be recovered by flashing the board over USB.
What to check. Creality maintains a wire-flash recovery procedure for bricked K1 units, so a bad firmware update is recoverable but requires opening the machine and flashing the mainboard. Treat firmware updates as risky and follow the official recovery path if it fails.
K1 reliability and first-layer complaints from verified buyers
Verified-purchase customer reviews on retailer Alza.cz report constant tuning, unreliable auto-leveling, and difficulty getting a good first layer; one unit 'lasted a month' (low endurance).
What to check. Multiple verified buyers describe the K1 as needing constant tuning and report poor first-layer adhesion and short-lived units. Budget for setup time and possible early failure.
K1 owner reports persistent Error 2522 on a new unit
An owner on Creality's own cloud forum reports a new K1 repeatedly showing Error 2522 and asking whether the printer is defective. This is a first-hand report of a specific error code on a new unit.
What to check. A new K1 showing Error 2522 is a reported failure mode; owners should check Creality's error-code list and contact support rather than assume it is user error.
These reports come from the pages linked under each item: owner forums, repair guides and workshops. They are not a diagnosis of any one unit, and a careful check of the one you are buying still applies.
Text from the Kriko 3D printers catalog, version 0.1.1, under the CC-BY-SA-4.0 license.
