If the last descaling date is missing, don’t pick an interval from another cafe’s calendar. Find the machine model, its maintenance instructions and the last water-treatment record. Those give a technician something useful to work from.
The same applies to a busy cafe. More drinks alone do not tell you how much scale is inside the steam boiler, or whether an internal descale is the next required job.
Cleaning the group is a different job
The La Marzocco Linea PB manual separates routine group cleaning from technician maintenance and internal boiler inspection. A completed backflush cleans the group through its specified cleaning circuit. It is not a record that the boiler has been inspected or descaled.
Keep those entries separate in the service log. Write down the cleaning procedure staff completed, then retain the technician’s findings about the boiler and water system. If an invoice says only “cleaned,” ask which work that covered.
Use a water test, not a city label
La Marzocco’s water requirements list hardness, alkalinity, dissolved solids and other parameters separately. Its preventive-maintenance checklist records water before and after filtration. That is a better basis for the next service decision than calling all Bay Area water hard or soft.
Ask the water-treatment provider for the current test results and the cartridge’s service record. If the water supply or treatment changes, pass that information to the machine technician. A new cartridge does not document the condition of a boiler that was already in use.
For cartridge timing, see how to track a water filter’s replacement date and capacity.
What to do when performance changes
Record whether the problem affects steam, brewing or both. A weak wand and a cold boiler are different complaints. The Linea PB troubleshooting section also distinguishes filling, probe and heating faults; a symptom by itself is not a scale diagnosis.
If performance stays poor after the operator cleaning procedure, arrange diagnosis. Repeating a chemical treatment without knowing the cause is not a maintenance plan. Keep the machine out of use if it leaks, overheats or has an electrical fault.
Who should do the descale
Follow only the procedure assigned to the operator in the exact machine manual, using its specified product and rinse instructions. If the manual assigns the work to service personnel, leave it there. Boiler opening, heating components and pressurized fittings are technician work.
At the next service, ask for a written record of the water results, observed condition, work completed and the next check. That makes the schedule specific to this machine.
Sources: La Marzocco Linea PB manual and preventive-maintenance documents, manual PDF pages 13, 21–24 and 135; Linea PB preventative maintenance, 12 month checklist, version 2.1, May 2026, page 1. These are model examples, not a maintenance interval for other equipment.