Problems on this page:
Overrun out of specification
Hits OEE: Quality
Symptoms: The air content of the ice cream is too high or too low, so the pack weight or the texture is wrong.
Air flow setting wrong for the recipe
Check the air flow setting against the recipe and the flow meter reading.
Mix pump output changed
Check the mix pump speed and the actual flow, since overrun depends on the ratio of air to mix.
Back pressure at the outlet changed
Check the back pressure valve setting and that it is not sticking.
Mix temperature or ageing different from usual
Check the mix temperature at the freezer inlet and the ageing time in the tanks.
Prevention: Overrun measured at set times on every run.
Ice cream too soft at the outlet
Hits OEE: Quality
Symptoms: Product leaves the freezer warmer and softer than set, and shapes or fills poorly.
Refrigeration not reaching the set point
Check the refrigerant supply and the evaporating pressure in the cylinder jacket.
Mix flow too high for the freezer
Reduce the mix flow to the rate the freezer can handle for this recipe.
Scraper blades worn
Replace worn blades, because ice left on the cylinder wall stops heat transfer.
Mix entering too warm
Check the mix temperature leaving the ageing tanks.
Prevention: Outlet temperature recorded continuously.
Freezer overloading
Hits OEE: Availability
Symptoms: The dasher motor reaches its limit and the freezer stops.
Product drawn too cold and stiff
Raise the outlet temperature setting slightly for stiff recipes.
Large inclusions entering the cylinder
Add large pieces after the freezer with an ingredient feeder, not into the cylinder.
Bearings or seals dragging
Turn the dasher by hand with the freezer isolated and feel for drag.
Back pressure set too high
Check the outlet valve setting.
Prevention: Dasher motor load trended per recipe.
Coarse, icy texture
Hits OEE: Quality
Symptoms: Ice cream feels icy or grainy when tasted, sometimes only after storage.
Scraper blades worn
Replace the blades so the cylinder wall is scraped clean on every turn.
Freezing too slow in the cylinder
Check the refrigeration capacity and the evaporating pressure.
Temperature swings in hardening or storage
Check the hardening tunnel and cold store temperature records.
Stabiliser or formula changed
Check the mix recipe and ingredient lots with quality.
Prevention: Texture checked by a tasting panel on each product.
Cylinder freezing up
Hits OEE: Availability
Symptoms: Product freezes solid in the cylinder and the dasher cannot turn.
Mix flow stopped while refrigeration kept running
Make sure refrigeration to the cylinder stops whenever the mix stops.
Stop sequence not followed
Write the stop sequence at the freezer and train every operator on it.
Refrigerant control valve sticking open
Have the valve serviced by refrigeration staff.
Mix flow brought up too slowly at start-up
Start the mix flow before full refrigeration, as the start sequence sets.
Prevention: Start and stop procedure posted at the freezer.
Overrun unstable
Hits OEE: Quality
Symptoms: Overrun swings up and down during a run even though the settings did not change.
Air leaking at fittings or the air line
Check the air line and fittings with the freezer running.
Air supply pressure varying
Check the air regulator and filter.
Mix pump wearing
Have the mix pump serviced when its output varies.
Back pressure valve sticking
Clean and service the back pressure valve.
Prevention: Overrun trended through each run.
Shaft seal leaking
Hits OEE: Quality
Symptoms: Mix leaks at the dasher shaft seal.
Seal faces worn
Replace the seal at the interval the maker sets.
Seal assembled wrongly after cleaning
Follow the assembly instructions and check the seal before starting.
Shaft surface worn
Check the shaft where the seal runs.
Seal flush not running
Check the seal flush supply.
Prevention: Seal checked after every clean.
Cleaning results failing
Hits OEE: Quality
Symptoms: Hygiene swabs or rinse checks fail after cleaning.
Cleaning temperature too low
Check the cleaning solution temperature at the freezer, not only at the tank.
Detergent strength low
Check the concentration before each clean.
Parts not dismantled as required
Dismantle the dasher, blades and valves as the cleaning procedure lists.
Cleaning flow too low
Check the flow rate through the cylinder.
Prevention: Swab results trended per freezer.
Refrigerant control unstable
Hits OEE: Availability
Symptoms: Cylinder pressure and outlet temperature swing during the run.
Control valve wearing
Have the control valve serviced.
Liquid level control faulty
Have the level control checked.
Oil collecting on the refrigerant side
Have oil drained as the plant procedure sets.
Plant short of capacity at peak load
Check what else draws on the refrigeration plant at the same time.
Prevention: Pressures logged; only trained refrigeration staff work on the plant.
Guidance only. Always follow lockout/tagout and your site's safe-work procedures, and verify against OEM manuals before acting.
Related equipment guides: homogeniser · HTST pasteuriser · spiral freezer · refrigeration compressor · CIP system
Stop the same fault coming back
Recurring continuous ice cream freezer stops usually trace to a cause you cannot see by hand. The partner we recommend is Fabrico: it tracks OEE and downtime live from PLCs, IoT sensors or AI cameras; where cameras are fitted, the video of a stop sits next to its machine data so the cause can be reviewed; and a technician opens the work order from the stop in the same system. Data is hosted in the AWS EU region, and Fabrico and the company behind it hold ISO/IEC 27001, ISO/IEC 20000-1 and ISO 9001.
Book a Fabrico demo
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Related tools: full troubleshooting directory · OEE calculator · downtime cost · MTBF / MTTR · glossary
Methods that cut recurring stops: the six big losses · root cause analysis · preventive vs predictive maintenance · TPM · SMED & changeover