ISA is a high-end Italian manufacturer of pastry, gelato, and chocolate display cabinets. Many upscale UK patisseries use ISA showcases (e.g. the ISA Millennium series). These units have advanced controllers to manage temperature and often humidity for chocolate. Common issues are similar – sensor faults and temperature alarms – though ISA’s build quality means failures often tie to external factors (environment, maintenance).
Typical Faults & Diagnosis: ISA displays are designed to hold precise temperature; if temperature is not sufficiently low as needed, the user section of ISA’s manuals suggests a few causes: evaporator completely blocked with ice (needs defrost), wrong temperature setpoint (adjust to proper value), or appliance affected by drafts or sunlight which warms the glass and interior. Thus, ensure there are no AC vents blowing warm air into the display and it’s out of direct sun. Also check for airflow to the condenser – ISA notes that insufficient airflow (e.g., papers or dust blocking the grille) will impair cooling. Clean any dust from the front grill and condenser. If the compressor isn’t starting or runs only briefly, one cause could be excessively low supply voltage (ensure your supply is a steady 230V ±10%). Also, ISA controllers will not run the compressor if the set temperature is higher than the current cabinet temp (to prevent over-cooling) – for example, if you mistakenly set the fridge to 18 °C for chocolate, the compressor will stop if the cabinet is already at 15 °C. Verify the setpoint is appropriate (usually ~4 °C for cakes, ~14 °C for chocolate).
On the technical side, if issues persist, ISA provides an after-sales technical checklist: Internal fans not working will cause uneven cooling – replace any failed fans. A faulty thermostat or electronic board can cause temperature problems – ISA advises to replace them if they’re “not efficient” (this should be done with original parts due to R290 refrigerant safety). A dirty condenser (“condensing unit blocked with dust”) is reiterated as a cause for poor performance, requiring thorough cleaning. Low refrigerant (a leak) will also result in insufficient cooling – you’d notice the compressor running constantly without reaching temperature; a certified engineer would need to repair the leak and recharge the system.
ISA’s digital controller will show error codes for probe failures just like others. For instance, the ISA LABOR series manual shows E1 for a broken cabinet probe and E2 for a faulty evaporator probe. Additionally, some ISA models (like ISA Isabella) note that “the alarm signal deriving from a faulty evaporator probe appears with indication E2”. So expect E1/E2 codes for sensor issues on ISA displays – handle these by checking connections and replacing the sensor if confirmed bad.
Fault Code Table – ISA: (Typical for ISA digital controls, e.g., Eliwell)
| Code | Meaning | Solution |
|---|---|---|
| E1 | Probe 1 (cabinet) fault | Cabinet temp probe reading out of range (open or short). Action: Check probe connection; replace if faulty. The controller may display this as a blinking alarm and keep compressor running in a safe mode. |
| E2 | Probe 2 (evaporator) fault | Defrost probe failure. Action: Inspect/replace evaporator sensor. Manual defrost the unit and monitor – after new probe, normal defrost control resumes. |
| P2 | (On some models) Parameter for probe error | Some ISA manuals use “P2” to denote a probe alarm in diagnostics. Essentially similar to E1/E2 depending on context. Action: Refer to model-specific code legend; usually means a probe broke or reading impossible – replace the indicated probe. |
| HA / LA | High Alarm / Low Alarm | Cabinet temp exceeded the High or Low threshold set in controller. Action: Treat as temperature alarms – check if product loading, ambient heat, or a fault caused extreme temp, and resolve it. Alarm resets when temp is back in range. |
| DEF | Defrost active (indicator) | The unit is in a defrost cycle (not a fault). Action: None; normal operation. If stuck in DEF, check defrost sensor (could indicate an E2 issue if defrost never terminates). |
Maintenance Tip: ISA’s maintenance schedule (often in Chapter 12 of their manuals) calls for regular tasks like cleaning the condenser filter, checking door seals, and replacing LED lamps if needed. Adhering to these maintenance tasks will prevent most faults. Given the premium nature of ISA units, don’t bypass safety alarms – for any persistent error (especially sensor or pressure alarms), it’s best to contact HTG/ISA’s official service in the UK.