Koolaire Ice Machine Safety Limit 2: Harvest Reached 3.5 Minutes
Safety Limit 2 means the machine has had repeated harvest cycles of 3.5 minutes. The SL#2 light flashes after 3, stays on after 75, and the machine stops after 100 consecutive. Press On/Off and start a new ice making cycle to reset it.
Medium: a staged warning that only stops the machine after 100 consecutive long harvests.
- Code
- Safety Limit 2 (SL#2 light)
- Maker
- Koolaire
- Equipment
- Ice machines
- Applies to
- Koolaire KT series control board
What does Koolaire Safety Limit 2 mean?
Harvest is the short step where the evaporator warms and the ice slides off. The control board counts how many consecutive harvest cycles last the full 3.5 minutes. After 3 in a row, the SL#2 light on the control board flashes at 1-second intervals (Safety Limit 2). After 75, the light stays on. After 100 consecutive 3.5-minute harvests, the machine stops with SL#2 lit. The staged warning lets an operator catch it long before the machine stops. The manual lists no individual causes in this section. It gives the same reset as for the other safety limits: press the On/Off button and start a new ice making cycle. Its troubleshooting page says to switch OFF and then ICE, and to call for service if the condition repeats. A harvest that always runs to its limit suggests the ice is slow to release.
Affected models and control systems
Air-, water- and remote-cooled Koolaire KT series ice machines, including the KDT and KYT 0300A through 1700.
Code numbers and their meaning can change between control generations. We match the full model and control before acting on a code.
What you may notice
- SL#2 light flashing at 1-second intervals
- SL#2 light staying on
- Machine stopped with SL#2 lit
Possible causes
Likely causes — what usually sits behind Safety Limit 2 on this control. A technician confirms which one it is before any part is replaced.
- Scale on the evaporator surface holding ice so the harvest runs to its limit
- A harvest valve that does not open fully, so the evaporator warms slowly
- Water too cold, slowing release of the ice slab
Safe checks before calling for service
- Press the On/Off button and start a new ice making cycle.
- Notice whether the light flashes again soon after or stays off for days.
- Check that the ice machine area is not extremely cold.
- If SL#2 returns, tell the technician whether it was flashing or solid.
How a technician diagnoses Safety Limit 2
- Read the light state, which shows how many harvests hit the limit.
- Time a harvest cycle and watch how the ice releases.
- Check the evaporator for scale and the water distribution.
- Test the harvest valve and its coil.
- Check supply pressure and incoming water temperature.
- The harvest valve is part of the sealed refrigerant circuit.
- Valve coils run on line voltage.
- Descaling uses chemicals around food-contact surfaces.
How Safety Limit 2 differs from similar codes
Safety Limit 1 is about 60-minute freeze cycles; Safety Limit 2 is about 3.5-minute harvest cycles.
Technical reference
- Maker documentation
- Koolaire owner support
- Edition
- Part Number 000014142 Rev 04 07/22
- Models / control
- Koolaire KT series control board
- Section
- Section 3 Operation, Safety Limits (p. 27); Section 5 Troubleshooting, Safety Limit Feature (p. 41)
- Checked
- October 2026
We use the maker's document to read the code and do not reproduce it. Always confirm the complete model and control before applying these steps.
Related Koolaire ice machine error codes
What do the flashing stages mean?
The light flashes after 3, stays on after 75, and the machine stops after 100.
Is SL#2 an emergency?
No, it is a long warning, but it should be investigated.
How do I reset it?
Press On/Off and start a new ice making cycle.
Need help with Koolaire Safety Limit 2?
A technician confirms the cause on site and gives you the price in writing before any work starts.