Hobart Legacy+ Mixer Error OL1 / OL2 / OLU: Thermal Overload
OL1, OL2 and OLU mean the electronic thermal overload on a Hobart Legacy+ HL800 or HL1400 mixer drive has tripped, so the drive thinks the motor is overloaded. Stop the mixer, use Speed 1 or 2 for mixing instead of Stir speed, and reduce the batch size before cycling power. If OL comes back on a light batch, call us.
Medium: the mixer stops until power is cycled, and the cause is often how the batch or speed was chosen.
What does Hobart error code OL1 / OL2 / OLU mean?
Besides measuring instant current, the drive keeps a running estimate of how hard the motor has been working over time. That estimate is the electronic thermal overload. When the motor carries too much load for too long, the estimate passes its limit and the drive stops the motor, showing OL1, OL2 or OLU on the SmartTimer. The mixer will not restart until power is cycled and the cause is corrected. The usual cause is how the mixer was used: Stir speed is not meant for dough or other heavy product, and a batch that is too large for the speed keeps the motor working hard. Low supply voltage makes it worse, as does a drive ambient temperature above 122 F. A bowl, beater or agitator that drags adds load that the operator may not notice. Overload can be a real load, a hot room or a weak supply, and the display cannot tell which. The display text is OL1 / OL2 / OLU. A drive that trips on normal batches may need testing before the next heavy day.
Affected models and control systems
Hobart Legacy+ HL800 and HL1400 mixers with the motor drive and SmartTimer display. The three codes share one meaning.
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
- OL1, OL2 or OLU on the SmartTimer display
- Mixer stops after a long mix or stiff dough
- Mixer slow to restart after cooling
Possible causes
Listed in Hobart's documentation
- Speed and batch size used when the code appeared
- Low supply voltage under load
- Drive ambient temperature above 122 F
- Bowl, beater or agitator condition and anything dragging
Other likely causes — what usually sits behind error code OL1 / OL2 / OLU on this control. A technician confirms which one it is before any part is replaced.
- Stir speed chosen for a stiff product during a rush
- A beater or bowl guide with a worn bearing that adds drag
Safe checks before calling for service
- Stop the mixer and leave the guard shut.
- Select Speed 1 or 2 for mixing, since Stir speed is not meant for dough or other heavy product.
- Reduce the batch size, then cycle power.
- If OL comes back on a light batch, stop and call us.
- Tell us the product, batch size and speed used.
How a technician diagnoses error code OL1 / OL2 / OLU
- Read the code and ask about product, batch size and speed.
- Measure supply voltage under load at the mixer.
- Check room and drive temperature against the 122 F limit.
- Turn the bowl and agitator by hand with power off to feel for drag or binding.
- Check motor current against the nameplate during a normal batch.
- Replace the drive or motor only after load, supply and ambient heat are cleared.
- Measuring motor current under load is live work on 208 to 240 V circuits.
- The display cannot tell whether a real load, a hot room or a weak supply caused the overload.
- We check supply and ambient heat first, then the drive and motor.
Technical reference
- Document
- Large Capacity Mixers Customer Maintenance Manual F48065 (10-22), Diagnostic Error Codes
- Maker documentation
- Hobart owner support
- Edition
- F48065
- Models / control
- Legacy+ HL800 / HL1400 motor drive + SmartTimer display
- Section
- Diagnostic Error Codes HL800 & HL1400, PDF pp. 9-11
- 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 Hobart mixer error codes
What is Stir speed for?
Light stirring only. The manual says to use Speed 1 or 2 for mixing.
Why does it trip on a normal batch?
A weak supply, a hot room or a dragging bowl or beater can overload it.
Is OLU different from OL1?
They share one meaning, thermal overload tripped.
Need help with Hobart error code OL1 / OL2 / OLU?
A technician confirms the cause on site and gives you the price in writing before any work starts.