Heat pumps · Error codes · Ochsner
Er242Ochsner · OTE 3 / OTE 4 controller fault platform (error-code grouping)
Er242 on an Ochsner OTE 3 / OTE 4 controller fault platform: Communication malfunction CAN bus
Short answer
On an Ochsner heat pump, Er242 means: Communication malfunction CAN bus. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Communication malfunction CAN bus.
Part involved: Communication malfunction CAN bus.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
What you can check
- Note the Er number and text and contact your OCHSNER system partner.
What the engineer will check
- Check Modbus/CAN bus wiring and module addressing.
Who to ask for: OCHSNER service partner.
What you might notice
Sources
- OCHSNER Heat Pump Control OTE 3 / OTE 4 Operating Instructions (V03, 2017-07-26) ↗ · V03 · page 46 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026