Details of boiler during the second oldest lockout still in memory
The Lockout History 2 error code on Weil-Mclain boilers indicates details of boiler during the second oldest lockout still in memory.
Weil-Mclain Lockout History 2 means: details of boiler during the second oldest lockout still in memory. The usual cause is details of boiler during the second oldest lockout still in memory. You can safely reset the boiler once — if Lockout History 2 returns, do not keep resetting. A qualified heating engineer should diagnose the root cause.
What Does Lockout History 2 Mean
The Lockout History 2 code is shown by the boiler’s control board when it detects details of boiler during the second oldest lockout still in memory. The boiler then stops instead of continuing to run in that condition: the code is the appliance reporting a problem, not proof that the boiler is broken.
| What you see on the boiler |
|---|
| The display shows Lockout History 2 and the boiler stops until the fault is cleared |
Common Causes
Causes documented in the Weil-Mclain service literature published by weil-mclain.com, cross-checked against the manufacturer’s fault-code table.
| Cause |
|---|
| Details of boiler during the second oldest lockout still in memory |
Safety Warning
Lockout History 2 involves electrical or pressure-related components. Do not attempt repairs without proper qualifications. Ensure the boiler is electrically isolated before any inspection. If you notice water leaks, unusual sounds, or pressure anomalies, contact a qualified heating engineer immediately.
Parts & Prices
Prices shown are indicative. Actual prices and availability vary by region.
How to Fix It
Select and press the enter key for more details
Refer to the Weil-Mclain service documentation for the detailed procedure. Only a qualified engineer should carry out these repairs.
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Affected Models
Weil-Mclain models that can display fault code Lockout History 2:
| Model Family | Output Range | Frequency |
|---|---|---|
| All Weil-Mclain models | — | Possible |
Frequently Asked Questions
Select and press the enter key for more details. According to the technical documentation, this is the first check on the list for Lockout History 2.
Lockout History 2 is not classified as a high-severity fault, so the boiler can be reset once. If Lockout History 2 comes back, stop resetting: the underlying cause is still there and needs a qualified heating engineer.