--- title: Sapiens - How do you solve the error message “A64 boiler temperature alarm”? description: A64 Boiler high temperature alarm warn that boiler temperature exceeds 150°C/302°F. As consequence unit deactivate the boiler. 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[Home](https://support.lainox.com/en/knowledge) 2. [Sapiens](https://support.lainox.com/en/knowledge/sapiens) 3. [Messages](https://support.lainox.com/en/knowledge/sapiens#messages) # Sapiens - How do you solve the error message “A64 boiler temperature alarm”? A64 Boiler high temperature alarm warn that boiler temperature exceeds 150°C/302°F. As consequence unit deactivate the boiler. **This message requires the intervention of an authorized technician; causes of the fault must be investigated as per prescriptions**. ### Description Probe SB detect a temperature equal or above 150°C/302°F. ### Reset Errer reset automatically when temperature decrease below treshold. ### Checks Perform following checks: - Check current on supply lines; with unit in standby has to be 0A - Check C6 contacts have to stay open when unit is off; in case replace C6. - Check C4 and C5 (C3 for small units) contacts has to stay open when unit is off or in standby; in case replace them. - Check boiler status and no limescale presence. - Check level electrodes status. - [Naboo](https://support.lainox.com/en/knowledge/naboo#main-content) - [Installation](https://support.lainox.com/en/knowledge/naboo#installation) - [Use](https://support.lainox.com/en/knowledge/naboo#use) - [Messages](https://support.lainox.com/en/knowledge/naboo#messages) - [How to](https://support.lainox.com/en/knowledge/naboo#how-to) - [How it works](https://support.lainox.com/en/knowledge/naboo#how-it-works) - [Sapiens](https://support.lainox.com/en/knowledge/sapiens#main-content) - [Installation](https://support.lainox.com/en/knowledge/sapiens#installation) - [Use](https://support.lainox.com/en/knowledge/sapiens#use) - [Messages](https://support.lainox.com/en/knowledge/sapiens#messages) - [How to](https://support.lainox.com/en/knowledge/sapiens#how-to) - [How it works](https://support.lainox.com/en/knowledge/sapiens#how-it-works) - [Neo24hours](https://support.lainox.com/en/knowledge/neo24hours#main-content) - [Installation](https://support.lainox.com/en/knowledge/neo24hours#installation) - [Use](https://support.lainox.com/en/knowledge/neo24hours#use) - [Messages](https://support.lainox.com/en/knowledge/neo24hours#messages) - [How to](https://support.lainox.com/en/knowledge/neo24hours#how-to) - [How it works](https://support.lainox.com/en/knowledge/neo24hours#how-it-works) - [Oracle](https://support.lainox.com/en/knowledge/oracle#main-content) - [Installation](https://support.lainox.com/en/knowledge/oracle#installation) - [Use](https://support.lainox.com/en/knowledge/oracle#use) - [Messages](https://support.lainox.com/en/knowledge/oracle#messages) - [How to](https://support.lainox.com/en/knowledge/oracle#how-to) - [How it works](https://support.lainox.com/en/knowledge/oracle#how-it-works) - [Puff](https://support.lainox.com/en/knowledge/puff#main-content) - [Installation](https://support.lainox.com/en/knowledge/puff#installation) - [Use](https://support.lainox.com/en/knowledge/puff#use) - [Messages](https://support.lainox.com/en/knowledge/puff#messages) - [How to](https://support.lainox.com/en/knowledge/puff#how-to) - [How it works](https://support.lainox.com/en/knowledge/puff#how-it-works) - [Zoom](https://support.lainox.com/en/knowledge/zoom#main-content) - [Installation](https://support.lainox.com/en/knowledge/zoom#installation) - [Use](https://support.lainox.com/en/knowledge/zoom#use) - [Messages](https://support.lainox.com/en/knowledge/zoom#messages) - [How to](https://support.lainox.com/en/knowledge/zoom#how-to) - [How it works](https://support.lainox.com/en/knowledge/zoom#how-it-works) [![Chill listening crop-3](https://support.lainox.com/hs-fs/hubfs/LAINOX-1.png?width=88&height=24&name=LAINOX-1.png "Chill listening crop-3")](https://lainox.com/) Copyright © 2026, LAINOX Ali Group S.r.l. a Socio Unico