Bosch Greensource SM024 Installation, Operation And Maintenance Manual page 15

SM AH Series Heat Pump | 15
5. Periodic lockouts almost always are caused by
air or water flow problems. The lockout
(shutdown) of the unit is a normal protective
measure in the design of the equipment. If
continual lockouts occur call a mechanic
immediately and have them check for: water
flow problems, water temperature problems,
air flow problems or air temperature problems.
Use of the pressure and temperature charts for
the unit may be required to properly determine
the cause.
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