Error code
51 Low-pressure alarm
Applies to 1 model
F730
What this means
The heat pump has detected low pressure in the refrigerant circuit. This is a fault requiring investigation; the display may show "Lågtryckslarm" and alarm 51.
When to call a technician
This fault involves refrigerant, pressure, or electrical work that must be handled by a certified technician under EU F-gas rules. Do not attempt to open the refrigerant circuit, access mains wiring, or adjust pressure components yourself. Contact a qualified installer or servicer for this one.