Protection Menu / 8.1 - Flow Protection

Flow protection is one of the most important protective functions of a heat pump and protects the heat exchanger from damage during flow loss. A flow loss triggers an error message and stops the operation of the outdoor unit. A flow loss during defrosting can cause the heating water in the heat exchanger to freeze, resulting in permanent damage.

The flow can be monitored by one of two inputs, or even a combination of both (if necessary).

– when this option is selected, the flow is monitored based on the closed contact of S1, to which the flow switch is connected with factory preset flow cut-off and turn-on thresholds. A flow loss detected by the S1 flow switch will trigger the error message FS.

– the heating water flow can also be monitored using a flow sensor, which precisely determines the water flow rate. The sensor is connected to the connector I1 and, depending on the type of sensor chosen, it must be calibrated. It is also possible to select the lower flow limit. If the flow falls below this limit, MiniHPC stops the compressor and displays an error message. A flow loss detected by the I1 flow sensor will trigger the error message FI.

is the period that is counted down after any change in the state of relays R3, R4, or R5. During this period, a flow loss is not treated as an error. The purpose of this setting is that any switching of the 3-way valve may cause a brief flow loss during state transitions. This time should be adjusted so that it does not exceed the switching time of the 3-way valve.