Charging Unit after APR Control Installation.
After properly installing an APR Control a unit should be charged to the factory recommended specifications, the installation of the APR Control does not require additional refrigerant. During the charging process in order to maintain accurate pressure readings the manual shut off valves at the APR Control connection points should remain closed, this will prevent the APR Control from attempting to modulate during the charging process.
With the manual shut off valves at the APR Control connections closed, follow equipment manufacturer’s start up procedures to ensure the unit is operating properly. Once it is determined the unit is operating properly, open the manual shut off valves to bring the APR Control into the circuit.
In order to test operation of the APR Control there must be a reduction in suction pressure. To simulate this process restrict the airflow across the evaporator coil just enough to lower the suction pressure below the desired suction pressure setpoint of the APR Control. At this point the APR Control will attempt to stabilize the suction pressure. For more information see our Installation page: https://www.rawal.com/technical/installation/