The adjustable magnetic dirt-separator allows for the collection of dirt and debris from the circulating heat transfer fluid within heating systems. The dirt particles, debris and ferromagnetic residues, are partly released from scale deposits in the heat transfer fluid and partly generated by corrosive phenomena occurring on the surfaces of certain components of the system. The adjustable magnetic dirt-separator protects and maintains all the components in the system at maximum efficiency by separating impurities. The pressure drops of the dirt separator does not change over time, as the quantity of accumulated particles does not affect the device’s performance. Thanks to this peculiar characteristic, its use is particularly suitable for heat pump systems. Available with or without insulation.