Danfoss ASV-PV 4G — self-acting differential-pressure controller (4th generation), OEM order code 003Z5552. Fourth-generation self-acting (automatic) differential-pressure controller for automatic hydronic balancing. Installed in the return of a riser and connected by an impulse tube to an ASV-BD/ASV-M partner valve on the supply, it holds a constant differential pressure across the riser regardless of load changes elsewhere in the system. Constant differential pressure keeps two-way control-valve authority high and prevents flow noise at part load. Integral shut-off; adjustable setting range. (ASV-PV DN 20, 20-60 kPa, External thread, without insulation, automatic balancing valve.) Nominal size DN 20, Kvs 2.5 m³/h, PN 16, External Thread connection, Brass body, media temperature 0 °C to 120 °C. Differential-pressure setting range 20-60 kPa (factory setting 30 KPa), max. differential pressure over the valve 250 KPa, impulse tube 1.5 m. Net weight 1.07 Kilogram. Genuine Danfoss part; technical data quoted verbatim from store.danfoss.com (code 003Z5552). OEM P/N 003Z5552, EAN 5710104086286. Used in commercial refrigeration, provision-room cooling and reefer plant rooms across HFC, HFO and CO2 (R744) refrigerants.