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Danfoss AVTB (fast) Self-Acting Temperature Controller DN 25 20–60 °C

Danfoss · HVAC & Refrigeration · Water Regulating Valves · Denmark · danfoss.com
Part Number
003N8252  ·  HS 8481.80
Danfoss AVTB (fast) Self-Acting Temperature Controller DN 25 20–60 °C

Danfoss AVTB (fast) self-acting temperature controller, OEM P/N 003N8252. Proportional self-acting controller that regulates water temperature in district heating and cooling circuits; a remote 2 m capillary and charged sensor (Ø 9.5 mm × 180 mm) sense the medium temperature and throttle the valve, with a 3-second reaction time (fast version). DN 25, PN 16, internal thread NPT 1 in. Kvs 5.5 m³/h; temperature setting range 20 – 60 °C, linear characteristic. Brass body (CuZn40Pb2), NBR valve cone, Cr Ni steel valve seat, copper impulse tube and sensor. Max differential pressure 10 bar; media temperature 2 – 130 °C, max sensor temperature 90 °C. Approved to ETA VA 1.54/18952. Confirm the setting range and code against the datasheet before ordering.

Technical Specifications

BrandDanfoss
Part number003N8252
ModelAVTB (fast) self-acting temperature controller
CategoryHVAC & Refrigeration — Water Regulating Valves
Versionself-acting proportional controller, remote capillary sensor, fast response, internal thread
Functiontemperature controller; charged sensor throttles the valve to hold the set medium temperature
Nominal sizeDN 25
Pressure classPN 16
Connectioninternal thread NPT 1 in
Kvs5.5 m³/h
Temperature setting range20 – 60 °C
Flow characteristiclinear
Max differential pressure10 bar
Media temperature range2 °C to 130 °C
Max sensor temperature90 °C
Ambient temperature range0 °C to 70 °C
Capillary tube length2 m
SensorØ 9.5 mm × 180 mm
Reaction time (open/close)3 s; time constant 3 s
Cavitation factor0.4
Mounting versionreturn
Body materialbrass CuZn40Pb2
Valve cone materialNBR rubber
Valve seat materialCr Ni steel
Impulse tube materialcopper
Applicationdistrict heating / cooling circulation water; glycolic water up to 30%
PackingSingle pack
EAN5702421101469
ApprovalsETA VA 1.54/18952, EAC, PED, EU RoHS, China RoHS

Properties

MaterialBody brass CuZn40Pb2; valve cone NBR rubber; valve seat Cr Ni steel; impulse tube copper
Pressure ratingPN 16; max differential pressure 10 bar
Temperature range2 °C to 130 °C (media); max sensor 90 °C
Standard sizeDN 25
Thread standardANSI/ASME B1.20.1 (NPT)
MOQ1

Compatibility

Mount the valve body in the water line (return version) and locate the sensor where it reads the controlled medium; the 2 m capillary connects the two. Self-acting (no external power). Set the temperature on the adjustment spindle. Confirm code and setting range before ordering.

Standards

Approvals

Attached Documents