Danfoss T 2 Thermostatic Expansion Valve (068Z3808) – R452A, Internal Equalization, Flare Inlet × 12 mm Solder Outlet

Danfoss T 2 (code 068Z3808) is an internally equalized thermostatic expansion valve (TXV) calibrated for R452A refrigerant. It continuously adjusts the amount of liquid sent to the evaporator according to the suction line superheat measured by the sensor; this way the evaporator is fully fed but no liquid reaches the compressor.

Calibrated for R452A: The R404A Successor in Transport and Commercial Refrigeration

R452A is a low-GWP HFC/HFO blend that replaces high-GWP R404A and has become widespread especially in transport refrigeration (refrigerated vehicles, containers) and commercial refrigeration. Because its pressure-temperature curve is close to that of R404A, it is used in mechanically similar systems — however, the thermostatic element of the expansion valve is charged specifically for the refrigerant. This valve is factory-charged to the R452A curve; an R404A valve does not give the correct superheat in an R452A system.

Internal equalization (T 2) is suitable for single-circuit evaporators without a distributor, where the pressure drop in the evaporator is low. If your system has a liquid distributor or the evaporator pressure drop is high, the externally equalized TE 2 model should be chosen instead of an internally equalized valve — this is Danfoss's explicit recommendation.

Technical Specifications (Official Danfoss Data Sheet)

• Model: Danfoss T 2 | Code: 068Z3808
• Type: Thermostatic expansion valve, internally equalized, with interchangeable orifice assembly
• Refrigerant: R452A (factory charge is refrigerant-specific)
• Evaporating Range: −40 … +10 °C (Range N) | MOP: none
• Connections: Inlet flare × Outlet 12 mm ODF solder — metric 10×12 mm body
• Max. Working Pressure: PS/MWP 34 bar | Test pressure PT 38 bar
• Temperature Limits: Min. −60 °C | Sensor max. 100 °C (with valve fitted), 60 °C (with element removed)
• Capillary Tube: 1.5 m | Sensor: Ø14.5 × 50 mm, Danfoss patented sensor clamp included
• Superheat: Static SS = 4 K (adjustable with the adjusting spindle) · Opening OS = 6 K
• Body Dimensions: 35 + 54 mm width · 30 + 35 mm height | Weight: 0.3 kg — official dimension drawing in the 2nd image
• Durability: Resistant to the effects of hot gas defrost; valve cone and seat made of a special wear-resistant alloy

Capacity — By Orifice Assembly (R452A, 25 °C condensing)

The valve is sold as a body; the orifice assembly is separate; the orifice number determines the capacity. The values below apply at −10 °C evaporating:

• NO: 0X → 0.70 kW  ·  NO: 00 → 1.29 kW  ·  NO: 01 → 2.35 kW  ·  NO: 02 → 2.98 kW
• NO: 03 → 5.04 kW  ·  NO: 04 → 7.60 kW  ·  NO: 05 → 10.0 kW  ·  NO: 06 → 12.0 kW
• Whole series band: 0.49 – 17.8 kW (depending on condensing and evaporating temperature). Orifice assemblies are available separately on our website.

• 🔧 Clamp the sensor to the suction tube at the 3-4 o'clock position and insulate it; do not mount it on top of the tube (12 o'clock), as the oil film gives a false reading.
• Cool the body with a wet cloth while brazing and purge with nitrogen — the thermostatic element charge and the orifice filter are damaged by excessive heat.
• Order the orifice assembly separately: If the NO matching your system capacity is not selected, the valve either stays too open (liquid carry-over) or throttles (capacity drops).
• Do not use this valve on an evaporator with a distributor — in that case an externally equalized TE 2 is required.