Sanhua RFKH03-4.8-09A Thermostatic Expansion Valve – R404A/R507A, Internally Equalized, 1/2" Solder Outlet, 4.8 USRT

Sanhua RFKH03-4.8-09A, R404A/R507A refrigerant-specific thermostatic expansion valve (TXV). It continuously adjusts the refrigerant flow entering the evaporator according to the superheat at the evaporator outlet.

Internally Equalized Body (No Equalizer Port): For Evaporators with Low Pressure Drop

This model is internally equalized: there is no separate equalizer connection on its body; the valve references the pressure at the evaporator inlet. It works correctly on single-pass evaporators with low pressure drop; installation is also simple because there are fewer connections.

⚠️ When is internal equalization NOT ENOUGH? If the evaporator has a distributor, is multi-pass, or is a long/high pressure drop circuit, an internally equalized valve opens less than required and superheat control goes off. In these cases, the externally equalized (E) version should be selected — it is available in our catalog.

Technical Specifications (Official Sanhua Datasheet R2511)

• Model: Sanhua RFKH03-4.8-09A | Sanhua part no: 10201028702
• Refrigerant: R404A/R507A
• Rated Capacity: 4.8 USRT (≈ 16.9 kW)
• Equalization Type: Internal equalization (no equalizer connection)
• Connections: flare / solder — inlet 3/8" flare (threaded) · outlet 1/2" solder
• Evaporating Temperature Range: −40 … +10 °C (Range N)
• MOP: None — this variant is produced without the MOP function (Tab. A)
• Max. Working Pressure (PS): 4.6 MPa (46 bar)
• Ambient Temperature: −35 … +55 °C | Fluid Temperature: −40 … +70 °C
• Capillary Tube: 1.5 m, stainless steel capillary and sensing bulb
• Thermal Charge: Cross charge — stable superheat across the entire evaporating range
• ⚠️ Orifice NOT INCLUDED. Datasheet scope of delivery: valve body + bulb clamp. The orifice determines the capacity and must be ordered separately (0X ~ 6, available on our site). Orifice capacities for R404A/R507A (kW): 0X 0.7 · 0 1.4 · 1 2.8 · 2 4.0 · 3 6.8 · 4 10.8 · 5 14.1 · 6 16.8 — full table in the 2nd image
• Certificates: UL/CSA · PED declaration

• 🔧 Reading the code: RFKH = thermostatic expansion valve · 03 = R404A/R507A · NO letter E = internal equalization · 4.8 = rated capacity (USRT) · last digits variant/connection.
• ℹ️ The "A" suffix indicates the new generation. Sanhua has updated the RFKH series; in the current catalog all codes are published with the A suffix.
• 🔧 Attach the sensing bulb correctly: it is clamped to the suction line, on a horizontal section, at the 3 or 4 o'clock position with full contact with the pipe, and insulation is wrapped over it. If attached under the pipe (6 o'clock), oil accumulation causes false readings.
• Cool the valve body with a wet cloth while brazing and purge with nitrogen; excessive heat damages the internal seal and orifice.
• ⚠️ Refrigerant compatibility: This valve is charged for R404A/R507A; it must not be used in a system with another refrigerant — the thermal charge is different and superheat control goes off.