The Belimo B231+ARX120-SR is a 1-1/4 in. 2-way characterized control valve (CCV), Cv 25, with a stainless steel ball and stem, assembled with the Belimo ARX120-SR non fail-safe actuator for modulating 2...10 V control on a 100-240 VAC supply.
A TEFZEL® characterized disc gives the valve an equal percentage flow characteristic. Rated 400 psi body pressure and 200 psi close-off, for chilled or hot water, up to 60% glycol from 0...250°F [-18...120°C].
Best For
- Heating and cooling coils in air handling units
- Fan coil unit heating and cooling coils
- Unit ventilators
- VAV box reheat coils
- Bypass loops
- Hydronic systems with variable flow
Warranty
This Belimo characterized control valve product carries a 5-year warranty on all components from the date of production, with the first two years unconditional.
Key Features
Characterized Disc
TEFZEL® disc produces an equal percentage flow characteristic.
Modulating Control
Proportional control on 2...10 V (4...20 mA w/ ZG-R01 (500 Ω, 1/4 W resistor)), with 2...10 V position feedback.
Pressure Ratings
400 psi body pressure rating, 200 psi close-off pressure.
Ball and Stem
Stainless steel ball, stainless steel stem, PTFE seat.
Plenum Rated
UL 2043: Suitable for use in air plenums per Section 300.22(C) of the NEC and Section 602 of the IMC.
ZOT Supply is an authorized distributor of Belimo products.
Technical Specifications
| Valve: Belimo B231 | |
|---|---|
| Valve Size | 1.25" [32] |
| Fluid | chilled or hot water, up to 60% glycol |
| Fluid Temperature Range | 0...250°F [-18...120°C] |
| Close-Off Pressure (∆ps) | 200 psi |
| Flow Characteristic | equal percentage |
| Leakage Rate | 0% for A–AB |
| Pipe Connection | Internal thread NPT (female) |
| Servicing | maintenance-free |
| Flow Pattern | 2-way |
| Controllable Flow Range | 75° |
| Valve Body | Nickel-plated brass body |
| Stem | stainless steel |
| Stem Seal | EPDM (lubricated) |
| Seat | PTFE |
| Characterized Disc | TEFZEL® |
| O-ring | EPDM (lubricated) |
| Ball | stainless steel |
| Cv | 25 |
| Body Pressure Rating | 400 psi |
| Flow Rate @ 4 psi Pressure Drop | 50 GPM |
| Valve Weight | 1.6 lb [0.73 kg] |
| Actuator: Belimo ARX120-SR | |
|---|---|
| Nominal voltage | AC 100...240 V |
| Nominal voltage frequency | 50/60 Hz |
| Nominal voltage range | AC 85...265 V |
| Power consumption in operation | 4W |
| Power consumption in rest position | 1W |
| Transformer sizing | 7.5 VA |
| Overload Protection | electronic thoughout 0...90° rotation |
| Operating Range Y | 2...10 V |
| Operating range Y note | 4...20 mA w/ ZG-R01 (500 Ω, 1/4 W resistor) |
| Input impedance | 100 kΩ for 2...10 V (0.1 mA), 500 Ω for 4...20 mA |
| Position Feedback U | 2...10 V |
| Position feedback U note | Max. 1 mA |
| Direction of motion motor | selectable with switch 0/1 |
| Manual override | external push button |
| Angle of rotation | 90° |
| Angle of rotation note | adjustable with mechanical stop |
| Running Time (Motor) | 90 s / 90° |
| Running time motor variable | 90 or 150 s |
| Sound power level motor | 45 dB(A) |
| Position indication | Mechanical, pluggable |
| Power Source (UL) | Class 2 Supply |
| Degree of Protection (NEMA/UL) | NEMA 2 |
| Housing | UL Enclosure Type 2 |
| Agency Listing | cULus acc. to UL60730-1A/-2-14, CAN/CSA E60730-1:02 CE acc. to 2014/30/EU and 2014/35/EU |
| Quality Standard | ISO 9001 |
| UL 2043 Compliant | Suitable for use in air plenums per Section 300.22(C) of the NEC and Section 602 of the IMC |
| Ambient humidity | Max. 95% RH, non-condensing |
| Ambient temperature | -22...122°F [-30...50°C] |
| Storage temperature | -40...176°F [-40...80°C] |
| Servicing | maintenance-free |
| Housing material | Galvanized steel and plastic housing |
| Actuator Weight | 2.3 lb [1 kg] |
Compatible Accessories
Belimo accessories for the B231+ARX120-SR, available from ZOT Supply.
Valve Accessories
Documentation
Belimo B231+ARX120-SR Technical Data Sheet (Valve + Actuator)CCV 4-Pin Removal Installation InstructionsCCV Installation InstructionsCharacterized Control Valve (CCV) Technical DocumentationCCV Accessories DocumentationElectronic Valve Applications GuideBelimo Ball Valve Master FormatSuccess Story: Habitat for Humanity Home with Belimo CCVSuccess Story: New York PostSuccess Story: Sonoma State University RenovationSuccess Story: Western Wyoming Community CollegeFrequently Asked Questions
What is the Cv of the Belimo B231+ARX120-SR?
The B231 valve is rated Cv 25. At a 4 psi pressure drop it passes 50 GPM of water.
What size and pipe connection does the B231+ARX120-SR use?
1-1/4 in. (1.25" [32]) with internal thread NPT (female) connections.
Is the B231+ARX120-SR fail-safe?
No. The ARX120-SR is a non fail-safe actuator.
What control signal does the B231+ARX120-SR accept?
The ARX120-SR accepts modulating 2...10 V control, operating range Y 2...10 V (4...20 mA w/ ZG-R01 (500 Ω, 1/4 W resistor)).
What power supply does the B231+ARX120-SR need?
Nominal voltage AC 100...240 V. Transformer sizing: 7.5 VA.
What warranty does the B231+ARX120-SR have?
A Belimo 5-year warranty on all components from the date of production, with the first two years unconditional.
What accessories are available for the B231+ARX120-SR?
ZOT Supply carries these compatible Belimo accessories: ZS-CCV-100 (Weather shield for characterized control valves, fits LRB(X) and ARB(X) actuators).
What is the close-off pressure of the B231+ARX120-SR?
200 psi close-off pressure, with a 400 psi body pressure rating.
What fluids can the B231+ARX120-SR control?
Chilled or hot water, up to 60% glycol, fluid temperature range 0...250°F [-18...120°C].
Specifications per Belimo B231 technical data sheet (2026-06-24) and Belimo ARX120-SR technical data sheet (2026-08-18); flow rate per Belimo CCV Technical Documentation (P10419 - 09/13); weather shield fit per Belimo CCV Technical Documentation (P10419 - 09/13); warranty per Belimo CCV Master Format, Section 230923.11. Content updated November 2026.
- Valve Pattern:
- 2-Way
- Valve Size:
- 1-1/4 Inch
- CV Rating:
- 25
- GPM:
- 50 @ 4 psi
- Material:
- Stainless Steel
- Actuator Type:
- Non Fail-Safe
- Voltage:
- 100-240VAC
- Control Signal:
- 2-10VDC
- Auxillary Switch:
- None
- Enclosure:
- NEMA 2
