The Belimo B6500S-290+GKRX24-MFT is a 5 in. 2-way characterized control valve (CCV), Cv 290, with a stainless steel ball and stem, assembled with the Belimo GKRX24-MFT electronic fail-safe actuator for MFT programmable control on a 24 VAC/DC supply.
A stainless steel characterized disc gives the valve an equal percentage flow characteristic. Rated ANSI Class 125, standard class B body pressure and 175 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
Stainless steel disc produces an equal percentage flow characteristic.
Electronic Fail-Safe
GKRX24-MFT is an electronic fail-safe actuator: fail-safe direction reversible with switch; fail-safe running time <35 s.
MFT Programmable
Operating range Y 2...10 V; optional modes variable (VDC, on/off, floating point).
Pressure Ratings
ANSI Class 125, standard class B body pressure rating, 175 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 B6500S-290 | |
|---|---|
| Valve Size | 5" [125] |
| Fluid | chilled or hot water, up to 60% glycol |
| Fluid Temperature Range | 0...250°F [-18...120°C] |
| Close-Off Pressure (∆ps) | 175 psi |
| Flow Characteristic | equal percentage |
| Leakage Rate | 0% for A–AB |
| Pipe Connection | Flange for use with ASME/ANSI class 125 |
| Servicing | maintenance-free |
| Flow Pattern | 2-way |
| Controllable Flow Range | 75° |
| Valve Body | Cast iron - GG 25 |
| Stem | stainless steel |
| Stem Seal | EPDM (lubricated) |
| Seat | PTFE |
| Characterized Disc | Stainless steel |
| O-ring | EPDM (lubricated) |
| Ball | stainless steel |
| Cv | 290 |
| Body Pressure Rating | ANSI Class 125, standard class B |
| Flow Rate @ 4 psi Pressure Drop | 580 GPM |
| Valve Weight | 67 lb [31 kg] |
| Actuator: Belimo GKRX24-MFT | |
|---|---|
| Nominal voltage | AC/DC 24 V |
| Nominal voltage frequency | 50/60 Hz |
| Nominal voltage range | AC 19.2...28.8 V / DC 21.6...28.8 V |
| Power consumption in operation | 12 W |
| Power consumption in rest position | 3W |
| Transformer sizing | 21 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, 1500 Ω for PWM, On/Off and Floating point |
| Operating range Y variable | Start point 0.5...30 V End point 2.5...32 V |
| Operating modes optional | variable (VDC, on/off, floating point) |
| Position Feedback U | 2...10 V |
| Position feedback U note | Max. 0.5 mA |
| Position feedback U variable | VDC variable |
| Bridging time (PF) | 2s |
| Bridging time (PF) variable | 0...10 s |
| Pre-charging time | 5...26 s |
| Direction of motion motor | selectable with switch 0/1 |
| Direction of motion fail-safe | reversible with switch |
| Manual override | external push button |
| Angle of rotation | Max. 90° |
| Angle of rotation note | adjustable with mechanical stop |
| Running Time (Motor) | 150 s / 90° |
| Running time motor variable | 90...150 s |
| Running time fail-safe | <35 s |
| Sound power level motor | 52 dB(A) |
| Sound power level, fail-safe | 61 dB(A) |
| Position indication | Mechanical, 30...65 mm stroke |
| 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 | 5.4 lb [2.4 kg] |
Compatible Accessories
Belimo accessories for the B6500S-290+GKRX24-MFT, available from ZOT Supply.
Electrical Accessories
Gateways
Documentation
Belimo B6500S-290+GKRX24-MFT Technical Data Sheet (Valve + Actuator)belimo_LGCCV_installation-instructions_en-us.pdfCharacterized Control Valve (CCV) Technical DocumentationElectronic Valve Applications Guidebelimo_electronic-fail-safe-supercap_brochure_en-us.pdfZTH BrochureMP-Bus Technology: Notes for Project PlanningBelimo 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 B6500S-290+GKRX24-MFT?
The B6500S-290 valve is rated Cv 290. At a 4 psi pressure drop it passes 580 GPM of water.
What size and pipe connection does the B6500S-290+GKRX24-MFT use?
5 in. (5" [125]) with flange for use with ASME/ANSI class 125 connections.
Is the B6500S-290+GKRX24-MFT fail-safe?
Yes. The GKRX24-MFT is an electronic fail-safe actuator. Fail-safe running time: <35 s.
What control signal does the B6500S-290+GKRX24-MFT accept?
The GKRX24-MFT accepts MFT programmable control, operating range Y 2...10 V (4...20 mA w/ ZG-R01 (500 Ω, 1/4 W resistor)).
What power supply does the B6500S-290+GKRX24-MFT need?
Nominal voltage AC/DC 24 V. Transformer sizing: 21 VA.
What warranty does the B6500S-290+GKRX24-MFT 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 B6500S-290+GKRX24-MFT?
ZOT Supply carries these compatible Belimo accessories: P140A GR (Feedback potentiometer 140 Ω add-on, grey); P500A GR (Feedback potentiometer 500 Ω add-on, grey); P1000A GR (Feedback potentiometer 1 kΩ add-on, grey); P2800A GR (Feedback potentiometer 2.8 kΩ add-on, grey); P5000A GR (Feedback potentiometer 5 kΩ add-on, grey); P10000A GR (Feedback potentiometer 10 kΩ add-on, grey); S1A (Auxiliary switch 1x SPDT add-on); S2A (Auxiliary switch 2x SPDT add-on); ZTH US (Service tool, with ZIP-USB function, for programmable and communicative Belimo actuators, VAV controller and HVAC performance devices); UK24BAC (Gateway MP to BACnet MS/TP); UK24MOD (Gateway MP to Modbus RTU); UK24LON (Gateway MP to LonWorks).
What is the close-off pressure of the B6500S-290+GKRX24-MFT?
175 psi close-off pressure, with an ANSI Class 125, standard class B body pressure rating.
What fluids can the B6500S-290+GKRX24-MFT control?
Chilled or hot water, up to 60% glycol, fluid temperature range 0...250°F [-18...120°C].
Specifications per Belimo B6500S-290 technical data sheet (2026-11-06) and Belimo GKRX24-MFT technical data sheet (2026-08-18); flow rate 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:
- 5 Inch
- CV Rating:
- 290
- GPM:
- 580 @ 4 psi
- Material:
- Stainless Steel
- Actuator Type:
- Fail-Safe
- Voltage:
- 24VAC/DC
- Control Signal:
- MFT Programmable
- Auxillary Switch:
- None
- Enclosure:
- NEMA 2
