The Belimo B6800VB-865+PRXUP-MFT-T pairs the B6800VB-865 8" characterized control V-ball valve with a factory-mounted non-spring return valve actuator. It delivers a Cv of 865 (about 1730 GPM of water at a 4 psi drop, ASHRAE standard), 250 psi close-off, and ANSI Class 150 body strength with a ANSI flanged 8" connection. Equal-percentage flow and 300:1 rangeability give precise, repeatable modulating control across the full stroke.
Specifications per the Belimo B6800VB-865 product datasheet and the B6800VB-865+PRXUP-MFT-T assembly datasheet (en-us).
Overview
Belimo VB Series characterized control valves combine a contoured ball and insert to linearize flow and hold valve authority, giving stable hydronic control across the full stroke. The B6800VB-865 body is rated ANSI Class 150 with 250 psi close-off and a ANSI flanged 8" connection, and ships factory-assembled and tested with the PRXUP-MFT-T actuator as a matched, ready-to-wire unit.
Best for
- 8" 2-way chilled-water and hot-water control in air handlers, fan-coil banks, and central-plant hydronic loops
- Applications requiring tight 250 psi close-off and precise modulating control
- Equal-percentage flow with 300:1 rangeability for repeatable modulation
- Factory-assembled valve and actuator — no field coupling or mounting guesswork
Key Features
Characterized control
Equal-percentage ball and contoured insert linearize flow and hold valve authority for stable loop control.
Tight 250 psi close-off
Rated to 250 psi close-off (∆ps) with ANSI Class IV / equal-percentage seating to limit leak-by at shutoff.
Factory-assembled unit
Valve and actuator ship assembled and tested as a matched pair — no field coupling required.
Non fail-safe actuator
Non-Spring Return Valve Actuator, 24-240VAC/24-125VDC, Programmable (2-10VDC Default) Control, 2x SPDT, BACnet MS/TP, Modbus RTU, MP-Bus, Terminals.
300:1 rangeability
Wide controllable flow range supports precise low-flow modulation and accurate setpoint tracking.
Belimo reliability
Industrial-grade stainless ball and stem with proven Belimo actuator drive for long service life.
Technical Specifications
| Parameter | Specification |
|---|---|
| Manufacturer | Belimo |
| Assembly Part Number | B6800VB-865+PRXUP-MFT-T |
| Valve Model | B6800VB-865 |
| Actuator Model | PRXUP-MFT-T |
| Valve Size | 8" |
| Flow Pattern | 2-way |
| Cv (flow coefficient) | 865 |
| Nominal Flow (water) | 1730 GPM at 4 psi ∆P (ASHRAE) |
| Body Pressure Rating | ANSI Class 150 |
| Close-off Pressure ∆ps | 250 psi |
| Flow Characteristic | Equal percentage |
| Rangeability Sv | 300:1 |
| Leakage Rate | ANSI Class IV |
| End Connection | Flange (ANSI B16.1/B16.5) |
| Media | Chilled or hot water, up to 60% glycol, steam |
| Actuator Type | Non fail-safe |
| Power Supply | 24-240VAC / 24-125VDC |
| Control Signal | Modulating, MFT/Programmable, Communicative |
| Approx. Assembly Weight | 166.0 lb |
Documentation
Belimo B6800VB-865 Valve DatasheetBelimo B6800VB-865+PRXUP-MFT-T Assembly DatasheetBelimo VB Installation InstructionsRelated Products
Frequently Asked Questions
Does this valve come with the actuator attached?
Yes. The B6800VB-865+PRXUP-MFT-T ships as a factory-assembled, tested valve-and-actuator unit. The PRXUP-MFT-T actuator is mounted and ready to wire.
What media can this valve handle?
Chilled or hot water and water with up to 60% glycol, plus steam service within the rated temperature range.
What is the close-off pressure?
250 psi (∆ps) on water, giving dependable shutoff in commercial and industrial hydronic systems.
Is this a 2-way or 3-way valve?
This is a 2-way characterized control ball valve for modulating or two-position service depending on the actuator.
How many GPM will this valve flow?
With a Cv of 865, it passes about 1730 GPM of water at a 4 psi pressure drop, the ASHRAE standard sizing point (GPM = Cv x square root of ∆P). Flow scales with the square root of the pressure drop, so at 1 psi it is about 865 GPM and at 9 psi about 2595 GPM. Size to your actual design ∆P.
Does the actuator support BACnet or Modbus?
Yes. This actuator provides BACnet MS/TP, Modbus RTU, and MP-Bus communication alongside the analog 2-10 VDC default control signal.
- Pattern:
- 2-way
- Valve Size:
- 8 inch
- Cv:
- 865
- GPM:
- 1730
- End Fitting:
- Flange
- Actuator Type:
- Non fail-safe
- Voltage AC/DC:
- 24 V
- Control Type:
- Modulating
- Control Type:
- MFT/Programmable
- Control Type:
- Communicative