The Belimo Z2050Q-F is a 2-way, 1/2″ ZoneTight (QCV) ball zone valve body with female NPT connections and a Cv of 1.4, supplied without an actuator. It is rated 360 psi with 75 psi close-off, 0% leakage and an equal percentage flow characteristic, for chilled or hot water up to 60% glycol between 36 and 212°F. Belimo CQB(X) non fail-safe and CQKB(X) electronic fail-safe ZoneTight actuators snap onto the valve without tools.
Specifications on this page are taken from the Belimo Z2050Q-F technical data sheet, revision 2026-02-07, and the Belimo ZoneTight brochure (PF_37, 05/25). Verified 2026-09-09.
Replacing or stocking the valve body alone when an existing CQ or CQK ZoneTight actuator will be reused. Belimo lists unit ventilators, fan coil units, VAV reheat coils, fin tube casing, radiant panels and duct coils as common applications for the QCV zone valve in large commercial buildings.
Key Features
Zero Leakage Shutoff
Belimo publishes a 0% leakage rate and a 75 psi close-off pressure for the Z2050Q-F, with a 360 psi body rating.
Equal Percentage Flow Characteristic
Belimo publishes an equal percentage flow characteristic for the chrome-plated brass ball, with a 15...90° angle-of-rotation operating range and 75° controllable flow range.
Field-Adjustable Maximum Flow
An end-stop clip on the actuator changes the angle of rotation in 2.5° increments to set the maximum flow, from Cv 0.1 up to the full Cv 1.4, without tools.
Tool-Free Snap Assembly
The actuator plugs onto the valve by hand in vertical movements only; pins must match the holes on the flange. Mounting orientation can be selected in 180° increments.
Forged Brass, 360 psi Body
Forged brass body with brass stem, PTFE seat with EPDM O-ring and lubricated EPDM O-rings, rated 360 psi and 36...212°F [2...100°C] for chilled or hot water up to 60% glycol.
Compact Footprint
Belimo lists the QCV for space-restricted areas; the ZoneTight brochure gives an installation height of 4.33 inches (110 mm) for the valve and actuator assembly.
Technical Specifications
| Specification | Detail |
|---|---|
| Valve Type | ZoneTight (QCV) ball zone valve, 2-way |
| Valve Size | 1/2″ [DN 15] |
| Pipe Connection | Internal thread, NPT (female) |
| Cv | 1.4 |
| Flow Characteristic | Equal percentage |
| Leakage Rate | 0% |
| Fluid | Chilled or hot water, up to 60% glycol |
| Fluid Temperature Range (water) | 36...212°F [2...100°C] |
| Body Pressure Rating | 360 psi |
| Close-off Pressure Δps | 75 psi |
| Differential Pressure Δpmax | 40 psi |
| Angle of Rotation | Operating range 15...90° |
| Controllable Flow Range | 75° |
| Flow Direction | Direction of flow in both directions possible |
| Installation Orientation | Upright to horizontal (in relation to the spindle); not in a hanging position with the stem pointing downwards |
| Servicing | Maintenance-free |
| Valve Body | Forged brass |
| Stem | Brass |
| Stem Seal | EPDM O-ring |
| Seat | PTFE, O-ring EPDM |
| O-ring | EPDM (lubricated) |
| Ball | Chrome plated brass |
| Suitable Actuators | Non fail-safe CQB(X); electronic fail-safe CQKB(X) |
| Valve Weight | 0.31 lb [0.14 kg] (TDS rev 2026-02-07); 0.15 lb [0.070 kg] (2024-06-12 revision) — see note |
| Assembly Dimensions with CQK actuator | A 4.5″ [114] · B 2.0″ [52] · C 3.3″ [83] · D 2.7″ [69] · E 0.9″ [24] · F 0.9″ [24] |
| Assembly Dimensions with CQ actuator | A 4.5″ [114] · B 2.0″ [52] · C 3.1″ [80] · D 2.6″ [65] · E 1.0″ [25] · F 1.0″ [26] |
| Field Flow Setting (end-stop clip) | position 1 = Cv 0.1; position 3- = Cv 0.2; position 4+ = Cv 0.4; position 5+ = Cv 0.6; position 6 = Cv 0.8; position N = Cv 1.2; position No end stop = Cv 1.4 (V'nom) — IOM 71694-00001.K / 71775-00001.L |
| Manufacturer | Belimo |
| Manufacturer Part Number | Z2050Q-F |
| Warranty | 5 years |
Documentation
Belimo Z2050Q-F Technical Data Sheet (rev 2026-02-07)- CQ Actuator Quick Mount Instructions with ZoneTight Zone Valves (71694-00001.K)
- CQK Actuator Quick Mount Instructions with ZoneTight Zone Valves (71775-00001.L)
- Belimo ZoneTight Zone Valves Brochure
- Belimo ZoneTight Zone Valve Guide Specification (Section 230900)
Related Products
- Belimo Z2050Q-F+CQB24-3 — with non-spring return on/off / floating actuator, 24 VAC/DC
- Belimo Z2050Q-F+CQB24-SR-L — with non-spring return modulating actuator, 2 VDC = open
- Belimo Z2050Q-F+CQKB24-RR — with electronic fail-safe on/off actuator, fails closed
- Belimo Z2050Q-F+CQKB24-SR-LL — with electronic fail-safe modulating actuator, fails open
- Belimo Z2050Q-F+CQKBUP-LL — with electronic fail-safe on/off actuator, 100-240 VAC, fails open
Frequently Asked Questions
What is the Belimo Z2050Q-F?
The Z2050Q-F is Belimo's 2-way, 1/2″ NPT ZoneTight (QCV) ball zone valve body with a Cv of 1.4. This listing is the valve body only; the actuator is sold separately.
Which actuators fit the Belimo Z2050Q-F?
Belimo lists the CQB(X) non fail-safe and CQKB(X) electronic fail-safe ZoneTight actuators as suitable. They mount by tool-free snap assembly. Assembled versions are linked under Related Products.
What is the close-off and pressure rating of the Z2050Q-F?
Belimo publishes a close-off pressure of 75 psi, a maximum differential pressure of 40 psi and a body pressure rating of 360 psi.
Can the maximum flow of the Z2050Q-F be reduced in the field?
Yes. The actuator end-stop clip changes the angle of rotation in 2.5° increments to set the maximum flow. For the Z2050Q(S)-F the published end-stop positions are: position 1 = Cv 0.1; position 3- = Cv 0.2; position 4+ = Cv 0.4; position 5+ = Cv 0.6; position 6 = Cv 0.8; position N = Cv 1.2; position No end stop = Cv 1.4 (V'nom). After changing the clip on a modulating actuator, an adaptation must be triggered.
What fluids and temperatures is the Z2050Q-F rated for?
Chilled or hot water with up to 60% glycol, 36...212°F [2...100°C]. Belimo notes that if the temperature exceeds 212°F due to a boiler control failure the valve will safely contain the hot water, but the manufacturer's product warranty becomes invalid.
Can the Z2050Q-F be installed with the stem pointing down?
No. Belimo permits upright to horizontal orientation in relation to the spindle; the valve may not be installed in a hanging position with the stem pointing downwards. Flow is permitted in both directions.
Does the Z2050Q-F need a strainer?
Belimo states that its valves are regulating devices and must be kept free from particle debris such as welding beads, and recommends installing a suitable strainer.
- Valve Pattern:
- 2-Way
- Valve Size:
- 1/2 Inch
- Connection Type:
- NPT
- CV Rating:
- 1.4
- Actuator Type:
- Valve Only
