The Belimo ZONE215S-25+ZONE24NO is a 1/2-inch two-way sweat zone valve assembly that pairs the ZONE215S-25 forged brass valve (Cv 2.5, 50 psi close-off) with the ZONE24NO AC 24 V spring return on/off actuator. It is normally open.
Forged brass body, stainless steel stem and EPDM seat, with a 300 psi body pressure rating and ANSI Class III 0.1% leakage, for chilled or hot water up to 50% glycol.
Specifications verified October 2026 against Belimo technical data sheets ZONE215S-25 (rev. 2023-01-10) and ZONE215S-25+ZONE24NO (valve and ZONE24NO pages rev. 2022-01-12).
Best For
- Fan coil units and baseboards
- Hydronic zones that need fail-safe operation on 2-wire control
- Variable flow or constant flow hydronic systems
- Compact installations with limited space
- Chilled or hot water service with up to 50% glycol
Warranty
Both the valve and the actuator carry a 2-year Belimo warranty.
Key Features
Fail-Safe Spring Return
Spring return ZONE24NO actuator for 2-wire on/off control, normally open, AC 24 V.
Close-Off and Body Rating
50 psi close-off pressure with a 300 psi body pressure rating and Cv 2.5.
Brass Body, EPDM Seat
Forged brass valve body, stainless steel stem, EPDM seat and housing seal.
Listed and Certified
cULus listed and CE marked actuator, manufactured under ISO 9001.
Pre-Wired Leads
18 in. wire leads, 6.5 W in operation, 7 VA transformer sizing.
ZOT Supply is an authorized distributor of Belimo products.
Technical Specifications
| Valve Model | ZONE215S-25 |
|---|---|
| Valve Size | 1/2 in. [DN 15] |
| Pipe Connection | Sweat |
| Flow Pattern | 2-way |
| Cv | 2.5 |
| Close-Off Pressure | 50 psi |
| Body Pressure Rating | 300 psi |
| Flow Characteristic | On/off |
| Leakage Rate | ANSI Class III 0.1% |
| Fluid | Chilled or hot water, up to 50% glycol |
| Fluid Temperature Range | 32...212°F [0...100°C] |
| Valve Body | Forged brass |
| Housing Seal | EPDM |
| Stem | Stainless steel |
| Seat | EPDM |
| Suitable Actuators | Belimo ZONE spring return actuators |
| Valve Weight | 0.88 lb [0.40 kg] |
| Actuator Model | ZONE24NO |
|---|---|
| Actuator Type | Spring return, fail-safe |
| Normal Position | Normally Open |
| Control | On/off, 2-wire |
| Nominal Voltage | AC 24 V |
| Nominal Voltage Frequency | 50/60 Hz |
| Power Consumption in Operation | 6.5 W |
| Transformer Sizing | 7 VA (class 2 power source) |
| Lead Colors | Black (power) |
| Electrical Connection | 18 in. wire leads |
| Angle of Rotation | 90° |
| Noise Level, Motor | 35 dB(A) |
| Noise Level, Fail-Safe | 35 dB(A) |
| Degree of Protection IEC/EN | IP20 |
| Degree of Protection NEMA/UL | NEMA 1 |
| Enclosure | UL Enclosure Type 1 |
| Agency Listing | CE, cULus |
| Quality Standard | ISO 9001 |
| Ambient Temperature | 32...104°F [0...40°C] |
| Storage Temperature | -40...176°F [-40...80°C] |
| Ambient Humidity | Max. 95% RH, non-condensing |
| Servicing | Maintenance-free |
| Housing Material | Galvanized steel |
| A (actuator width) | 4.0 in. [102 mm] |
|---|---|
| B (valve end to end) | 2.8 in. [70 mm] |
| C (pipe centerline to top) | 3.5 in. [89 mm] |
| D (overall height) | 4.3 in. [110 mm] |
| E / F (centerline to side) | 1.2 in. [30 mm] / 1.2 in. [31 mm] |
Documentation
Frequently Asked Questions
What is the Cv and close-off pressure of the Belimo ZONE215S-25+ZONE24NO?
The ZONE215S-25+ZONE24NO has a Cv of 2.5 and a close-off pressure of 50 psi. The valve body is rated for 300 psi.
Is the Belimo ZONE215S-25+ZONE24NO normally open or normally closed?
The ZONE215S-25+ZONE24NO is normally open. It uses the ZONE24NO fail-safe spring return actuator for 2-wire on/off control.
What power does the ZONE24NO actuator require?
The ZONE24NO runs on AC 24 V, 50/60 Hz. It draws 6.5 W in operation with 7 VA transformer sizing (class 2 power source).
What pipe connection does the Belimo ZONE215S-25+ZONE24NO use?
The ZONE215S-25+ZONE24NO has 1/2 in. [DN 15] sweat connections in a 2-way pattern.
What fluids and temperatures can the Belimo ZONE215S-25+ZONE24NO handle?
The ZONE215S-25+ZONE24NO handles chilled or hot water with up to 50% glycol at fluid temperatures from 32 to 212°F [0 to 100°C].
What warranty comes with the Belimo ZONE215S-25+ZONE24NO?
The ZONE215S-25+ZONE24NO carries a 2-year Belimo warranty.
- Valve Pattern:
- 2-Way
- Valve Size:
- 1/2 Inch
- Connection Type:
- Sweat
- CV Rating:
- 2.5
- Actuator Type:
- Fail-Safe
- Voltage:
- 24VAC
- Control Signal:
- On/Off
- Auxillary Switch:
- None
