The Belimo ZONE215S-35+ZONE24NO-S is a 1/2-inch two-way sweat zone valve assembly that pairs the ZONE215S-35 forged brass valve (Cv 3.5, 30 psi close-off) with the ZONE24NO-S AC 24 V spring return on/off actuator. It is normally open and includes one built-in SPST auxiliary switch.
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-35 (rev. 2023-01-10) and ZONE215S-35+ZONE24NO-S (valve and ZONE24NO-S 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-S actuator for 2-wire on/off control, normally open, AC 24 V.
Close-Off and Body Rating
30 psi close-off pressure with a 300 psi body pressure rating and Cv 3.5.
Built-In Auxiliary Switch
One SPST auxiliary switch rated 0.4 A resistive (0.4 A inductive) @ AC 24 V.
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-35 |
|---|---|
| Valve Size | 1/2 in. [DN 15] |
| Pipe Connection | Sweat |
| Flow Pattern | 2-way |
| Cv | 3.5 |
| Close-Off Pressure | 30 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-S |
|---|---|
| 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) |
| Auxiliary Switch | 1 x SPST, 0.4 A resistive (0.4 A inductive) @ AC 24 V |
| Lead Colors | Black (power), red (auxiliary switch) |
| 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-35+ZONE24NO-S?
The ZONE215S-35+ZONE24NO-S has a Cv of 3.5 and a close-off pressure of 30 psi. The valve body is rated for 300 psi.
Is the Belimo ZONE215S-35+ZONE24NO-S normally open or normally closed?
The ZONE215S-35+ZONE24NO-S is normally open. It uses the ZONE24NO-S fail-safe spring return actuator for 2-wire on/off control.
What power does the ZONE24NO-S actuator require?
The ZONE24NO-S runs on AC 24 V, 50/60 Hz. It draws 6.5 W in operation with 7 VA transformer sizing (class 2 power source).
Does the Belimo ZONE215S-35+ZONE24NO-S have an auxiliary switch?
Yes. The ZONE24NO-S has one built-in SPST auxiliary switch rated 0.4 A resistive (0.4 A inductive) @ AC 24 V.
What pipe connection does the Belimo ZONE215S-35+ZONE24NO-S use?
The ZONE215S-35+ZONE24NO-S has 1/2 in. [DN 15] sweat connections in a 2-way pattern.
What fluids and temperatures can the Belimo ZONE215S-35+ZONE24NO-S handle?
The ZONE215S-35+ZONE24NO-S 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-35+ZONE24NO-S?
The ZONE215S-35+ZONE24NO-S carries a 2-year Belimo warranty.
- Valve Pattern:
- 2-Way
- Valve Size:
- 1/2 Inch
- Connection Type:
- Sweat
- CV Rating:
- 3.5
- Max Close-Off Pressure:
- 30 psi
- Max Operating Pressure:
- 300 psi
- Medium Temperature Range:
- 32-212 °F
- Body Material:
- Forged Brass
- Actuator Type:
- Fail-Safe
- Fail-Safe Position:
- Fail Open
- Voltage:
- 24VAC
- Control Signal:
- On/Off
- Auxillary Switch:
- (1) SPST 0.4A @ 24VAC
- Power Connection:
- Wire Leads
