
Specifications
Description
The Watts 530C-100-300 is a 1/2" calibrated adjustable pressure relief valve for thermal expansion / general service service, field-adjustable over 100-300 psi. It features a brass body. Rated to 300 psi and up to 180°F.
This 3/4 inch calibrated pressure relief valve is used in commercial, residential and industrial applications to protect against excessive pressure in systems containing water, oil, or air. It consists of a bronze body construction with 3/4 inch NPT threaded male inlet and 1/2 inch NPT threaded female (drain) outlet connections, stainless steel spring, brass bonnet, Buna-N disc, and Buna-N O-ring. It has a calibrated adjustment feature for setting the valve to the required relief pressure, and is ideal for by-pass thermal expansion pressure relief (not ASME approved). It is for use in fire protection systems. The maximum pressure is 300 psi (20.67 bar). The adjustable pressure range is 100 to 300 psi (3.45 to 12.06 bar).
Features
- Bronze body construction
- All stainless steel spring
- Designed for protection against excessive pressure build up
- model also available for fire protection systems
Common Questions
- What pressure does this relieve at?
- This is a calibrated valve — you set it. It adjusts over 100-300 psi, so it has no factory set point. Set it below the working pressure rating of the equipment you are protecting, and re-check the setting after installation.
- Is this ASME rated?
- No. This is a calibrated relief valve and is explicitly not ASME approved, so it may not be used as the code-required safety relief on a boiler or a water heater. It is intended for thermal expansion and general bypass duty. Where an ASME valve is required, specify one that carries the HV stamp.
- Can I use this on potable water?
- No. This model is not certified lead-free, so it cannot be installed in a potable (drinking) water line under the NSF/ANSI 372 weighted-average lead rule. Use it on non-potable service, or order the "LF" version of this model for potable water.
Specifications
- Type: Relief
- Size: 1/2"
- Inlet Size: 3/4"
- Outlet Size: 1/2"
- Connection: NPT
- Body Material: Brass
- Max Pressure (psi): 300
- Pack Quantity: 50
- Country of Origin: United States
- Warranty: 1 Year Limited
- MPN: 530C-100-300
- Temperature: up to 180°F
- Lead-Free: No
- Relief Type: Calibrated Adjustable
- Adjustment Range: 100-300 psi
- ASME Code Rating: Not ASME Rated
- Application: Thermal Expansion / General Service
- Connection Configuration: MNPT inlet x FNPT outlet
- Approved for Potable Water: No
- SentryPlus Alert Flood Sensor: No
Product Information
Dimensions
| Size Nominal | 1/2" | Inlet Size | 3/4" |
| Outlet Size | 1/2" | End Connection | NPT |
Details
| Series | 530C | Device Type | Relief |
| Body Material | Brass | Max Pressure PSI | 300.0 psi |
| Max Temp °F | 180.0 °F | Pack Qty | 50 |
| Relief Type | Calibrated Adjustable | Adjustable Range PSI | 100-300 psi PSI |
| ASME Rating | Not ASME Rated | Application Class | Thermal Expansion / General Service |
| Connection Config | MNPT inlet x FNPT outlet | — | — |
Compare with similar products
| Relief Type | Calibrated Adjustable
| Calibrated Adjustable
| Calibrated Adjustable
|
| Adjustable Range PSI | 100-300 psi
| 10-50 psi
| 45-100 psi
|
| Application Class | Thermal Expansion / General Service
| Pump Bypass Pressure Control
| Pump Bypass Pressure Control
|
| Connection Config | MNPT inlet x FNPT outlet
| MNPT inlet x FNPT outlet
| MNPT inlet x FNPT outlet
|
| Potable Approved | — | Yes | Yes |
| Series | 530C
| LFBP30
| LFBP30
|
| Country Of Origin | United States
| United States
| United States
|
| Warranty | 1 Year Limited
| 1 Year Limited
| 1 Year Limited
|
| Spec Sheet | |||
| Device Type | Relief
| Relief
| Relief
|
| Size Nominal | 1/2"
| 1/2"
| 1/2"
|
| Inlet Size | 3/4"
| 1/2"
| 1/2"
|
| Outlet Size | 1/2"
| 1/2"
| 1/2"
|
| Lead Free | — | Yes | Yes |
| End Connection | NPT
| NPT
| NPT
|
| Body Material | Brass
| Copper
| Copper
|
| Max Pressure PSI | 300.0 psi | 50.0 psi | 100.0 psi |
| Max Temp °F | 180.0 °F | 180.0 °F | 180.0 °F |
| Pack Qty | 50
| 12
| 12
|
| Options | — | Bypass
| Bypass
|
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