The Caleffi 304759A is a 3047 Check Valve inline check valve with 3/4" Press/Sweat connections. It uses low-lead brass suitable for potable water service.
Best for reverse-flow prevention where silent closure matters, such as pump discharge and multi-boiler headers.
Specifications sourced from Caleffi North America technical literature. Last reviewed July 2026.
Key Features
Serviceable Cartridge Design
The internal check cartridge is removable, so the seat and spring can be inspected or replaced without cutting the valve out of the line.
Silent Spring-Loaded Closure
A spring returns the disc to its seat before flow reverses, preventing the water hammer that a swing check can produce on pump shutdown.
Low-Lead Brass Construction
Wetted surfaces carry a weighted average lead content below 0.25%, meeting Section 1417 of the Safe Drinking Water Act for potable water service.
Technical Specifications
| Product Type | Inline Check Valve |
| Connection Size | 3/4" |
| Connection Type | Press/Sweat |
| Series | 3047 Check Valve |
| Maximum operating pressure | 150 psi |
| Medium temperature range | 32 - 250 deg F |
| Material | DZR low lead brass |
| Lead Content | Low-lead brass, below 0.25% weighted average |
| Shipping Weight | 0.65 lb |
Documentation
Related Products
- Caleffi 304750A : 3047 Check Valve 3/4" Male NPT
- Caleffi 304753A : 3047 Check Valve 3/4" Female NPT
- Caleffi 304756A : 3047 Check Valve 3/4" Press
- Caleffi 304757A : 3047 Check Valve 3/4" PEX Crimp
Frequently Asked Questions
What does Caleffi 304759A do?
It is a spring-loaded inline check valve. It permits flow in one direction and closes before reverse flow develops, preventing reverse flow and the water hammer a swing check can cause on pump shutdown.
Is Caleffi 304759A serviceable in place?
Yes. The check cartridge is removable, so the seat and spring can be inspected or replaced without cutting the valve body out of the line.
What connection does Caleffi 304759A use?
It is supplied with 3/4" Press/Sweat connections. Other sizes and connection styles in the 3047 Check Valve range are listed under Related Products.
What are the pressure and temperature limits of Caleffi 304759A?
Maximum operating pressure is 150 psi.
Is Caleffi 304759A approved for potable water?
It uses low-lead brass with a weighted average lead content below 0.25% of wetted surfaces, meeting Section 1417 of the Safe Drinking Water Act. Confirm acceptance with the authority having jurisdiction for the specific application.
- Product Type:
- Inline Check Valve
- Series:
- 3047 Check Valve
- Product Family:
- Check Valves
- Connection Type:
- Press/Sweat
- Connection Size:
- 3/4 inch
- Lead Content:
- Low-Lead Brass
- Max Operating Pressure:
- 150 psi