The Caleffi 304780A is a 3047 Check Valve inline check valve with 1-1/2" Male NPT connections. It uses low-lead brass suitable for potable water service.
Best for preventing backflow or backsiphonage in residential and commercial plumbing or hydronic systems.
Specifications sourced from Caleffi technical brochure 01426/25 NA and submittal data 03507 NA. Verified 5 August 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 | 1-1/2" |
| Connection Type | Male NPT |
| 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 | 5.4 lb |
Documentation
Related Products
- Caleffi 304786A : 3047 Check Valve 1-1/2" Press
- Caleffi 304789A : 3047 Check Valve 1-1/2" Sweat
- Caleffi 304740A : 3047 Check Valve 1/2" Male NPT
- Caleffi 304743A : 3047 Check Valve 1/2" Female NPT
Frequently Asked Questions
What does Caleffi 304780A 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 304780A 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 304780A use?
It is supplied with 1-1/2" Male NPT 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 304780A?
Maximum operating pressure is 150 psi.
Is Caleffi 304780A 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:
- Male NPT
- Connection Size:
- 1-1/2 inch
- Lead Content:
- Low-Lead Brass
- Max Operating Pressure:
- 150 psi
