The Caleffi NA502640A is a PLUMBVENT automatic air vent with 1/2" NPT connections. It uses low-lead brass suitable for potable water service.
Best for plumbing risers and potable water systems where a weeping vent would cause water damage.
Specifications sourced from Caleffi North America technical literature. Last reviewed July 2026.
Key Features
Hygroscopic Safety Cap
A moisture-sensitive cap swells and seals if the vent begins to weep, containing the leak until the vent can be serviced.
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 | Automatic Air Vent |
| Connection Size | 1/2" |
| Connection Type | NPT |
| Series | PLUMBVENT |
| Maximum operating pressure | 150 psi |
| Maximum air discharge pressure | 90 psi |
| Maximum working temperature | 240 deg F |
| Maximum discharge rate | 1.75 SCFM |
| Lead Content | Low-lead brass, below 0.25% weighted average |
| Shipping Weight | 0.6 lb |
Documentation
Frequently Asked Questions
What is the hygroscopic cap on Caleffi NA502640A for?
The cap contains a moisture-sensitive element that swells and seals if the vent starts to weep, containing the leak until the vent can be serviced. It is a safeguard against water damage from a failed vent.
What connection does Caleffi NA502640A use?
It is supplied with 1/2" NPT connections. Other sizes and connection styles in the PLUMBVENT range are listed under Related Products.
What are the pressure and temperature limits of Caleffi NA502640A?
Maximum operating pressure is 150 psi with a maximum working temperature of 240 deg F.
Is Caleffi NA502640A 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.
What is the warranty on Caleffi NA502640A?
Caleffi covers this product under its standard two-year limited warranty against defects in material and workmanship from the date of shipment. ZOT Supply is an authorized Caleffi distributor.
- Product Type:
- Automatic Air Vent
- Series:
- PLUMBVENT
- Product Family:
- Air Vents (plumbing)
- Connection Type:
- NPT
- Connection Size:
- 1/2 inch
- Lead Content:
- Low-Lead Brass
- Max Operating Pressure:
- 150 psi
- Max Working Temperature:
- 240 deg F