The Caleffi 508013A is a HYGROCAL air vent with a 1/8 in NPT male connection and a brass body, used to automatically discharge air that collects at the high points of hydronic heating and cooling systems.
Product data compiled from Caleffi North America technical documentation. Last reviewed June 2026.
Key Features
Automatic Air Discharge
A float mechanism opens to release accumulated air automatically, then reseals as the system fills.
High-Point Venting
Installs at manifolds, separators and pump locations where air naturally collects.
1/8 In Npt Male Connection
1/8 in NPT male connection sized for the application.
Brass Construction
Brass body with stainless and EPDM internal components for hydronic service.
Technical Data
| Function | Automatic float air vent |
|---|---|
| Series | Caleffi HYGROCAL |
| Connection | 1/8 in NPT male |
| Body material | Brass |
| Maximum operating pressure | 150 psi |
| Medium temperature range | 40 - 212 °F |
| Finish | Chrome |
Documentation
Technical brochureRelated Products
Frequently Asked Questions
At the high points of a hydronic system such as manifolds, air separators and pump locations, where air naturally collects.
An internal float drops as air accumulates, opening the discharge port; when water returns, the float rises and reseals the vent.
150 psi maximum operating pressure with a medium temperature range of 40 - 212 °F.
- Type:
- Air Vent
- Series:
- HYGROCAL
- Body Material:
- Brass
- Connection Type:
- NPT Threaded
- Connection Size:
- 1/8 in
