The Caleffi 502243A is a VALCAL air vent with 1/2" NPT Threaded connections. Installed at system high points, its float-operated valve automatically releases air that accumulates in heating and air-conditioning circuits.
Best for automatic air release at system high points.
Specifications sourced from Caleffi North America technical literature. Last reviewed July 2026.
Key Features
Float-Operated Venting
As air collects in the vent body the internal float drops, opening the release valve; the valve closes automatically as the fluid level recovers.
System Protection
Continuous automatic air release helps reduce oxygen-driven corrosion, trapped-air noise in emitters and cavitation at circulator pumps.
Technical Specifications
| Function | Automatic float air vent |
| Series | Caleffi VALCAL |
| Connection | 1/2 in NPT male |
| Body material | Brass |
| Maximum operating pressure | 150 psi |
| Maximum air discharge pressure | 60 psi |
| Maximum discharge rate | 2.5 SCFM |
| Medium temperature range | 32 - 250 °F |
| Shipping Weight | 0.8 lb |
Documentation
Design Resources
Related Products
- Caleffi 502420 : ROBOCAL Air Vent 1/4" Metric Thread
- Caleffi 502630 : ROBOCAL Air Vent 3/8" Metric Thread
- Caleffi 502640 : ROBOCAL Air Vent 1/2" Metric Thread
- Caleffi 337221A : Manual Air Vent 1/4" NPT Threaded
Frequently Asked Questions
What does Caleffi 502243A do?
Caleffi 502243A is an air vent in the Caleffi VALCAL range. It automatically releases air that accumulates in the system, helping prevent oxygen-driven corrosion, trapped-air noise and pump cavitation.
What connection does Caleffi 502243A use?
It is supplied with 1/2" NPT Threaded connections. Other sizes and connection styles in the VALCAL range are listed under Related Products.
What are the pressure and temperature limits of Caleffi 502243A?
Maximum operating pressure is 150 psi, over a medium temperature range of 32 - 250 °F.
What is the warranty on Caleffi 502243A?
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:
- Air Vent
- Series:
- VALCAL
- Connection Type:
- NPT Threaded
- Connection Size:
- 1/2 in
- Max Operating Pressure:
- 150 psi
- Medium Temperature Range:
- 32 - 250 deg F
- Body Material:
- Brass
