CALEFFI NA502740A Installation

Compact automatic air vent with check valve
©
Copyright 2020 Caleffi
Installation
The vent is installed in the vertical position in parts of the system where a concentration of air
pockets is to be expected.
Operating instructions
The automatic air vent can be used for manual or automatic venting of hydronic systems. The
automatic air vent is supplied complete with a safety hygroscopic cap that automatically closes
the air discharge in case of contact with water.
For normal automatic venting, keep hygroscopic cap closed for a slow release of air. A fast release
of the air may allow dirt or scale in the water to plug the operating mechanism. The small hole in
the side of the cap allows air to escape.
Service instructions
For optimum performance replace hygroscopic cap every 3 years. The natural cellulose fiber
washers can deteriorate over time when exposed to unfiltered or hard water.
Function
Float type automatic air vent designed to vent air that is released
from the water while being heated. Check valve allows for easy
replacement and cleaning without shutting down the system. This
air vent is equipped with a factory-installed hygroscopic safety cap
to automatically close air discharge in case of contact with water.
These items are designed for use in closed hydronic systems. Do
not use in plumbing applications. These items do not meet the low-
lead plumbing standards of U.S. and Canada.
Product range
Code NA502740A
valve and hygroscopic safety cap, ½" NPT male
Technical characteristics
Materials:
Body:
Seals:
Performance: Max. working pressure:
Max. discharge pressure:
Max. discharge flow rate:
Max. working temperature:
1
www.caleffi.com
NA502740A
automatic air vent with service check
peroxide-cured EPDM
150 psi (10 bar)
1.75 scfm (0.83 l/s)
NA10613.01
brass
90 psi (6 bar)
230°F (110°C)