Product Overview

Operating principle
The accumulation of air bubbles in
the valve body causes the float to
drop so that the obturator opens.
This action, and therefore correct
valve operation, is ensured as
long as the water pressure
remains under the maximum
discharge pressure.
Installation
DISCALAIR series 251
automatic air vent valves
must be installed
vertically, typically on the
top of solar heating system panels and at points in the circuit where
bubbles of air that must be discharged gather.
They must always be installed in combination with a shut-off valve.
This is necessary since the vent valves must be shut off after use, to
remove the air in the phase of filling and starting up the system.
Hydraulic characteristics
Discharge capacity in the phase of filling the system
Construction details
Resistance to heat and high discharge pressure
The high performance of this series of automatic air vent valves,
moreover required in solar heating systems, is ensured by the use
of particularly heat resistant materials.
They allow maintaining the functional features of the valve with
glycol water temperatures up to 160°C. The internal geometry of
the valve has been designed to be able to discharge the air up to
a pressure of 10 bar.
Application diagram
T
Tmax= 160
°
C / 320
°
F
P max = 10 bar / 150 psi
Nl/s
0
0
bar (air)
0,1
12
3456
0,5 1,5 2,5
3,5 4,5 5,5
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
7
6,5
1,5
1,1
1,2
1,3
1,4
8
7,5
9
8,5
10
9,5
T max = 160°C / 320°F
P max = 10 bar / 150 psi
T
max
= 160°C / 320°F
P
max
= 10 bar / 150 psi
T max = 160°C / 320°F
P max = 10 bar / 150 psi
T
max
= 160°C / 320°F
P
max
= 10 bar / 150 psi
Maintenance
The DISCALAIR automatic air vent valve is
built to permit inspecting the internal
mechanism.
Access to the moving parts that govern the air
vent is attained by simply taking off the top
cover. The body moreover can be separated
from the bottom portion connected to the pipe.
A shut-off valve must be installed before the
DISCALAIR device in order to simplify any
maintenance work and for shutting off after the
phase of filling.
T max = 160°C / 320°F
P max = 10 bar / 150 psi
DISCAL AAIIRR SOLAR 251 series
High-performance automatic air vent valve for solar heating systems. Connections 1/2” F. Brass body, chrome plated. High
resistance polymer float. Stainless steel float lever and spring. Brass float guide. Dezincification resistant alloy obturator stem. High
resistance elastomer hydraulic seals. Medium water and glycol solutions; maximum percentage of glycol 50%. Temperature range
-30–160°C. Maximum working pressure 10 bar. Maximum discharge pressure 10 bar.
SPECIFICATION SUMMARIES
We reserve the right to change our products and their relevant technical data, contained in this publication, at any time and without prior notice.
CALEFFI S.P.A. · I · 28010 FONTANETO D’AGOGNA (NO) · S.R. 229, N.25 · TEL.INT. [phone] R.A. · FAX [phone]
· Http://www.caleffi.com · E-mail: [e-mail] ·
CALEFFI