AAF HermanNelson IM 725 Installation Manual - page 17
IM 725 (1-02)
17
Valves and Piping
The optional factory-supplied AAF
®
-HermanNelson
®
Control Valve(s)
for water applications can be either 2-way or 3-way type, and is / are
shipped separate from the unit ventilator itself so no shipping damage
occurs to the piping of the connection stub from the weight of the valve
and to provide the installer with maximum flexibility in making the
field piping connection. Before proceeding, see figures 53 through 62
as applicable, as well as the job-specific piping drawings.
Face and Bypass
2-Way and 3-Way End-of-Cycle Valves
Control
2 Position
Electrical
24 VAC, 50/60 Hz
Stroke
Power Stroke 9 to 11 seconds
Spring return 4 to 5 seconds
Ambient
32°F to 125°F (0°C to 52°C)
Connections
3
⁄
4
" FNPT
Static Pressure
300 psi (2100 kPa)
Close-Off Pressure
13 psi (90 kPa)
Temperature
32°F to 200°F (0°C to 93°C)
Connections
3
⁄
4
" FNPT, 1" FNPT
Static Pressure
300 psi (2100 kPa)
Close-Off Pressure
13 psi and 15 psi
(90 kPa and 103 kPa)
Temperature
32°F to 200°F (0°C to 93°C)
Control
2 Position
Electrical
24 VAC, 50/60 Hz
Stroke
Power Stroke 9 to 11 seconds
Spring return 4 to 5 seconds
Ambient
32°F to 125°F (0°C to 52°C)
Table 10 - 2-way Actuator
Table 11 - 2-way Valve Body
Table 12 - 3-way Actuator
Table 13 - 3-way Valve Body
Connection
C
v
X
Y
Z
3
⁄
4
"(19mm) FNPT
7.0
1
11
⁄
16
" (43mm)
11
⁄
16
" (23mm)
3
5
⁄
8
" (92mm)
*1"(25mm) FNPT
7.0
1
7
⁄
8
" (47mm)
1" (25mm)
3
11
⁄
16
" (94mm)
* 1" valve for steam only
Table 14 - EOC Connection
2
3
⁄
8
"
(61mm)
3
3
⁄
16
"
(81mm)
1
7
⁄
16
"
(37mm)
3
5
⁄
8
"
(92mm)
1
11
⁄
16
"
(43mm)
1
11
⁄
16
"
(43mm)
3
11
⁄
16
"
(94mm)
3
1
⁄
4
"
(83mm)
1
1
⁄
4
"
(32mm)
2
9
⁄
16
"
(66mm)
3
⁄
4
"
(19mm)
7
⁄
8
"
(22mm)
Figure 52 - 3-way EOC Valve
3
⁄
4
"
(19mm)
1
1
⁄
4
"
(32mm)
3
1
⁄
4
"
(83mm)
2
3
⁄
8
"
(61mm)
3
3
⁄
16
"
(81mm)
X
X
Y
Z
3
11
⁄
16
"
(94mm)
2
9
⁄
16
"
(66mm)
3
⁄
4
"
(19mm)
3
⁄
4
"
(19mm)
7
⁄
8
"
(22mm)
Figure 51 - 2-way EOC Valve
Notes:
1.
See label furnished on 2-way valve to determine direction of flow through the
valve.
2.
Adhere to the port orientation shown for the 3-way valve.
For hot water applications and chilled water/hot water (2-pipe) applications, the
2-way valve furnished is normally piped open to the coil; the 3-way valve is piped
normally open to the coil.
For chilled water applications, the 2-way valve furnished is normally piped closed
to the coil; the 3-way valve is piped normally closed to the coil.
All water coil stubs are 7/8" I.D. female sweat. Coil connections terminate 9"
(229mm) from the end of the unit. Hot water connections may be same end as
cooling coil connections, but are recommended to be opposite end to facilitate
piping. When using AAF
®
MicroTech controls, they must be opposite end.
The 2-way EOC hot water or 2-pipe CW/HW valve is furnished
normally open to the coil. When the valve is de-energized (off) there
is full flow through the coil. Energizing the valve shuts off the water
flow.
Figure 53 - 2-way EOC, Normally Open, Hot Water or 2-pipe CW/HW Valve Piping
The 3-way hot water or 2-pipe CW/HW valve is furnished normally
open to the coil. When the valve is de-energized (off) there is full flow
through the coil. Energizing the valve allows the water to bypass the
coil.
Figure 54- 3-way EOC, Normally Open, Hot Water or 2-pipe CW/HW Valve Piping
Return
Return
Balancing and Shutoff Valve
Shutoff Valve
Supply
Supply
2-way EOC
Valve
Unit Coil
Unions
A
B
Return
Return
Shutoff Valve
Shutoff Valve
Supply
Supply
3-way EOC Valve
Unit Coil
Union
Balancing
Valve
Bypass
A
B
AB
Union
Heating – Hot Water End of Cycle Valve Piping