A9 Valve Operation
Downstream Pressure
➀
must be sufficient to
keep Adjustment Spring
➁
from opening Valve
Port
➂
. If receiver pressure falls below the spring
set point, the valve port opens, allowing Upstream
Pressure
➃
to fill the Valve Chamber
➄
, opening
the Main Valve
➅
(one full turn = 25 psig
change).
A9B Valve
Racks equipped with an A9B Valve have no
Bypass Solenoid for Koolgas Defrost operation.
The single A9B valve covers both functions.
A9B Valve Operation
When the Solenoid is de-energized the valve
operates like the standard A9. When the sole-
noid is energized the Solenoid Port
➀
opens,
filling the Valve Chamber
➁
, and opening the
Main Valve
➂
(one full turn = 25 psig change).
Table 6-6 — Troubleshooting
Receiver Pressure Regulator
September 1, 1997
P/N 401789
6 - 11
HUSSM ANN CORPORATION • BRIDGETON, M O 63044-2483 • Printed in USA
Figure 6-13 — A9 Receiver Pressure Regulator
Figure 6-14 — A9B Receiver Pressure Regulator
with Solenoid and Pilot Port
Malfunction
Cause
Action
Fails to Open
Set too high
Reduce spring tension
Dirt blocking Valve Port
Clean or replace
Diaphragm dirty or misaligned
Clean, replace or align
Fails to close
Set too low
Increase spring tension
Dirt in bleed port
Clean or replace
Installed backwards
Re-install with direction of flow
1
2
4
6
3
5
3
1
2
De-energized
Return to Contents