HEIL PT 1000, Operation Manual

Page: 177 / 202

Issued September 2017
Compressed Natural Gas (CNG) Option Copyright 2017, Heil Environmental
Printed in U.S.A.
169
TRANSFER FUELING (DEFUELING) MODES,
COMPONENTS AND PROCEDURES
(CONTINUED)
A. CNG Fuel Module Defueling Functions
The fuel module is equipped with a defueling
functionality. This allows the transfer of CNG fuel into
the fill receptacle of a second CNG vehicle, using a
defueling hose, or capturing of CNG fuel in a system
that can send it back to a CNG fueling station storage
facility for reuse.
NOTICE
The defueling process does not deplete the CNG fuel in
the supplying (defueling) vehicle. The pressure in both
tanks will be equalized with CNG fuel after the defueling
process is completed. To completely deplete the CNG fuel
from a vehicle, the defueling hose can be connected to a
CNG fuel recovery system instead of a second vehicle.
B. CNG Fuel Module Defueling Operating Modes
When the Defueling Selector Valve is positioned to the
“Normal Operation” position, the defueling receptacle is
vented to the atmosphere to allow disconnection of the
defueling hose.
When the Defueling Control Valve is positioned to the
“Defueling Enabled” position, CNG fuel from the storage
tanks can flow to the Defueling Receptacle.
Figure 84. Fuel Module Defueling
Selector Valve Set
C.CNG Fuel Module Defueling Components
Defueling components are located on the front panel of
the fuel module. The components include:
1. Defueling Receptacle – connection point for
transferring CNG fuel out of the fuel system.
2. Defueling Selector Valve – facilitates CNG fuel
transfer
Figure 85. Fuel Module Defueling Components