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Installation Manual
Content
December 2020
Installation Manual
TR000238ENUS-01_12-20
Valves - TESCOM On-Off and Diverting Valves
General
TESCOM On-Off and Diverting Valves are specifically engineered for application requiring
dependable controls. These valves are especially appropriate for installations where high
system pressures (up to 10,000 psig) are used.
Actuation Types
The valve is closed or opened by applying low air pressure to the actuation port.
Operation (Control Knob Adjustment)
The normally closed (spring closed) VA and VG valves require a minimum pressure of 60
psi applied to the actuation port to open. The normally open (spring open) VA and VG
valves require a minimum pressure of 60 psi applied to actuation port to close. Most other
valves, including the VL, VM, VT, and VU valves require a minimum pressure of 80 psi for
actuation pressure. Please check your drawings for the maximum actuation pressure.
TESCOM valves will operate with any liquid or gaseous media compatible with the wetted
materials. A filter is recommended for use in all but the cleanest media. Gaseous media
should be free of excessive moisture to prevent icing of the valve at high flow rates.
Maintenance
The following procedures are provided to enable the customer to perform all normal
maintenance and repair operations. These operations are more easily performed with
the valve removed from the line. However, in some cases repair may be accomplished
without removal of the valve body as long as the supply has been shut off and the inlet
and outlet pressures have been vented.
The following steps outline the disassembly of the On-Off and Diverting Valves for
maintenance and repair. For field repairs and maintenance, it is recommended to use the
valve modules for repair. Module numbers are located on the datasheets or call TESCOM
for the module number.
An Assembly Drawing and Bill of Material for the valve will be needed to complete
maintenance procedures. The Assembly Drawing and Bill of Material are separate from
this manual and available by contacting TESCOM (see last page for TESCOM contact
information).
S
pecial repair tools are available for field servicing valve modules (P/N 64084 for VA
module and JT103871 for VG module):
1. Clamp the valve body in a vise.
2. Remove the upper portion of the valve bonnet. The actuation side.
3. For the VT and VU valves, also remove the lower bonnet.
3.6.1
3.6.2
3.6.3
3.6.4
3.6
