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Section 3
Rev. 06/15
Safety, Installation, Operations & Service Manual
DOPSM2080X012
A regulator is not intended to be used as a shutoff device. When the regulator is not 
in use, the inlet supply should be turned off. As a safety precaution, a pressure relief 
device should be installed downstream of the regulator.
3.3.4 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 
regulator removed from the line. However, in some cases repair may be accomplished 
without removal of the regulator body as long as the supply has been shut off and the inlet 
and outlet pressures have been vented.
An Assembly Drawing and Bill of Material for the regulator 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 pg. 39 for TESCOM contact information).
The following steps outline the disassembly of pressure reducing regulators for 
maintenance and repair:
1.  Clamp the regulator in a vise by the flats on the bottom and/or side of the regulator 
body.
2.  Turn control knob and/or spring adjustment mechanism counterclockwise to insure 
removal of all spring force on the piston.
NOTE: (Dome loaded regulators): All pressurized gas or liquid must be vented from dome 
before disassembly.
3.  Remove upper portion of regulator (bonnet and/or dome). Some models require the 
hand knob and/or mounting bracket to be removed first.
NOTE: Upper portion of regulator may also include spring button, load spring back-up 
plate, and piston sensor, etc. Review correct drawing to ensure that all parts have been 
disassembled.
NOTE: (Two-Stage Regulator) TESCOM Model Series BB-5 is a two-stage regulator that 
has portions on both ends of the regulator body that must be removed. It is TESCOM’s 
recommendation that two-stage regulators be returned to the factory for repair.
4.  The valve parts can now be removed from the regulator body by turning the seat 
retainer and/or back cap counterclockwise until it is free of the regulator body. 
TESCOM Models 26-1000 and 44-1100 valve parts are held in place by the use of left-
handed threads.
When removing valve parts from a regulator that has a back cap, care must be taken 
to insure the main valve stem remains vertical. If the main valve stem is not removed 
correctly, parts may remain in the regulator.
5.  To disassemble main valve assembly and/or valve, clamp valve in smoothed jaw vise. 
Clamping should be done on flats.