Dwyer TVF User Manual
Page 7
APPARENT METER
READING
MIGRATION (reading
changes but flow
appears constant)
LEAKAGE
Frequently caused by use of soft disc type valves,
which may need to be replaced with a valve more
suited to flow control.
Can also be indicative of changing fluid conditions
(density, viscosity, etc.). Problems with other
elements of the flow system, including leaks, clogged
filters, pump/compressor wear, etc. may first appear
as a change in meter reading — one of the functions
of a flowmeter.
If at the junction of the body and sight tube, it is
indicative of either (a) damaged O-ring (most
common); (b) damaged sight tube; or (c) damage to
the gland section of the body. It may also be caused
by improper reassembly of the flowmeter in the field.
If there is leakage at the pipe connections to the
meter, it is probably caused from over-tightening
pipes on a prior installation (or the initial installation.
Verifying the proper fluid conditions are known and
applying correction formulae as needed will remedy
problems associated with changing fluids. Cleaning,
servicing, and replacement and/or repair of other system
components may be required.
Replace any damaged parts immediately; using the
proper assembly procedures indicated in this instruction
and the assembly detail drawings.
Remove the body and inspect for damage — if none is
visible, check pipe threads, reapply proper thread
lubricant/sealant, and reinstall.
If leak persists, replace meter body.
Note: All Series TVF flowmeters are hydrostatically pressure tested before they are shipped. Dwyer Instruments, Inc. encourages you
to contact the factory with any questions regarding proper installation and operation of Series TVF flowmeters.