Dwyer LFM User Manual
Dwyer instruments, inc, Series lfm in-line and panel mount flowmeter
The Series LFM In-Line Flowmeter measures the flow of
water and other compatible media. Models possess dual GPM
and LPM scales. Various size ranges and connections are
available to satisfy your application.
INSTALLATION
1. Select an indoor (only) location that is free from excess
vibration, within the specified temperature limits, and away
from direct sunlight.
2. Handle carefully. Hand-tighten flange nut connection rings.
O-Rings will seal if hand tightened only. Do not overtighten the
adapters and fittings.
3. Install the flowmeter in an exact vertical plane, one that is in
proper alignment with the existing plumbing. Use wall or other
structural supports at the top and bottom of the unit. Do not
allow the instrument to support the weight of pipes or tubing.
4. Use plumbers tape thread sealant. Do not use pipe dope
compounds, which can craze and crack housing. Hand tight-
en system pipe fitting to adapter fitting. If additional torque is
needed to seal pipe joint, use strap wrench on adapter fitting.
5. If using solvent-based glues like PVC cement, in the piping
system, do so with the meter’s body removed until glue has
cured, then purge the system before re-installing. Do not sol-
der brass fittings with the body installed, because the heat
generated to solder the brass fittings will damage the flowme-
ter.
CAUTION: Ball valves and solenoid valves can have a “water
cannon” effect on opening, creating pressure that exceeds the
warrantied ratings and will damage the flowmeter.
SPECIFICATIONS
Service: Compatible liquids.
Wetted Materials: See chart.
Temperature Limits: See chart. Varies with pressure.
Pressure Limit: See chart. Varies with temperature.
Accuracy: ±5% full scale.
Process Connections: Various male and female NPT, metric
union connectors, and 90° male NPT elbow fittings available
depending on model series.
OPERATION AND MAINTENANCE
Once installed, the Series LFM In-Line and Panel Mount
Flowmeter is self-operating and requires no maintenance other
than an occasional cleaning with mild soap and a bottle brush.
For this purpose, the unit has been designed so that its body
can be removed quickly and easily while leaving all fittings
intact.
When removing float for cleaning, note the floats “up” position.
The float is a precision part and must be reassembled without
adverse treatment, i.e. dropping, denting, and surface abra-
sion.
The standard technique for reading a Variable Area Flowmeter
is to locate the of greatest or widest diameter on the float, and
then align that with the theoretical center of the scale gradua-
tion. In the event that the float is not aligned with a grad, an
extrapolation of the float location must be made by the opera-
tor as to its location between the two closest grads.
Series LFM In-Line and Panel Mount Flowmeter
Specifications - Installation and Operating Instructions
Bulletin V-31
DWYER INSTRUMENTS, INC.
Phone: 219/879-8000
www.dwyer-inst.com
P.O. BOX 373 • MICHIGAN CITY, IN 46361, U.S.A.
Fax: 219/872-9057
e-mail: [email protected]
Model
LFMA
LFMB
LFMC
LFMD
LFME
LFMF
A
3-15/16
(100.01)
6-5/16
(160.34)
5-9/32
(134.14)
6-45/64
(170.26)
8-55/64
(225.03)
11-27/64
(290.12)
B
ш1-21/32
(ш42.07)
ш1-63/64
(ш50.40)
ш1-63/64
(ш50.40)
ш2-21/64
(ш59.13)
ш2-27/32
(ш72.23)
ш3-15/16
(ш100.01)
C
6-45/64
(170.26)
8-55/64
(225.03)
8-9/32
(210.34)
9-27/32
(250.03)
12-19/64
(312.34)
15-3/4
(400.05)
D
8-55/64
(225.03)
7-11/16
(195.26)
10-41/64
(270.27)
12-51/64
(325.04)
E
63/64
(25)
63/64
(25)
63/64
(25)
1-15/64
(31.35)
F
2-15/64
(56.75)
2-15/64
(56.75)
51/64
(20.24)
63/64
(25)
NPT
1/2 NPT
1/2 NPT
1/2 NPT
3/4 NPT
1 NPT
2 NPT
V-31 12/5/06 9:40 AM Page 1