
FRX 50 STAINLESS STEEL CENTRIFUGAL PUMP 
FRX 50-R POLYPHENYLENE SULFIDE CENTRIFUGAL 
INSTALLATION, OPERATION, AND REPAIR MANUAL
Models FRX 50 & FRX 50-R are high 
performance centrifugal pumps. 
The pumps are ideal for marine,
ndustrial, agricultural or commercial
i 
applications. The FRX 50 model 
features all 316 stainless steel 
components for superior corrosion 
resistance when pumping chemical 
compounds. FRX 50-R has 
polyphenylene sulfide housing & 
cover. A carbon/ceramic/viton bellows 
seal is standard. FRX 50 ports are 1/2" 
NPT/1" Hose. FRX50-R has 1" hose 
connections.
FRX 50
FRX 50-R
GENERAL SAFETY INFORMATION:
THE FOLLOWING WARNINGS ARE USED TO NOTIFY AND ADVISE THE USER OF THIS PRODUCT OF 
PROCEDURES THAT MAY BE DANGEROUS TO THE USER OR RESULT IN DAMAGE TO THE PRODUCT.
THIS BULLETIN MUST BE READ COMPLETELY BEFORE INSTALLING, OPERATING, OR SERVICING, 
THE PUMP. 
• DO NOT perform service or maintenance 
when the pumping system is pressurized. 
Injury or death may occur.
• DO NOT operate the pump in a manner 
that it was not intended to be used.
• DO NOT mount the pump such that high 
piping loads exist on the pump flanges, or 
in a rigid piping system that does not allow 
the pipe to expand and cause the pump to 
be strained.
ALLATION:
INST
Install the pump wher
e the inlet is below the liquid level. A valve may be used to isolate the
• DO NOT continue to operate the pumping 
system when a known leak exists.
• DO NOT continue to operate the pump 
when unusual noise or vibration occurs.
• DO NOT operate beyond the pressure or 
temperature limits stated in the product 
literature. See Form 8110.
• DO NOT allow severe temperature changes 
to occur in a short time period within the 
pumping system.
pump for service. The pump is not self-priming and needs the inlet to be flooded at start-up. 
The motor is splash r
esistant, not submersible, and should be located in a dr
y envir
onment. 
FORM 3810A (09-07)

PIPING/MOUNTING:
The pump inlet and outlet has 1/2" NPT - 1" hose connections. 
Use pipe sealant on the threads and other connections. The 
base does not require direct mounting if one of the pipe 
flanges is rigid mounted. Do not rigid mount both the flanges 
and the base to avoid mounting tolerances that may distort
he motor base. Install the pump with the shaft in a 
t 
horizontal direction. 
Never install the pump vertical with the motor below the 
pump.
OPERATION:
The pump should be operated with liquid in the pump 
otherwise seal damage may occur. If an inlet valve is present, 
the valve should always be completely open during 
operation to avoid cavitation. An outlet valve may be used to 
throttle the flow rate. Avoid repeated starts and stops; the
ump can operate for a long period of time without any flow.
p 
DC motors are brush type and may emit a noise from the 
brush that can sound like a squeal, this is normal. The pump 
will be extremely quiet unless there is air in the system.
ELECTRICAL:
The motor must be protected from over current by using a 
fuse or circuit breaker (see chart below for correct protection). 
The proper minimum wire size is stated for each voltage
pplication. Make sure that the pump has the proper voltage
a 
rating to match the installation power. Do not use or install if 
the voltage on the label is different than the installation. All 
wire connections must be secure and sealed to protect 
arcing. Follow all local installation codes.
MOTOR VOLTAGE FUSE/CB  WIRE SIZE
ON NAME PLA
12VDC 15 14
24VDC 10 16 
110VAC 2 18 
230VAC 1 18
TE  AMPS  AWG
REPAIR AND MAINTENANCE:
The pump has a carbon/ceramic seal that may last several 
thousand hours based upon the application. The motor is not 
rebuildable after the brushes (DC) have worn to the limits. A
eal that leaks will show leakage through the slot between the
s 
pump housing and the motor. Extreme leakage may damage 
the motor bearings and contaminate the inside of the motor.
FORM 3810A (09-07)