Specifications

Part Number STH12 9/10 125
Water Booster System
Qualifier
Probable
Cause
Corrective Action
Low or no water pressure at noncarbonated beverages
Water Booster will
not cycle ON. Both
the pressurized
filter water and
filtered water
pressure register
55 psi (3.8 bar).
No power to
Water Booster
Pump.
Verify Toggle Switch for “Booster
Pump” is in the ON position and main
power supply is ON.
Pressure Switch
defective.
Remove Pressure Switch Cover and
use a voltmeter across terminals to
determine whether “open” or “closed”.
If in the “open” position, replace
Switch.
Motor defective. If Motor will not operate, verify voltage
across Motor Terminals with a
voltmeter. If voltage reads from 110 to
120 VAC, the Motor is defective and
should be replaced.
Pump frozen. Loosen the Coupling Clamp with a
flat-blade screwdriver and disengage
pump from Motor. Turn the Coupling
key by hand, in back of pump. If pump
shaft will not spin freely, Pump is
defective and must be replaced.
Water Booster
cycles ON and OFF
and pressurized
Filtered Water
Gauged readings
range between
65 psi (4.6 kg/cm
2
)
to 85 psi
(6.0 kg/cm
2
).
Water supply
shut-off after
Booster
System.
Examine Shut-off Valve to “Plain
Water to Unit” and “Water to Coffee
Machine” and ensure both are in the
ON position.
Frozen Water
Coil.
Refer to Troubleshooting
“Refrigeration System” under No
carbonated water at any of the
dispensing valves (freeze up).
Pump and Motor
will not cycle OFF.
Water supply to
Booster Pump
shut OFF.
Examine the Shut-off Valve to Booster
Pump and ensure valve is in the ON
position.
Restricted
Water Filter.
Observe Filter Water Pressure Gauge.
If pressure drops total of 40 psi
(2.8 bar) or more when pump cycles
ON. Replace filter.
Leak on Booster
System Pump
Strainer
obstructed.
Locate water leaks on system and
repair. Remove Pump Strainer at
Brass Booster Pump, flush screen
with water to clean. Reassemble and
position in place. Replace screen if
necessary.
Pump Coupling
Key defective.
Using a flat-blade screwdriver, loosen
Coupling Clamp and disengage Pump
from Motor. Examine Coupling Key, if
rounded off on either end, replace.
Pump defective. Examine Pressurized Filter Water
Pressure Gauge. If Pump and Motor
continue to operate but fail to build up
to 85 psi (6.0 kg/cm
2
) in order to cut
off, pump is defective. Replace Pump.
Pressure Switch
improperly
adjusted or
defective.
Observe Pressurized Filtered Water
Pressure Gauge to ensure proper
cycle ON at 65 psi (4.6 kg/cm
2
) and
cycle OFF at 85 psi (6.0 kg/cm
2
).
Refer to instructions found under
Switch Cover for adjusting. If Switch
does not respond to adjustment,
replace switch.