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Domestic® Pump
Underground Condensate
and Boiler Feed Units
INSTRUCTION MANUAL
DN0129
REVISION D
Series CU,™ CMU
™
INSTALLER: PLEASE LEAVE THIS MANUAL FOR THE OWNER’S USE.
SAFETY
INSTRUCTIONS
This safety alert symbol will be used in this manual and on
the unit safety instruction decals to draw attention to safety
related instructions. When used, the safety alert symbol means
ATTENTION! BECOME ALERT! YOUR SAFETY IS INVOLVED!
FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT
IN A SAFETY HAZARD.
If the decals as noted below are missing or are illegible contact
your local B&G representative for a replacement.
1. Electrical connections to be made by qualified Electrician in
accordance with all National, State and Local codes.
2. Motor must have properly sized starter with properly sized
heaters to provide overload and undervoltage protection.
3. If pump, motor or piping are operating at extremely high or
low temperatures, guarding or insulation is required.
4. Operating personnel should be trained in the operation of
Condensate and/or Boiler Feed Units.
EXPLOSIBLE
(2) All Units
DN0483 (Small) - DN0484 (Large)
WARNING
DO NOT PRESSURIZE TANK.
ISOLATE TANK DURING LEAK TEST.
DO NOT RESTRICT VENT.
DO NOT PLUG OVERFLOW.
OPEN INLET VALVES SLOWLY.
DO NOT USE AS A FLASH TANK.
FAILURE TO FOLLOW
INSTRUCTIONS COULD RESULT
IN SERIOUS INJURY OR DEATH.
WARNING
EXPLOSIBLE
ISOLATE TANK
DURING LEAK TEST
(2) All Units
DN0485 (Small)
DN0486 (Large)
TM
SERIES
MODEL
SERIAL
GPM PSI PUMP
CFM IN HG. PUMP
DWGS
POWER V. PH. HZ 60
CONTROL V. PH. 1 HZ 60
TOTAL LARGEST MOTOR
F.L. AMP F.L. AMP
DN0016
TM
Morton Grove, Illinois 60053
DN0116
Units with Panel
TM
SERIES
MODEL
SERIAL
GPM PSI PUMP
POWER V. PH. HZ60
CONTROL V. PH. 1 HZ60
TOTAL LARGEST MOTOR
F.L. AMP F.L. AMP
TM
Morton Grove, Illinois 60053
DN0019
Units Less/Panel
CAUTION
DO NOT RUN PUMP DRY,
SEAL DAMAGE MAY OCCUR.
INSPECT PUMP SEAL
REGULARLY FOR LEAKS,
REPLACE AS REQUIRED.
FOR LUBRICATION
REQUIREMENTS, CONSULT
SERVICE INSTRUCTIONS.
FAILURE TO FOLLOW
INSTRUCTIONS COULD
RESULT IN INJURY OR
PROPERTY DAMAGE.
P70644
All Units
P70644
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2
DESCRIPTION
Series CU condensate units have one (simplex) or two (duplex)
pumps which are controlled by a float(s) switch or mechanical
alternator switch in the receiver.
These pumps return accumulated condensate to the boiler
feed system.
Series CMU boiler feed units have one (simplex) or two (duplex)
pumps which are controlled by boiler system controllers. Series
CMU receivers are sized to provide for accumulating system
surges of condensate. Water makeup valves are also included
to insure that water is always available to meet boiler demands.
Receivers are non-code cast iron.
PRELIMINARY INSPECTION
Assure that there is no shipping damage.
Assure that nameplate ratings agree with job specifications and
actual conditions.
HANDLING
Use care in installing unit.
LOCATION
Place unit for easy access to all parts. Allow adequate space
for servicing. Check ambient conditions.
NOTICE / TEMPERATURE LIMITS
Motors are designed to operate in 104ºF (40°C) max. ambient.
Insulate or ventilate as required.
PIPING (General)
Pipe the unit per the Elementary Piping Diagram. Locate and
support piping so as not to load the pump discharge.
PIPING (Returns)
Gravity return lines from the system must be properly pitched
down to unit inlet. Returns must also be trapped to prevent steam entry into the unit. An inlet basket strainer is
recommended.
PIPING (Vent)
Install a vent pipe to atmosphere. Pipe to be size of vent port
on unit. Do not restrict or reduce vent opening or exceed 20
inch vertical height unless an overflow connection is provided.
FLOAT SWITCHES AND MECHANICAL ALTERNATORS
The floats which operate these swithces are factory set but can
be field readjusted as required.
Adjustment is made by removing the float switch as an assem-
bly and readjusting the stop collars on the float rod.
Setting should utilize as much of the tank volume as practical.
Settings should avoid “short cycling” of the pump. See page 3
for detailed instructions.
ELECTRICAL WIRING & CONTROLS
Connect power wiring per NEC. Rechceck nameplate vs. spec-
ifications and conditions. All single phase motors have internal
thermal protection.
Three phase motors must use starters with properly sized overload relays. Overload relays furnished are designed for manual
reset.
AIR VENT
TO DRAIN
UNION
CHECK VALVE
GATE VALVE
STEAM COCK
DISCHARGE
CONDENSATE
RETURN LINE
UNDERGROUND
CONDENSATE
RETURN LINE
BASKET
STRAINER
(OPTIONAL)
UNION
TO DRAIN
IDPD33
AIR VENT
TO DRAIN
WATER LINE
OF BOILER
UNION
CHECK VALVE
GATE VALVE
STEAM COCK
WATER MAKE-UP
WITH 3 VALVE BYPASS
OPTIONAL
DISCHARGE TO BOILER
DETAIL AA
WATER
MAKE-UP
SUPPLY
(SEE DETAIL AA)
CONDENSATE
RETURN LINE
UNDERGROUND
CONDENSATE
RETURN LINE
BASKET
STRAINER
UNION
TO DRAIN
IDPD44
SERIES CU – CONDENSATE UNIT SERIES CMU BOILER FEED UNIT
REPRESENTATIVE PIPING DIAGRAMS
WARNING: EXPLOSIBLE
Do not pressurize receiver. Isolate receiver during leak
test. Do not plug overflow. Do not restrict vent opening to
atmosphere. Open valves slowly. Failure to follow these
instructions could result in serious injury or death.
CAUTION: NOT A CHEMICAL PUMP
Inject boiler feed compounds from chemical feed tank
into boiler feed piping – never into condensate tank. Failure
to follow these instructions could result in injury or property
damage.
WARNING: HIGH VOLTAGE ELECTRICITY
Disconnect and lock out power before connecting or
servicing unit. Failure to follow these instructions could
result in serious injury or death.
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3
FLOAT SWITCH ADJUSTMENT
The float positions are factory set. These positions should be
reset as necessary. Minor deviation is permissible to meet local
requirements. The settings must avoid “short cycling” of the
pumps.
The float switch and mechanical alternator each have an internal compensating spring to balance the weight of the float
guide rod. These springs are to have just enough tension or
compression on the float switch to counterbalance the guide
rod (but not the float).
PIPING DIAGRAMS VACUUM TIGHT
UNDERGROUND CONDENSATE &
BOILER FEED UNITS
Type CVU units are designed for use as a mechanical lift in a
vacuum heating system. They are also used to return condensate under vacuum to a boiler feed tank. They have vacuum
tight displacer switch(es) for pump control.
Type CMVU units have water make-up valve and are actuated
by boiler controller. They are designed for use in a vacuum system to discharge condensate directly to the boiler.
It is necessary to pipe the vent line to atmosphere using full
vent port size piping with check valves installed as shown on
diagrams. It is also recommended that the vent line be
“dripped” to drain to prevent an accumulation of condensate in
the vent pipe.
*MAKE SETTINGS
WITH ARM AT
HIGHEST POSITION
MECHANICAL
ALTERNATOR
FLOAT SWITCH
2DFS01
PIPING DIAGRAM FOR UNDERGROUND
CONDENSATE UNIT USED
IN A VACUUM SYSTEM
PIPING DIAGRAM FOR UNDERGROUND
BOILER FEED UNIT USED
IN A VACUUM SYSTEM
FLOAT SETTING CHART
Condensate Unit
Single Duplex Duplex 2 Float Switch Boiler
Primary Stand-By
Feed
Unit (Mech. Alt.) Float Switch Float Switch Unit
Depth “A”“B”“A”“B”“A”“B”“A”“B”“A”“B”
36" 11" 22" 81/2" 21" 121/2" 22" 11" 22" 14" 22"
48" 11" 34" 81/2" 33" 121/2" 34" 11" 34" 26" 34"