Bell & Gossett DN0136C Domestic Pump Vacuum Heating Units Series VCL - Manual (Page 12)

Xylem Inc.
8200 N. Austin Avenue
Morton Grove, Illinois 60053
Phone: (847) 966-3700
Fax: (847) 965-8379
www.xyleminc.com/brands/bellgossett
Bell & Gossett is a trademark of Xylem Inc. or one of its subsidiaries.
© 2012 Xylem Inc. DN0136C November 2012
DEALER SER VICE
If tr ouble occurs that cannot be rectified, contact your local
B&G representative. He will need the following information in
order to give you assistance.
1. Complete nameplate data of pump and motor.
SEE RATING NAMEPLATE at right.
2. Suction and discharge pipe pressure gauge readings.
3. Ampere draw of the motor.
4. A sketch of the pump hook-up and piping.
5. Provide complete information on boiler control switches
and any motorized or solenoid valves in the boiler feed
piping.
SYSTEM IS NOISY
1. Banging in the steam mains is usually caused by “implod-
ing” in condensate lying in low points in lines. These
pockets can be eliminated by dripping low points, properly
supporting the pipe, or by increasing the pitch of the lines.
2. Improper dripping of the steam mains and risers; where
there is a rise in the steam main, or where it branches off
into a riser, a drip trap must be installed to the drain line.
3. The piping is too small to drain properly.
4. A defective trap is holding condensate in steam supply line.
PUMP DOES NOT RETURN ALL CONDENSA TE
TO BOILER FEED SYSTEM (PUMP FLOODS)
1. Pump is running backward looking down on motor.
Rotation of 3 phase motors may be corrected by inter-
changing any two of the three wires. Pump should run
clockwise.
2. Steam traps are blowing through causing condensate to
return at excessive temperatures. This may reduce the
capacity of pump below its rating, depending on the unit
and type of pump furnished. Traps should be repaired or
replaced.
3. The total pressure at the pump discharge is greater than the
pressure for which the pump was designed. Check the total
pressure which includes the boiler pressure, the friction
head and the static head.
4. A valve in the discharge line between pump and boiler is
closed or throttled too tightly. Check valve is installed
backwards.
5. Condensate is held up in system periodically by induced
vacuum in boiler or radiation then released in a flood when
pump starts. Install equalizer line per piping diagram.
6. The strainer is dirty thus retarding flow. Refer to instructions
for cleaning.
7. The impeller eye is clogged with trash.
8. Systems with accumulator tanks should have equalizer line
run from accumulator tank to steam header as shown on
pages 2 & 3: NOT from accumulator tank to pump receiver
NOR from pump receiver to steam header. Install vacuum
breaker on accumulator tank, NOT on pump.
9. Pump is too small for the system.
Bell & Gossett
Morton Grove, Illinois 60053
DOMESTIC ® PUMPS