Bell & Gossett DN0412C HS Vented Boiler Feed Units Series HSM - Manual (Page 4)

4
TROUBLE SHOOTING PROCEDURES
All units are thoroughly tested at the factory before shipment. They
should operate satisfactorily without further adjustment if properly
installed and provided they have not been damaged by rough handling
in transit. If system or unit performance is not satisfactory, refer to the
following check list.
Pump Will Not Start
1. The power supply has been interrupted, disconnect switch is open
or selector switch is improperly positioned.
2. Incorrect voltage for motor. Check voltage and wiring with motor
characteristics.
3. Incorrect starter coil for power supply.
4. The overload relays and the starter have tripped out and must be
reset. Ambient temperature may be too high.
5. Check pump controls or other controls for proper operation.
6. Wiring to control cabinet is incorrect or connections are loose.
7. The basket strainer is dirty thus restricting flow into the receiver.
Clean periodically.
8. Boiler is full or boiler control switch is defective.
9. The low water cut-off float switch is open due to low water, incor-
rect adjustment or failure.
Pumps Runs Continuously
1. Pump is running backward. Rotation of three phase motors may be
corrected by interchanging any two of the three wires. Rotation
should be clockwise looking down on motor.
2. Steam traps are blowing through causing condensate to return at
excessive temperatures. This may reduce the capacity of pump
below its rating. Traps should be repaired or replaced.
3. Pump discharge pressure is less than operating pressure of the
boiler.
4. The total required pressure at the pump discharge is greater than
the pressure for which the pump was designed. Check the total
pressure which includes atmospheric pressure, the friction head
and the static head.
5. A valve in the discharge line is closed or throttled too tightly. Check
valve is installed backwards.
6. The impeller eye is clogged.
7. Pump is too small for system.
Boiler Feed Pump is Noisy
1. The pump is working against a lower pressure than designed for.
While pump is discharging, adjust plug cock in discharge line until
pressure at pump approaches pump rated pressure.
2. Excessive condensate temperature. Correct system conditions. How-
ever, this applies to certain units only; others are designed to handle
boiling water.
3. Magnetic hum or bearing noise in motor. Consult motor manufac-
turer's authorized serviced station nearest unit location.
4. Starter chatters. Trouble is caused by low line voltage, poor con-
nections, defective starter coil, or burned contacts.
5. Pump is running backward.
The System is Noisy
1. Banging in the steam mains is usually caused by steam “imploding”
in condensate lying in low points in lines. These problems 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 in the drain line.
3. The piping is too small to drain properly.
4. A defective steam trap is holding condensate in steam supply line.
5. Defective check valve permits steam, to vent thru pump into the
boiler feed tank.
6. A priming boiler is discharging water with the steam. Consult boiler
manufacturer.
Excessive Water Overflow From Unit
1. Receiver sized too small to accommodate system surges.
2. Water make-up valve open or float set too high.
3. Water make-up valve leaks.
Morton Grove, Illinois 60053
TM SERIES HCM
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
DEALER SER VICING
If trouble occurs that cannot be rectified, contact your local B&G rep -
resentative. He will need the following information in order to give you
assistance.
1. Complete nameplate data of pump and motor. SEE RATING
NAMEPLATE.
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.
HOFFMAN SPECIALTY ®