Bell & Gossett DN0145D HS Vacuum Heating Units Series HVTM - Manual (Page 4)

4
PIPING (Returns)
Gravity return lines from 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.
Install gate valve in return line for testing pump shut off vacu-
um, closing off hot returns when cleaning strainer, etc. Do not
install check valve in return line. Avoid elbow or tee located
closer to strainer inlet than 10 times inlet diameter. If unavoid-
able relocate vacuum switches to top of nearest “dry” point on
return main unless a portion of return is below pump inlet an
accumulation tank is recommended. Accumulator tank may
not be necessary if low length of return is not lower than 24"
below pump inlet or longer than 30'. See TYPICAL PIPING-
LOW RETURNS. (Page 5) High pressure steam traps should
empty into uninsulated flash tank where condensate will cool
before entering unit.
DISCHARGE LINE
Install union, check valve, steam cock and gate valve at unit in
each discharge line. Steam cock to be adjusted to cause
pump to operate at specified pressure. If discharge line is
more than 100' long, install pipe 1 or 2 times larger than dis-
charge valve tapping.
ELECTRICAL WIRING & CONTROLS
Connect power wiring per NEC. Recheck nameplate vs. speci -
fications 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.
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.
PUTTING THE UNIT INTO SER VICE
1. Assure that the unit is piped in accordance with instructions.
2. Isolate tank before performing any system leak test. Do
not pressurize the tank as part of the leak test. Failure to
do this can result in serious injury or death.
3. Check floats for free operation.
4. Check power leads in accordance with wiring diagram
enclosed in control cabinet (when furnished).
5. Install drain plugs.
6. Fill receiver half full of water to prime pump(s) and prevent
possible damage to pump seals. Avoid freezing conditions
after unit receiver has been filled.
7. Check for proper rotation of all three phase motors.
Rotation must be clockwise looking down on the motor as
indicated by directional arrow on pump casting. If pump
runs backwards, interchange two wires (3 phase only).
8. Throttle plug cock in discharge line until pressure at pump
(while pump is discharging) approaches pump rated pres-
sure. Tighten plug nut to secure adjustment.
9. Remove start-up label (below) from panel (if applicable)
after complying with instructions.
10. If possible, observe operation thru several cycles using
selector or vacuum switch settings as noted below.
WARNING: HIGH VOLTAGE
Disconnect and lock out power before connecting or
servicing unit. Failure to follow these instructions could
result in serious injury or death.
CAUTION: DO NOT RUN DRY.
SEAL DAMAGE MAY OCCUR.
Inspect pump seal regularly for leaks. Replace as required.
Failure to follow these instructions could result in injury or
property damage.
CAUTION: DO NOT REVERSE
Reverse operation can cause extensive damage to
pumps. Jog the motor to test for direction of rotation.
Failure to follow these instructions could result in injury or
property damage. 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.
ELECTRICIAN/INSTALLER/OPERATOR
REMOVE AND DESTROY THIS TAG AFTER —
1. ASSURING THAT ALL PUMPS ROTATE CLOCKWISE PER ARROWS
CAST ON VOLUTES. (JOG PUMP MOMENTARILY TO TEST – INTER-
CHANGE ANY TWO MOTOR POWER WIRES TO REVERSE 3PH
MOTORS.)
2. ASSURING THAT SHIPPING LOCKS HAVE BEEN REMOVED FROM ALL
FLOAT SWITCHES.