Bell & Gossett DN0145D User Manual

INSTRUCTION MANUAL

DN0145

REVISION D

Hoffman Specialty

®

Vacuum Heating Units
Series HV™ (25,000-60,000 Sq. Ft. EDR)

SERIES HV UNITS

25,000-60,000 SQ. FT/. EDR

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.

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

EXPLOSIBLE

(2) All Units

DN0483 (Small) - DN0484 (Large)

INSTRUCTIONS COULD RESULT
IN SERIOUS INJURY OR DEATH.

If the decals as noted below are missing or are illegible con-

tact 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
pumps and associated systems (condensate, boiler feed, etc.).

®

WARNING

EXPLOSIBLE

ISOLATE TANK

DURING LEAK TEST

(2) All Units
DN0485 (Small)
DN0486 (Large)

HOFFMAN SPECIALTY

SERIES HV

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

DN0116 Units with Panel

TM

Morton Grove, Illinois 60053

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

2

DESCRIPTION AND INSTALLATION

The Series HV vacuum heating units are designed to serve the

dual purpose of pumping accumulated condensate back to
the boiler feed tank and maintaining vacuum in the conden­sate system. This vacuum will draw air out of the system
on start-up and facilitate the flow of steam thru the heating
system.

One pump/vacuum producer/discharge valve assembly con­trols both the condensate discharge and the production of
vacuum. Two pump (duplex) units have a second assembly for
backup and to provide extra capacity to handle peak loads.

Various electrical controls are offered to meet system require­ments. These controls are normally supplied as part of the
assembled unit and a wiring diagram is furnished with the unit.
Refer to this electrical diagram as required.

The units respond to both changing condensate levels and
system vacuum requirements.

In operation the centrifugal pump circulates water (conden­sate) thru the multi-jet nozzle creating multiple jets of water
entering the venturi. These jets entrain air and gasses creating
a smooth steady vacuum in the nozzle body and in the con­densate system. The air and gasses are separated in the
receiver and vented to atmosphere.

Low system vacuum or high water in the receiver will start the
pump to create vacuum and circulate water.

The discharge valve is opened by means of a solenoid in
response to the condensate level float switch. Controlled
opening of the discharge valve holds sufficient back pressure
in the nozzle body that the vacuum producer continues to
function even when discharging condensate (simultaneous
rating).

When the vacuum and float switches have been satisfied and
the pump stops, the check valve in the nozzle body closes,
preventing the return of air and water to the system.

An internal orifice permits the vacuum in the receiver and in
the system to slowly equalize. Note that the vent line on the
Series HV requires a check valve to prevent return of atmos­pheric air to the receiver. Without the check valve and orifice,
a system could develop high vacuum upon cooling holding the
check valve closed and thereby preventing flow of condensate
into the unit.

STRAINER

CONTROL PANEL

VENTURI

AIR VENT VALVE

FLOAT SWITCH

RECEIVER

MOUNTING PADS FOR DUPLEX
CENTRIFUGAL PUMPS

CENTRIFUGAL PUMP

MULTI-JET NOZZLE

DISCHARGE
MANIFOLD

SOLENOID
DISCHARGE VALVE

DISCHARGE

CHECK VALVE

VACUUM GAGE

DSK-1330

FIG. 1 SERIES HV VACUUM UNITS 25,000-60,000 EDR

FIG. 2 SERIES HV VACUUM PRODUCER

SOLENOID

DISCHARGE

AIR VENT

RECEIVER

MULTI-JET NOZZLES

INLET

VENTURI

DSK-1328

NOZZLE

BODY

CENTRIFUGAL PUMP

VALVE

3

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 104°F max. ambient.

Insulate or ventilate as required.

PIPING (GENERAL)

Pipe the unit per the Elementary Piping Diagram. Locate and

support piping so as to not load the discharge valve.

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
feet vertical height unless an overflow connection is provided.

Series HV Units require a check valve in the vent line as shown
on the piping diagram (furnished with unit).

PRIMING PORT

Provide a priming port as shown on piping diagram. Provide a

water supply for priming.

FLOAT SWITCHES

Floats are locked in place to prevent damage during shipment.

Remove shipping locks. Check factory settings. Floats are
adjustable for various levels of operation.

See page 7 for detailed instructions.

EQUALIZING LINE

An equalizing line must be installed with all Series HV units.

This line must be installed to prevent formation of a vacuum
on the radiation side of the system when steam stops flowing
in the mains. This vacuum may be higher than return line vac­uum, which would prevent condensate from flowing back to
the pump. To correct this in an unzoned system, install equal­izer line as shown in the piping diagram. To correct this in a
zoned system, install equalizer line for each zoned section or
install a vacuum breaker on supply line on radiation side of
each zone control valve.

CAUTION: UNIT LIFTING EYE

Use unit lifting eyes only to lift unit as shipped from

factory. Unit must be empty and disconnected from pipes,
anchors and other restraints. Use proper rigging pro­cedures. Failure to follow these instructions could result in
injury or property damage.

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: 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.

TO BOILER
FEED
SYSTEM

REDUCER

STRAINER

SERIES VLR DUPLEX

PIPING DIAGRAM

DRAIN

DRAIN

DRAIN

DV

PRIMING

OPENING

EQUALIZING LINE —

3

/4"

BOILER

FROM BOILER
FEED SYSTEM

— GATE VALVE

— DISCHARGE VALVE

DV

— STEAM OR PLUG COCK
— UNION

— CHECK VALVE

OPEN VENT ABOVE
BOILER WATER LINE

RETURN FROM
HEATING SYSTEM

EQUALIZING CONNECTIONS FOR ZONED SYSTEMS

ZONE CONTROL

VALVE

STEAM MAIN

M

TO ZONE

RETURN MAIN

FIG. 3
SERIES HV PIPING DIAGRAM