Groen NGB/3 Series, NGB/3/E Series Operator's Manual

? IMPORTANT INFORMATION ? KEEP FOR OPERATOR ? IMPORTANT INFORMATION ?

OPERATOR MANUAL OM-NGB/3

Part Number 121003 DOMESTIC

Model: NGB/3, NGB/3/E

Steam Boilers

Gas Heated
200,000 BTU/hr firing rate
120,000 BTU into product

3.7 effective boiler horsepower

FOR YOUR SAFETY
DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPORS AND LIQUIDS IN THE
VICINITY OF THIS OR ANY OTHER APPLIANCE.

READ THE INSTALLATION, OPERATING AND MAINTENANCE INSTRUCTIONS THOROUGHLY
BEFORE INSTALLING, OPERATING OR SERVICING THIS EQUIPMENT.

POST IN A PROMINENT LOCATION
INSTRUCTIONS TO BE FOLLOWED IN THE EVENT USER SMELLS GAS. THIS INFORMATION
SHALL BE OBTAINED BY CONSULTING YOUR LOCAL GAS SUPPLIER. AS A MINIMUM,
IMMEDIATELY TURN OFF THE GAS AND CALL YOUR GAS COMPANY AND YOUR
AUTHORIZED SERVICE AGENT. EVACUATE ALL PERSONNEL FROM THE AREA.

WARNING
IMPROPER INSTALLATION, ADJUSTMENT, ALTERATION, SERVICE OR MAINTENANCE CAN
CAUSE PROPERTY DAMAGE, INJURY OR DEATH.

Information contained in this document is
known to be current and accurate at the time
of printing/creation. Unified Brands recom­mends referencing our product line websites,
unifiedbrands.net, for the most updated
product information and specifications.

OM-NGB/3

IMPORTANT — READ FIRST — IMPORTANT

WARNING: THE UNIT MUST BE INSTALLED BY PERSONNEL QUALIFIED TO WORK WITH GAS,

ELECTRICITY AND PLUMBING. IMPROPER INSTALLATION CAN CAUSE INJURY TO
PERSONNEL AND/OR DAMAGE TO THE EQUIPMENT. THE UNIT MUST BE INSTALLED IN

ACCORDANCE WITH APPLICABLE CODES.
CAUTION: AN ELECTRICAL GROUND IS REQUIRED.
CAUTION: DO NOT LOCATE THE BOILER CABINET DIRECTLY OVER A FLOOR DRAIN OR FLOOR

SINK. HUMIDITY OR WATER FROM A DRAIN WILL DAMAGE ELECTRICAL PARTS OF A

UNIT.

WARNING: TO AVOID DAMAGE OR INJURY, FOLLOW THE WIRING DIAGRAM EXACTLY WHEN

CONNECTING A UNIT.
CAUTION: DO NOT USE PLASTIC PIPE. DRAIN MUST BE RATED FOR STEAM AND BOILING WATER.

WARNING: DO NOT CONNECT THE DRAIN DIRECTLY TO A BUILDING DRAIN.

WARNING: BLOCKING THE DRAIN MAY BE HAZARDOUS.

IMPORTANT: Improper drain connection will void warranty.

WARNING: ALLOW COOKING CHAMBERS TO COOL BEFORE CLEANING.

WARNING: CAREFULLY READ THE WARNINGS AND FOLLOW THE DIRECTIONS ON THE LABEL OF

EACH CLEANING AGENT. USE SAFETY GLASSES AND RUBBER GLOVES AS

RECOMMENDED BY DELIMING AGENT MANUFACTURER.

WARNING: DO NOT MIX DE-LIMING AGENTS (ACID) AND DE-GREASERS (ALKALI) IN THE STEAM

GENERATOR OR ON THE COOKING CHAMBER WALLS.

NOTICE: Do not use a cleaning or de-liming agent that contains any sulfamic acid or any chloride,

including hydrochloric acid (HCl). If the chloride content of any product is unclear,

consult the manufacturer.

NOTICE: Do not use a de-greaser that contains potassium hydroxide or sodium hydroxide or that is

highly alkaline.

WARNING: USE OF ANY REPLACEMENT PARTS OTHER THAN THOSE SUPPLIED BY GROEN OR

THEIR AUTHORIZED DISTRIBUTOR VOIDS ALL WARRANTIES AND CAN CAUSE BODILY

INJURY TO THE OPERATOR AND DAMAGE THE EQUIPMENT. SERVICE PERFORMED BY

OTHER THAN FACTORY-AUTHORIZED PERSONNEL WILL VOID ALL WARRANTIES.
WARNING: HIGH VOLTAGE EXISTS INSIDE CONTROL COMPARTMENTS. DISCONNECT FROM

BRANCH BEFORE SERVICING. FAILURE TO DO SO CAN RESULT IN SERIOUS INJURY

OR DEATH.

WARNING: DO NOT EXPOSE SKIN TO ESCAPING STEAM. SEVERE BURNS CAN RESULT.

2

OM-NGB/3

Table of Contents

OPERATOR WARNINGS ....................................................................2

EQUIPMENT DESCRIPTION .................................................................4

WATER CONDITIONING REQUIREMENTS .....................................................4

INSTALLATION INSTRUCTIONS ..............................................................5

INITIAL START-UP .........................................................................6

OPERATING INSTRUCTIONS ................................................................7

SEQUENCE OF OPERATION ................................................................ 8

CLEANING AND MAINTENANCE PROCEDURES

CLEANING .........................................................................9

MAINTENANCE ....................................................................11

TROUBLESHOOTING ...............................................................12

DIAGRAMS ..............................................................................15

SCHEMATICS ............................................................................18

REFERENCES ............................................................................ 20

SERVICE LOG ............................................................................21

NOTES ..................................................................................22

WARRANTY PROTECTION .................................................................23

3

OM-NGB/3

Equipment Description

Groen NGB/3 and NGB/3/E steam
boilers generate low pressure
steam for use with HyPlus cabinet­mounted steamers and steam
jacketed kettles. The models are
distinguished by their ignition
systems. The NGB/3 uses a
standing pilot and the NGB/3/E
uses a spark ignition system.

The boiler is housed in a stainless
steel cabinet. Various
combinations of steam-operated
kettles and steamers can be
mounted on the top. The boiler is
small enough to fit in a 24-1/8” wide by 34-3/16"
deep by 29-3/16" tall (maximum) cabinet.

Water Conditioning

It is essential that the boiler be supplied with water
that will not form scale at an unacceptable rate. The
boiler was engineered to minimize scale, but its
formation depends on water hardness and how
much the unit is used.

In some areas of the United States the water is low
enough in mineral content to avoid scale build-up.
However, most water supplies carry heavy loads of
minerals. This will form scale on the boiler, reduce
its steam output, and possibly cause premature
component failure.

Your water utility can tell you about the minerals in
your water. The water going to the steam generator
should have between 1 and 30 parts per million
total dissolved solids (TDS) and should have a pH
(acidity rating) of 7.0 or higher.

Please follow these simple precautions:

1. Do not rely on unproven water treatment

equipment which is sold for scale prevention or

scale removal. They frequently don’t work.
The best way to prevent scale is to supply the
purest possible water.

The boiler is constructed of 1/4" thick
steel, which is certified by the
American Society of Mechanical
Engineers (ASME) for pressure
vessels. All welds are hydrostatically
tested. The boiler is also equipped with
required instruments, fittings, and
controls.

Heat transfer fins inside the
combustion chamber add to the unit’s
high efficiency. The NGB/3 and
NGB/3E are both rated as 60%
efficient or better, with a firing rate of

200,000 BTU per hour using natural or
propane gas. Energy output is 120,000 BTU per
hour, with an effective boiler horsepower of 3.7.

generator life, higher steam capacity, and
reduce maintenance requirements.

4. If you notice a slowdown in steam production,

check the boiler for scale build-up. Heavy scale
reduces the unit’s ability to boil water, and can
even cause heating elements in the steam
generator to overheat and burn out.

5. Groen gas and electric pressure boilers are

available with two separate water intakes:
one for the boiler (soft water)

one for the spray condenser (untreated water).
The steam generator only uses 14 to 31% of a

steamer’s water. Since softener systems are
typically sized by total GPH (gallons per hour),
the second intake could reduce treatment
requirements by up to 80%, resulting in
significant savings.

Reduce scale problems by using and
maintaining a water softener for your
steamer !

2. If your water contains scale-forming minerals,
as most water does, use a well-maintained
water softener. Whether an exchangeable
softener cartridge or a regenerating system is
chosen, a regular exchange system is essential.

3. Installing a water meter between the softener
and the steamer will provide an accurate gauge
of water use, and will help determine when to
exchange cartridges or regenerate the softener.
Using a water softener will provide longer

4

OM-NGB/3

Installation

WARNING
THE UNIT MUST BE INSTALLED BY PERSONNEL WHO ARE QUALIFIED TO WORK WITH
GAS, ELECTRICITY AND PLUMBING. IMPROPER INSTALLATION CAN CAUSE INJURY
TO PERSONNEL AND/OR DAMAGE TO THE EQUIPMENT. THE UNIT MUST BE
INSTALLED IN ACCORDANCE WITH APPLICABLE CODES.

Getting Started

WHEN THE UNIT IS RECEIVED, IMMEDIATELY
INSPECT IT FOR EXTERNAL OR INTERNAL
DAMAGE. REPORT ANY DAMAGE TO THE
FREIGHT CARRIER.

After inspection, keep the unit in its shipping
container until it is installed. It can be installed on
combustible and non-combustible floors. Minimum
clearances are:

Right Side — Two inches
Left Side — Four inches
Rear — Six inches

In order to service the unit properly, access with
at least 24 inches clearance is needed on the
right side.

Install the unit in a well-vented room so that there is
an adequate air supply. Since products of
combustion come out of its flue, the appliance must
be located under a ventilation hood. Do not

directly vent the flue.

Level the unit front to rear and left to right by
adjusting its legs. Levelness may be checked by
using a spirit level on top of the cabinet.

A free flow of air around the boiler promotes
efficient operation. Items which might restrict air
flow must be removed. After installation, do not
obstruct the flue, or any front, side, rear or top
vents. Similarly, keep the area directly around the
appliance clear of combustible material.

Installation must conform with local codes, or in the
absence of local codes, with the National Fuel Gas
Code, ANSI Z223.1 (latest edition, including the
following paragraph:

“The unit and its individual shut-off valve must
be disconnected from the gas supply piping
system during any pressure testing of that
system at test pressures in excess of ½ PSI
(3.45 kPA). The unit must be isolated from the
gas piping system by closing its individual
manual shut-off valve during any pressure
testing of the gas supply piping system at test
pressures equal to or less than ½ PSI
(3.45kPA).”

CAUTION

MAKING ANY ELECTRICAL OR MECHANICAL
CHANGE IN THE UNIT WITHOUT PRIOR
GROEN APPROVAL WILL VOID ALL
WARRANTIES.

1. Gas Supply Connection

a. Connection to the gas supply can be completed

with 1/2" NPT pipe or approved equivalent.
Although this is the diameter for immediate
connection to the unit, gas supply piping must

be large enough to provide volumes and
pressure sufficient for 200,000 BTU per hour.

Supply pressure must be at least 5.0" W.C.
(14.0" W.C. maximum) for natural gas or 11.0
W.C. (14.0" W.C. maximum) for propane.

b. In Canada, the installation must conform to the

Canada Gas Code, CAN 1-B149 (Installation

Codes for Gas Burning Appliances and
Equipment), and/or local codes.

c. After the unit has been connected to the gas

supply, check piping joints for leaks. Do NOT
use flame to check for leaks. A thick soap
solution or other suitable leak detector should be
used.

2. Electrical Supply Connection

a. The maximum electrical load is 4 AMP. You

must provide 115 Volt Alternating Current, 60
Hz, 1PH, 15 AMP service. Local codes and/or
the National Electrical Code should be followed
(ANSI/NFPA-70-1987 - or latest edition). AN

ELECTRICAL GROUND IS REQUIRED.

b. Copies of the electrical schematic are located in

the electrical enclosure on the equipment and in
this manual. In Canada, electrical service must
comply with the Canadian Electrical Code, CSA
C22.1, Part 1, and/or local codes.

3. Water Connection

a. Cold water is supplied via a 1/2" NPT pipe

connection at the rear of the unit. A check

5

OM-NGB/3

valve (back siphonage device) must be installed
in accord with local plumbing codes.

b. Water pressure should be between 30 and 60

PSI. If it is over 60 PSI, a pressure regulator is
required. A strainer screen at the connection is
also recommended, to trap any debris before it
can enter the system.

c. The NGB/3 boiler uses a maximum of 12.9

gallons of water per hour. Piping should be
sized to handle total water consumption.

4. Drain Connection

a. The drain connection is made at the rear of the

unit with 1 - 1/4" NPT pipe. DO NOT USE
PLASTIC PIPE. DRAIN PIPING MUST
WITHSTAND STEAM AND BOILING WATER.
Extend the drain piping to a nearby floor drain.
Piping of 1 - 1/4" NPT (or 1 - 1/2" NPT) is
acceptable for distances of six feet or less. If
the distance to the drain is further than six feet,
use 2" NPT piping.

b. The drain line must be installed with a constant

downward pitch. Do not permit any water traps
in the line. DO NOT CONNECT THE LINE
DIRECTLY TO ANY BUILDING DRAIN. A
vertical air gap of at least two inches must be
maintained between the drain line and the
building drain unless otherwise specified by
local plumbing codes.

CAUTION
DO NOT LOCATE THE BOILER CABINET
DIRECTLY OVER A FLOOR DRAIN OR FLOOR
SINK. HUMIDITY OR WATER FROM WILL
DAMAGE ELECTRICAL.

Leave a two-inch air gap between the hose and
the building drain, and don’t allow water traps
in the line.

IMPORTANT: Improper drain connection will
void warranty.

6

Initial Start-Up

After the unit has been installed, test it to ensure
that it is operating properly.

OM-NGB/3

When the water level reaches the “mid” probe,
the red RESET light will come on. Push the start
switch.

1. Remove literature and packing material from the
interior and exterior of the unit.

2. Make certain the water supply is turned on.

3. Turn on electrical power to the unit.

4. Make sure the gas supply line is open, and turn
on the gas valve.

a. For NGB/3: Turn the knob on the gas valve to

“PILOT,” then push the knob inward and hold,
while lighting the pilot burner. Continue to
hold the knob in for about 60 seconds after
the pilot burner lights, so that the
thermocouple energizes, and the pilot stays
lit. Release the knob and turn it to the “ON”
position.

b. For NGB/3/E: Turn the knob on the gas valve

to the “ON” position.
NOTE: On NGB/3/E, the “trial for ignition”

period is approximately 90 seconds after the
on/off switch is turned to the “ON” position.
(Refer to the Control Panel illustration in the
Operation Section).

• The green light in the switch will come on

• The RESET light will go out

• The main burner will light
When the water level reaches the “hi” probe, the

water supply to the boiler will shut off.

6. After about 15 minutes, the pressure on the
gauge will rise. When the pressure reaches 9­1/2 PSI, the main burner will turn off. Thereafter,
as pressure decreases, the burner will
automatically re-light to maintain the 9-1/2 PSI
level. The pilot burner should stay lit, even
though the main burner cycles on and off.

7. To shut the unit down, turn the on/off switch to
OFF. When it has cooled to approximately
170oF, the unit will automatically drain.

If desired, the pilot burner may also be turned off
at the gas valve on the NGB/3 (standing pilot), to
conserve energy during idle periods.

On the NGB/3/E (spark ignition)boiler, the pilot is
off when the on/off switch is OFF.

During initial start-up several trials may be
necessary to remove air from the gas piping.
Subsequent start-ups should only need about
five seconds for the pilot to light. If the pilot
burner does not light within the trial period, the
ignition system will automatically stop gas
flow to the pilot burner, and terminate the
ignition trial. If this happens, turn the switch
to “OFF” and then “ON” again, to repeat the
trial for ignition.

5. Turn the on/off switch on the cabinet front panel
to the “ON” position:

• The amber light in the switch will come on

• The boiler drain valve will close

• The unit will fill with water

If the unit functions as described above, it is ready
for use. If it does not, contact your authorized
Groen Service Agent..

Operating Controls are located on the front of the cabinet base unit.

7

OM-NGB/3

Operation

WARNING
ALL POTENTIAL USERS OF THE EQUIPMENT MUST BE TRAINED IN SAFE AND CORRECT
OPERATING PROCEDURES

1. Controls

Operating controls are located on the front panel of
the unit.

a. The on/off switch starts the unit or shuts it off.
b. The RESET indicator lights to show that the

boiler has filled with water and that the main
burners can ignite.

c. The start switch (momentary) lights the main

burners. It also restarts the unit if electrical
power is interrupted, or if a low water
condition in the boiler disables the unit.

In addition to operating these controls, there are gas
supply controls located on the gas valve.

a. For NGB/3: The control knob is turned to the

“PILOT” position and held down to light the
pilot burner. If the pilot remains lit when the
control knob is released, the knob may be
turned to the “ON” position. This lets gas flow
to the main burners. When the knob is turned
“OFF,” gas flow stops to both the pilot and
main burners.

b. For NGB/3/E: When the control knob is “ON,”

gas flows to the pilot, as well as to the main
burners.

2. Operating Procedure

a. Turn on the water supply to the unit.
b. Turn on electrical power to the unit.
c. Turn on the gas supply to the unit, and turn on

the gas valve.

1) For NGB/3: Turn the gas valve control
knob to the “PILOT” position. Depress the
knob and light the pilot burner. Keep the
knob depressed for about 60 seconds
after the pilot lights, to allow the
thermocouple (which controls gas flow to
both the burners and the pilot) to heat up.
When the knob is released, the pilot
burner will remain lit. Turn the control to
the “ON” position.

2) For the NGB/3/E: Turn the control knob
on the gas valve to the “ON” position.

terminate the ignition trial. If ignition is
terminated, turn the switch off and then
“ON” again to repeat the trial. Normally,
the pilot should light within five seconds of
turning on the unit.

d. Turn the on/off switch on the front of the

cabinet to “ON.”

1) The amber light will come on.

2) The boiler drain valve will close and the
unit will fill with water.

3) When the water reaches the “mid” probe,
the red RESET light will come on.

4) Press the start switch.

5) The green light in the switch will come on,
the RESET light will go off, and the main
burner will light.

6) When the water level reaches the “hi”
probe, the water supply to the boiler will
shut off.

e. After about 15 minutes, the pressure gauge

will indicate that the pressure is rising. When
it reaches 9-1/2 PSI, the main burner will shut
off. Thereafter, the burner will periodically re­light to maintain the pressure at 9-1/2 PSI.
The pilot light should stay lit when the burner
is off.

f. To shut down the unit, turn the on/off switch to

OFF. The unit will drain automatically after it
has cooled to about 170oF. When the NGB/3
(standing pilot) unit will be idle for extended
periods, the pilot burner may be turned off at
the gas valve to conserve energy. The
NGB/3/E (spark ignition) turns off the pilot
light when the on/off switch is turned to OFF.

NOTE On the NGB/3/E the “ignition trial” period

runs for approximately 90 seconds after
the on/off switch is turned ON. This
means that if the pilot light does not light
within the “trial” period, the ignition system
will automatically stop the gas flow and

8

Sequence of Operation

OM-NGB/3

When electrical power is turned on to the unit, the
following happens:

• The drain valve closes

• The water valve opens

• The unit fills with water

As the boiler fills, the water is detected by two
probes. The first of these is the “mid” probe, which
activates the RESET light. The second (“hi” probe)
is reached when the boiler is full, and shuts off the
water supply. As the water supply drops below this
probe, the water supply opens until it is again
reached.

The gas valve has a step-opening feature. When
the control calls for the main burner to light, the
outlet pressure of the valve is maintained at a
preset (non-adjustable) rate for several seconds,
before full rated pressure is allowed to develop.

Once the main burner shuts down, step-opening gas
valves need at least 60 seconds to reset. If an
attempt to re-light the burner is made before these
valves reset, it may bypass or shorten the length of
the low pressure step, and could re-light the main
burner under full flow rate.

problem which caused the shut-down has been
corrected.
As an additional safety measure, the unit is
equipped with an A.S.M.E.-certified safety valve
which will open to relieve excess pressure at 15
PSI. The ability of this valve to discharge steam
pressure is greater than the boiler’s ability to
generate steam.

When electrical power is turned off, the gas valve
automatically shuts off flow to the main gas burner.

A thermostatic switch (mounted on the boiler shell)
keeps the drain valve closed until the temperature
drops to approximately 170oF.

At that point, the thermostatic switch opens and
water drains from the boiler. A vacuum breaker
allows air to enter the boiler for this purpose.

CAUTION

WAIT AT LEAST 60 SECONDS BEFORE
ATTEMPTING TO RE-LIGHT THE MAIN
BURNER AFTER IT SHUTS OFF.

A thermostatically-controlled air vent remains open
while the boiler fills. As steam begins to develop,
this vent will close. Some steam may escape from
this vent before it is fully closed (at approximately
200oF).

Once the pressure has reached 9-1/2 PSI, the main
burner will be shut off by an operating pressure
switch. Residual heat stored in the boiler’s heat
exchanger can, however, cause the pressure to
continue to build, even after the burner has shut
down. This is especially true when the unit is
heated for the first time.

If/when the pressure reaches 12 PSI, a relief valve
will open to prevent pressure from increasing past
12 PSI. As pressure decreases, the main burner will
automatically re-light to maintain 9-1/2 PSI.

Even if something causes the pressure to pass
12PSI, a high-limit safety switch will shut down the
boiler electrically when it reaches 14-1/2 PSI. If this
happens, the unit should not be re-started until the

9

OM-NGB/3

Cleaning

Whenever the boiler is turned off and allowed to
cool to about 170 oF, it drains automatically. This
should be done every day to minimize scale build­up inside the boiler.

In addition to this draining, however, the following
cleaning procedure should be followed using a
regular schedule. This will prevent the
accumulation of lime on the water level probes and
interior surfaces of the boiler. The actual time
between these scheduled cleanings depends on the
water quality and hours of operation. Minimally,
Groen recommends cleaning the boiler at least once
each month.

A. Suggested Tools

1. 1/2" hardened square wrench extension

2. Pipe Joint compound
3 32 oz. Groen Delimer Descaler (PN 114800),

Lime-A-Way or equivalent

4. Groen Spray Degreaser (PN 114801, or
equivalent

5. Nylon pad(s)

B. Procedure

WARNING
WATER AND VALVES MAY BE VERY HOT,
AND MAY CAUSE BURNS. PROTECT HANDS
FROM HOT SURFACES AND WATER.

1. Turn the boiler on/off switch to the OFF position.

2. Slowly open the manual drain valve to empty
the boiler. The valve is located under the boiler.

3. Close the manual drain valve.

4. Turn off water supply to the boiler.

5. Allow the boiler to cool. This takes several
hours, so it is recommended that you cool the
boiler overnight.

6. Turn on/off switch to “ON” to close the
automatic drain valve.

7. Using a 1/2" hardened square wrench extension,
remove one of the 1" NPT pipe plugs from the
front of the boiler.

The manual drain valve is located under the
boiler.

10

OM-NGB/3

16. Completely wipe out steamer chambers using a
degreaser and nylon pad, if necessary. Rinse
thoroughly with clean water.

17. Replace fan baffle partitions.

USE SAFETY GLASSES AND RUBBER

WARNING

GLOVES AS RECOMMENDED BY DE-LIMING
AGENT MANUFACTURER.

8. Pour 32 ounces of de-limer (Groen Delimer
Descaler - Part Number 114800), Lime-a-Way®
or equivalent) into the boiler.

CAUTION

DO NOT USE A CLEANING OR DE-LIMING
AGENT THAT CONTAINS SULFAMIC ACID OR
ANY CHLORIDES, INCLUDING
HYDROCHLORIC ACID (HCL). IF THE
CHLORIDE CONTENT OF ANY PRODUCT IS
UNCLEAR, CONSULT THE MANUFACTURER.

9. Replace the pipe plug. Use pipe joint
compound, and tighten the plug securely.

10. Turn on water supply to allow water to fill the
boiler.

11. When the reset light appears, press the START
switch.

18. Wait 10 minutes for the compartments to air
dry, then close the steamer doors.

19. Turn the on/off switch OFF, and slowly open the
manual drain valve.

WARNING
SOLUTION AND VALVES WILL BE VERY HOT,
AND MAY CAUSE BURNS. PROTECT HANDS
FROM HOT SURFACES AND CONTINUE TO
USE PROTECTIVE GLOVES.

20. When the boiler has drained completely, close
the manual drain valve and turn the on/off
switch to “ON” to fill the boiler with water.

21. After the RESET light comes on, press the start
switch.

22. Allow boiler pressure to develop

12. Allow boiler pressure to develop. Let it stand for
approximately 15 minutes after pressure has
built up. A badly limed unit may require more
than 15 minutes.

If there are no steamer cavities or compartments
with this boiler, proceed to step 19.

13. Set steamer timers for 10 minutes.

14. When steamer timers sound, turn them to OFF
and open the doors.

15. When the fans have stopped, remove fan baffle
partitions using protective gloves, and rinse
with clean water.

If steamers are not present, proceed to step 25.

23. Set steamer timers for 10 minutes.

24. When steamer signal sounds, turn timers off.

25. If the boiler is not to be used, it may be turned
off. It is ready for normal operation.

11

Maintenance

Your Groen boiler is designed to minimize
maintenance, but certain parts may need to be
replaced after prolonged use. For the most part, no
user adjustments should be necessary. If a need for
service arises, only Groen personnel or Authorized
Groen Representatives should perform the work.

Among the most common problems is the rapid
build-up of scale in the boiler. To avoid this, always
supply water that has a low mineral content,
which meets the standards described in the Water

Conditioning section of this manual.

WARNING
USE ONLY GROEN-SUPPLIED PARTS.
USING SUBSTITUTE, UNAUTHORIZED OR
“GENERIC” PARTS CAN CAUSE BODILY
INJURY TO THE OPERATOR AND DAMAGE
THE EQUIPMENT.

Periodic Inspection

WARNING
DO NOT EXPOSE SKIN TO ESCAPING STEAM.
SEVERE BURNS MAY RESULT.

The unit should be inspectedby a qualified service
technician at least once each year. The inspection
should include electrical wires and connections,
cleaning the inside of the control enclosure and pilot
burner adjustment, if required.

At the back of this manual (with the information
about our warranty) is a Maintenance and Service
Log. Each time maintenance is performed on the
unit, enter the date on which it was done, what was
done, and who did it. Keep this log with the
warranty.

In addition to yearly inspections by a qualified
service technician, a weekly check of the following
will help prevent down time and ensure continued
efficient operation.

1. Pressure gauge operation

2. Proper water level (gauge)

3. Strainer in water feed line (clear?)

4. Air inlets for gas burner jets (clean?)

5. Pilot burner flame (blue? Envelops sensor?)

6. Drain piping (free running? No blockage?)
At least twice each month, check the safety valve to

be sure it is working properly. When pressure
reaches five PSI on the gauge, lift the lever to vent
steam, then release it, allowing it to snap back into
place.

The safety valve is located on the top
left rear of the boiler.

Component Replacement

NGB/3 and NGB/3/E boilers are easy to service.
The design is simple, and controls are readily
accessible.

Before replacing any part, COMPLETELY SHUT

OFF THE GAS AND ELECTRICAL POWER TO
THE UNIT. When breaking (opening) a gas pipe

connection, allow five minutes for gas to dissipate
before proceeding.

When the pipes have been reconnected, check for
leaks with a thick soap solution or other suitable leak
detector. Do not use flame to check for gas

leaks.

12

OM-NGB/3

Troubleshooting

Do not operate the unit if it malfunctions or has damaged or broken parts.

NGB/3 and NGB/3/E steam boilers are designed to operate smoothly and efficiently when maintained properly.
However, the following is a list of checks to make if there is a problem. Electrical schematics are provided in this
manual, and inside the unit electrical enclosure. IF THE ITEM ON THE LIST IS MARKED WITH (X), THE

WORK SHOULD ONLY BE DONE BY A FACTORY-AUTHORIZED SERVICE REPRESENTATIVE.

SYMPTOM WHO WHAT TO CHECK

Items marked with (X) should only be done by a factory-authorized service rep.

Boiler does not fill with water User can

check

Auth
Service
Rep Only

Boiler overfills with water User can

check
Auth

Service
Rep Only

Boiler underfills with water User can

check

Water enters boiler slowly. User can

check

Auth
Service
Rep Only

RESET light does not comeonAuth

Service
Rep Only

Pilot burner will not light
(standing pilot)

User can
check

Auth
Service
Rep Only

a. Is water supply connected and is water present?
b. Is water pressure low (less than 30 PSI)?
c. Is strainer screen (if used) clogged?
d. Is on/off switch in base cabinet turned on? Is the amber light in

the on/off switch “ON”?

e. Is the manual drain valve open?
f. Is the Water Level Control Board (PCB) defective? Check for

loose electrical connections on water fill solenoid. (X)
g. Is the water fill solenoid valve defective? (X)
h. Is the solenoid drain valve open or leaking? Check for loose

electrical connections on solenoid drain valve. (X)
a. Is the boiler level? Check levelness of unit with a spirit level.

b. Is the water pressure too high? (Greater than 60 PSI?)
c. Is the Water Level Control Board (PCB) defective? Check for

loose electrical connections on “hi” water fill solenoid. (X)
d. Is the water fill solenoid valve defective? (X) Check for debris

on valve seat.
e. Is the “hi” water probe sensing level? Clean water level probe

and probe well (located in boiler). (X)
a. Is the boiler level? Check levelness of unit with a spirit level.

a. Is strainer screen (if used) clogged?
b. Is the water pressure too low? (Less than 30 PSI)?
c. Is the water supply line too small?

d. Is the water fill solenoid defective? (X)

a. Is the Is the Water Level Control Board (PCB) defective?

Check for loose electrical connections on “mid” water fill

solenoid. (X)
b. Is the “mid” water probe sensing level? Clean water level

probe and probe well (located in boiler). (X)
c. Is the indicator light defective? (X)

a. Is supply gas valve open?
b. Is gas valve in “pilot” position and knob depressed when

lighting the pilot?
c. Does the pilot flame require adjustment? Screw attachment on

gas valve (X)
d. Is the gas valve defective? (X)

13

OM-NGB/3

SYMPTOM WHO WHAT TO CHECK

Pilot burner will not light
(spark ignition)

Pilot burner will not stay lit
(standing pilot and spark
ignition)

Main burner will not light
(standing pilot)

Main burner will not light
(spark ignition)

Boiler does not build
pressure with main burner lit.

Main burner does not shut off
after reaching operating
pressure.

Boiler builds pressure but
shuts down. RESET light
comes on.

Safety relief valve opens. Auth

User can
check

Auth
Service
Rep Only

Auth
Service
Rep Only

User can
check

Auth
Service
Rep Only

User can
check

Auth
Service
Rep Only

User can
check

Auth
Service
Rep Only

User can
check

Auth
Service
Rep Only

User can
check

Auth
Service
Rep Only

Service
Rep Only

Items marked with (X) should only be done by a factory-authorized service rep.

a. Is supply gas valve open?
b. Is gas valve knob in the “ON” position?
c. Is the boiler filled with water? Is the green light in the start

switch “ON”?
d. Does the pilot flame require adjustment? Screw attachment on

gas valve (X)
e. Is the gas valve defective? (X)

a. Does the pilot flame require adjustment? Screw attachment on

gas valve (X)

a. Is pilot burner lit?
b. Is gas valve knob in the “ON” position?
c. Is the boiler filled with water? Is the green light in the start

switch “ON”?
d. Is the thermocouple defective (X)

e. Is the gas valve defective (X)

a. Is pilot burner lit?
b. Is the boiler filled with water? Is the green light in the start

switch “ON”?
c. Is the igniter-sensor defective? (X)

d. Is the gas valve defective (X)
e. Is the spark ignition module defective? (X)

a. Is the steam power take-off valve open or leaking?
b. Is the pressure gauge defective?

c. Is the air vent leaking steam? (X)
d. Is the solenoid or manual drain valve open or leaking? NOTE:

Excessive make-up water added to the boiler reduces steam

production. (X)
e. Is the burner BTU output low? Check the gas pressure at the

burner. Adjust at the gas valve, if necessary. (X)
a. Is the pressure gauge defective?

b. Is the gas valve defective?
c. Is the operating pressure switch defective? No adjustment is

allowed. Replace the switch if defective. (X)

a. Is the water level below the “mid” water level probe? Verify

that the water supply is sufficient to maintain the water level at

or above the “mid” water level probe.
b. Is the operating pressure switch defective? No adjustment is

allowed. Replace the switch if defective. NOTE: If the high-

limit pressure switch has shut down the unit, it should not be

restarted until the problem which caused the shut-down has

been corrected. (X)
c. Is the “mid” water level probe unable to detect water? Clean

the water level probe and probe well (located in the boiler). (X)
a. Are the operating pressure switch and/or high-limit pressure

switch defective? No adjustment is allowed. Replace defective

switches. (X)
b. Is the safety relief valve defective? Replace with ASME-

approved 15 PSI valve with “HV” marking. (X)

14

Troubleshooting (Continued)

SYMPTOM WHO WHAT TO CHECK

Boiler blows down
immediately when turned off.

Boiler does not drain. User can

Auth
Service
Rep Only

check

OM-NGB/3

Items marked with (X) should only be done by a factory-authorized service rep.

a. Is the thermostatic switch defective? Check for loose electrical

connections on switch. (X)

a. Is the thermostatic switch defective?
b. Is the solenoid drain valve defective?
c. Are the solenoid drain valve or hoses blocked?

15

OM-NGB/3

Parts List

NGB/3 Burner and Gas Valve

NATURAL GAS GAS PROPANE GAS

Key Description Part No. Key Description Part No.

1 Baffle Plate 083076 1 Baffle Plate 083076
2 Pilot Burner Mounting Bracket 102215 2 Pilot Burner Mounting Bracket 102215
3 Pilot Burner (Standing Pilot) 102249 3 Pilot Burner (Standing Pilot) 102250
4 Shield for Pilot Burner 102252 4 Shield for Pilot Burner 102252
5 Flame Deflector (Single Loop) 056965 5 Flame Deflector (Double Loop) 056966
6 Thermocouple (For Standing Pilot Only) 076423 6 Thermocouple 076423

7a Main Burner Assy 0-2500 Ft. Elev.(Incl. (29) Gas Jets

W/ #54 Drill Dia Hole)

7b Main Burner Assy 2501-5500 Ft. Elev. (Incl.(29)Gas

Jets w/#55 Drill Dia Hole)

7c Main Burner Assy 5501-8500 Ft. Elev. (Incl.(29)Gas

Jets w/#55 Drill Dia Hole)

8 Gas Valve (Standing Pilot) 077973 8 Gas Valve (Standing Pilot) 082908

For Spark Ignition (Natural Gas) For Spark Ignition (Propane Gas)

2 Pilot Burner Mounting Bracket 102257 2 Pilot Burner Mounting Bracket 102257
3 Pilot Burner W/ Spark Igniter-sensor 102258 3 Pilot Burner W/ Spark Igniter-sensor 104392
4 Shield for Pilot Burner 102260 4 Shield for Pilot Burner 102260
8 Gas Valve (Spark Ignition) 101497 8 Gas Valve (Spark Ignition) 104391
9 Spark Ignition Module (Used with Gas Valve P/n

101497)

10 Ignition Cable 085154 10 Ignition Cable 085154

-- Kit, Conversion-standing Pilot to Spark Ignition 102295

047267 7a Main Burner Assy 0-2500 Ft. Elev. (Incl (29) Gas

Jets w/ #68 Drill Dia Hole)

065949 7b Main Burner Assy 2501-5500 Ft. Elev. (Incl(29)

Gas Jets w/ #69 Drill Dia Hole)

091938 7c Main Burner Assy 5501-7500 Ft. Elev. (Incl(29)

Gas Jets w/ #70 Drill Dia Hole)

085153 9 Spark Ignition Module (Used with Gas Valve P/n

104391)

050491

065019

065478

085153

16

Parts List

NGB/3 Boiler

OM-NGB/3

Key Description Part No. Key Description Part No.

1 Boiler Weldment MS98221 10 Air Vent 084098
2 Sight Glass Assembly 071534 11 Vacuum Breaker 090787
3 Kit, Repair - Sight Glass 097099 12 Globe Valve 1/2"NPT 099255
4 Flue 099217 13 Operating Pressure Switch-9½ PSI 099222
5 Safety Valve (15PSI) 102297 14 Hi-limit Pressure Switch-14½ PSI 099223
6 Pressure Relief Valve (12PSI) 099228 15 Pressure Gauge 078000
7 Water Level Probes (lo, med, hi) 076526 16 Solenoid Valve (Drain) 074594
8 Solenoid Valve (Water-in) 099220 17 Ball Valve (3/4" NPT) 009883
9 Check Valve 004187 18 Thermostatic Switch 077985

17

OM-NGB/3

Parts List

NGB/3 Electrical Controls

Key Description Part No. Key Description Part No.

1 Switch "On/off" 088876 10 Fuse, 15 AMP (250VAC) 087946
2 Switch "Start" (Momentary) 099290 11 Relay 24VAC Coil 074842
3 Indicator Light "Reset" 099289 12 Transformer 120/208/240V Pri-24V

4 Circuit Board Supports (1/2" High) 099292 13 Fuse, 7 AMP 096798
5 Liquid Level Control Board 099246 14 Terminal Block 2-Pole 003887
6 Circuit Board Supports (1/4" High) 102228 15 Ground Lug 002863
7 Fuse Board 102220 16 Tie Anchor 102231
8 Fuse, 3 Amp (Fast-blow) 077853 17 Wire Harness (Not Shown) 102212
9 Fuse Holder 077854

094164

Sec.

18

Electrical Schematic

NGB/3 (Standing Pilot)

OM-NGB/3

19

OM-NGB/3

Electrical Schematic

NGB/3/E (Spark Ignition)

20

References

AMERICAN GAS ASSOCIATION LABORATORIES
8501 East Pleasant Valley Road
Cleveland, Ohio 44131

AMERICAN NATIONAL STANDARDS INSTITUTE
1403 Broadway
New York, New York 10018

Z21.30 Installation of Gas Appliances and Gas Piping
Z223.1 (latest edition) National Flue Gas Code

NATIONAL FIRE PROTECTION ASSOCIATION
60 Battery March park
Quincy, Massachusetts 02269

NFPA/54 Installation of Gas Appliances and Gas Piping
NFPA/70 The National Electrical Code
NFP/96 Ventilating Hoods

OM-NGB/3

21

OM-NGB/3

Service Log

Model No.
Serial No.
Date Purchased

Purchase Order No.

Date Maintenance Performed Performed by

Purchased From
Location

Date Installed

For Service Call

22

OM-NGB/3

LIMITED WARRANTY TO
COMMERCIAL PURCHASERS*

(Continental U.S., Hawaii and Canadian Sales Only)

Groen Foodservice Equipment (“Groen Equipment”) has been skillfully manufactured, carefully inspected,
and packaged to meet rigid standards of excellence. Groen warrants its Equipment to be free from defects
in material and workmanship for (12) twelve months, with the following conditions and subject to the following
limitations.

This parts and labor warranty is limited to Groen Equipment sold to the original commercial
purchaser/users (but not original equipment manufacturers {O.E.M.}), at its original place of installation in
the continental United States, Hawaii and Canada.

Damage during shipment is to be reported to the carrier, is not covered under this warranty, and is the
sole responsibility of the purchaser/user.

Groen, or an authorized service representative, will repair or replace, at Groen’s sole election, any Groen
equipment, including but not limited to, drawoff valves, safety valves, gas and electric components,
found to be defective during the warranty period. As to warranty service in the territory described above,
Groen will absorb labor and portal to portal transportation costs (time and mileage) for the first twelve
(12) months from date of installation or fifteen (15) months from date of shipment from Groen.

This warranty does not cover boiler maintenance, calibration, periodic adjustments as specified in
operating instructions or manuals, and consumable parts such as scraper blades, gaskets, packings, etc.,
or labor costs incurred for removal of adjacent equipment or objects to gain access to Groen Equipment.
This warranty does not cover defects caused by improper installation, abuse, careless operation, or
improper maintenance of equipment. This warranty does not cover damage caused by poor water
quality or improper boiler maintenance.

THIS WARRANTY IS EXCLUSIVE AND IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESS OR
IMPLIED, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE, EACH OF WHICH IS HEREBY EXPRESSLY DISCLAIMED. THE
REMEDIES DESCRIBED ABOVE ARE EXCLUSIVE AND IN NO EVENT SHALL GROEN BE LIABLE
FOR SPECIAL, CONSEQUENTIAL OR INCIDENTAL DAMAGES FOR THE BREACH OR DELAY IN
PERFORMANCE OF THIS WARRANTY.

Groen Equipment is for commercial use only. If sold as a component of another (O.E.M.) Manufacturer’s
equipment, or if used as a consumer product, such Equipment is sold AS IS and without any warranty.

*(Covers all Foodservice Equipment Ordered after October 1, 1995)

23

1055 Mendell Davis Drice
Jackson, MS 39272
Telephone [phone]

OM-NGB/3 (Revised 12/97)

Part Number 121003