Grieve Furnaces Installation & Operation Manual

GENERAL INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS

FOR FURNACES

TABLE OF CONTENTS
1 SHIPPING DAMAGE & HANDLING
2 PROPER FURNACE APPLICATION

2-1 General
2-2 Flammable Solvents
2-3 Combustible Material
2-4 Personnel Hazards
2-5 Maintenance and Inspection

3 INSTALLATION
3-1 Location
3-2 Building Considerations
3-3 Clearances
3-4 Ventilation
3-5 Exhaust Ductwork
3-6 Fuel Gas Supply
3-7 Electrical

4 PRIOR TO PLACING FURNACE IN SERVICE
5 PROCESSING
6 SAFETY EQUIPMENT
7 MAINTENANCE
8 TROUBLE SHOOTING
9 APPENDIX A - SAFETY EQUIPMENT, DESCRIPTION & OPERATION
10 APPENDIX B - REFERENCES
11 APPENDIX C - MINIMUM PERIODIC MAINTENANCE REPORT
12 APPENDIX D - SAFETY SHUT OFF VALVE LEAK TEST PROCEDURE
13 APPENDIX E - WARRANTY AND LIMITATIONS OF REMEDIES

Following these GENERAL INSTRUCTIONS in your manual are the following:

-OPERATING INSTRUCTIONS SPECIFIC FOR YOUR EQUIPMENT

-MECHANICAL PARTS LIST

-ELECTRICAL WIRING AND COMPONENT PARTS LIST

-LITERATURE AND INSTRUCTIONS ON COMPONENTS

These GENERAL INSTRUCTIONS have been written for many different types of furnaces,
therefore, some equipment or components referred to may not be present on your particular
piece of equipment.

After reading these GENERAL INSTRUCTIONS, also read the specific OPERATING

INSTRUCTIONS written for your equipment. An additional copy of the OPERATING
INSTRUCTIONS is provided in a plastic cover. Post these instructions at the furnace for the

operator to reference.

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1 SHIPPING DAMAGE AND HANDLING

DO NOT RETURN DAMAGED MERCHANDISE TO US.
FILE YOUR CLAIM AS OUTLINED BELOW

This merchandise has been thoroughly inspected and carefully packed before leaving our
plant. Responsibility for its safe delivery was assumed by the carrier at the time of shipment.
Claims for loss or damage to the contents must be made with the carrier, as follows:

1-1 VISIBLE LOSS OR DAMAGE
Any external evidence of loss or damage must be noted, at the time of delivery, on the freight

bill or express receipt and signed by the carrier's agent. Failure to adequately describe such
external evidence of loss or damage may result in the carrier refusing to honor a damage
claim. Make a written request for inspection by the carrier's agent within fifteen days of the
delivery date. Review the inspection report and do not sign it unless it adequately describes
the damage.

A claim must be filed with the carrier since such damage is the carrier's responsibility.
1-2 CONCEALED LOSS OR DAMAGE
Concealed loss or damage means loss or damage which does not become apparent until

the merchandise has been unpacked. The contents may be damaged in transit due to rough
handling even though the carton may not show external damage. When the damage is
discovered upon unpacking, contact the carrier and make a written request for inspection by
the carrier's agent within fifteen days of the delivery date. Review the inspection report and
do not sign it unless it adequately describes the damage.

A claim must be filed with the carrier since such damage is the carrier's responsibility. By
following these instructions carefully, we guarantee our full support of your claims to protect
you against loss from concealed damage.

1-3 RETURNING DAMAGED EQUIPMENT
Damaged equipment will not be accepted at our factory unless we have been advised and

instructions provided on how it should be returned. A copy of the freight claim must be
provided prior to returning the equipment.

1-4 HANDLING
After inspection, store and handle all equipment and components in their original crates until

ready for installation. Handle with care. The equipment may be heavy but some
components are of a delicate nature. If the equipment is to be stored, keep it in the original
crates and store in a location free from excessive dust, heat and moisture until ready for
installation.

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2 PROPER FURNACE APPLICATION

2-1 GENERAL

2-1.1 While furnaces are extremely versatile, they are usually purchased with a specific

application in mind. If your process has changed significantly or if you should have
reason to doubt that a specific application is a proper use of the equipment, consult
the factory before proceeding.

2-1.2 Explanatory Material (Annex A1.1) of the National Fire Protection Association

Publication 86 "Standard for Ovens and Furnaces" states; in part:
"Explosions and fires in fuel-fired and electric heat utilization equipment constitute a

loss potential in life, property and production.”
Most failures can be traced back to human error. The most significant failures

include inadequate training of operators, lack of proper maintenance, and improper
application of equipment."

2-1.3 To protect the furnace, furnace contents, property and personnel, a responsible

person should be in attendance during operation. Do not operate furnace
unattended. Special attention must be paid to:

-Setting correct temperature.

-Placing flammable solvents in a furnace not designed for that
purpose.

-Placing combustibles in a furnace that does not have adequate fire
protection.

-Allowing the product to remain in the furnace too long, thereby
encouraging combustion.

-Using a furnace for a process other than that for which it was designed.

2-1.4 Furnace operator should shut down the furnace immediately and notify their

supervisor if there are changes in furnace performance, a safety interlock trips or,
in the case of fuel fired equipment, the smell of natural gas or propane is present.
The furnace should not be put back into production until the causes are found and
corrected.

2.2 FLAMMABLE SOLVENTS

2-2.1 Processing solvents in a non-solvent furnace, exceeding the design temperature, or

exceeding the maximum amount of solvent allowed in a furnace, could result in fire
or explosion and bodily injury or property loss.

If flammable solvents or vapors will be present in a furnace, the Occupational
Safety & Health Administration (OSHA) requires that it have a separately powered
forced exhauster of adequate size and other related safety devices not supplied as
standard equipment. Furnaces designed for this purpose have a caution plate and
Furnace Design Data Form showing the maximum gallons of solvent, or pounds of
powder coating, and the maximum operating temperature for which that specific
furnace has been designed. If in doubt, consult factory for details.

2-2.2 It shall be the user's responsibility to ensure that the amount of flammable solvent

placed in the furnace and the operating temperature does not exceed the design
capacity -- see Safety Design Form and furnace caution nameplate.

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2-2.3 In areas outside of the furnace where flammable solvents are given off by material

prior to entering the furnace, provisions should be made to exhaust these vapors to
atmosphere to prevent them from being pulled into the furnace or collecting and
creating a flammable mixture.

2-3 COMBUSTIBLE MATERIAL

2-3.1 Introduction of combustible materials (such as paper, cardboard or wood) into the

furnace should be avoided because it might cause a fire. Do not use combustible
racks, trays, holders, spacers, etc. Periodically, clean all combustible material from
non-combustible racks, trays, holders, spacers, etc. If combustible products must
be processed in a furnace, extreme care must be taken to ensure that the operating
temperature does not exceed the ignition temperature of the product.

2-3.2 Furnaces containing or processing sufficient combustible materials (including

consideration for combustible drippings or deposits) to sustain a fire shall be
equipped with an automatic fire protection system including areas in exhaust ducts
that could accumulate combustible material. Fire protection systems should be
installed in accordance with the applicable National Fire Protection Guidelines:

-Sprinkler Systems in accordance with NFPA 13

-Water Spray Systems in accordance with NFPA 15

-Carbon Dioxide Extinguishing Systems in accordance with NFPA 12

-Foam Extinguishing Systems in accordance with NFPA 11

-Dry Chemical Extinguishing Systems in accordance with NFPA 17

-Water Mist Systems in accordance with NFPA 750
The extent of protection required will depend upon the construction and

arrangement of the furnace as well as the materials handled. Fixed protection,
such as automatic sprinklers or other types of fire extinguishing systems, should be
designed and installed by a qualified contractor.

2-3.3 Drip pans shall be provided to collect any combustible materials that may

accumulate beneath the product. A maintenance program must be developed to
remove any such accumulation before a substantial build-up occurs that could
spontaneously ignite and cause a fire. If you cannot acquire drip pans locally,
contact us for a quotation.

2-4 PERSONNEL HAZARDS

2-4.1 You must analyze your use of this equipment and determine if it creates a confined

space hazard, as defined by OSHA, in your work place. You are responsible for
posting appropriate warnings and complying with applicable OSHA STANDARDS
pertaining to confined space hazards. (Reference ANSI Z117-1 ASafety
Requirements for Confined Spaces@, see Appendix B)

2-4.2 If inert atmospheres are to be used, keep in mind that inert gases displace air and

create oxygen-deficient atmospheres. For this reason, they can cause suffocation.
Moreover, some inert gases, such as argon, are heavier than air and can collect in
low lying or sealed areas creating oxygen-deficient pockets within the work place.
Use inert atmospheres only in large work places with good ventilation. Do not
breathe in or enter an inert atmosphere piece of equipment until it has been
thoroughly purged with air.

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2-4.3 Heat processing equipment must always be used with caution. Proper equipment

such as insulated gloves, safety goggles and tongs should be used for reaching
into hot equipment. Proper supervision is essential and only trained personnel
should be allowed to operate the furnace.

Always remember you are working with elevated temperatures.

-Do not touch surfaces - they could be hot and burns could result.

-Do not breathe hot furnace air. Heated air could burn lungs.

-Many items become dangerous when heat is applied. Explosion or fire
could result. Make sure you know what you are putting in the furnace can
be heated safely at the furnace operating temperature.

2-4.4 Furnace heating elements operate at line voltage. Do not touch them or allow

work to come in contact with the heating elements. A door interlock is provided to
disconnect power from heating elements when the door is opened. Do not defeat
the operation of this door interlock.

2-5.5 Disconnect power before servicing equipment. Furnaces operate under high

voltage and electrical shock is possible. Proper panel lockout procedures should
be followed.

2-4.6 Disconnect other sources of potential energy such as compressed air, before

servicing. Proper lockout procedures should be followed.

2-4.7 Do not operate mechanical or electrical equipment with guards removed.

Operating with guards removed could result in bodily injury.

2-4.8 Furnaces with vertical lift doors or top loading doors must be blocked open before

passing beneath them. A falling door may cause bodily injury. A safety pin, latch or
support strut is provided for this purpose.

2-5 MAINTENANCE AND INSPECTION

2-5.1 Regularly scheduled inspection and maintenance of all safety devices shall be

performed by user. Failure to do this may result not only in fire or explosion
damage, but also contribute to accidental shutdowns and loss of production. See
Section 7 - Maintenance and Appendix C - Minimum Periodic Maintenance Report.

2-5.2 Regularly scheduled inspection of the furnace interior, heat chamber and ductwork

shall be performed by user to determine need for cleaning and repair. Failure to do
this may result in internal fires or component failure resulting in furnace damage
and loss of production.

2-5.3 It shall be the sole responsibility of the user to establish, schedule and enforce the

frequency of and the extent of the inspection/maintenance program (as well as the
corrective action to be taken) because only the user can know what the actual
operating conditions are. Contact your insurance authority, Factory Mutual or the
National Fire Protection Association, whose addresses are listed in Appendix B, for
more information on inspection/maintenance programs.

2-5.4 It shall be the responsibility of the end user to determine that current processing is

within the scope of the original design of the equipment.

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2-6 RETROACTIVITY

This equipment has been designed and manufactured in accordance with applicable
National Codes in effect as of the date of manufacture. It is the responsibility of the end user
to update equipment as necessary to comply with future code changes. If you are in doubt,
contact manufacturer to review your equipment design against current National Codes.

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3 INSTALLATION

3-1 LOCATION

3-1.1 Furnaces shall be located to protect them from damage by external heat, vibration

and mechanical hazards.
3-1.2 Furnaces shall be located to make maximum use of natural ventilation, to minimize

restrictions to adequate explosion relief, and to provide sufficient air supply for
personnel. Room volume should be at least 10 times the furnace volume.

3-1.3 Furnaces shall be located to minimize exposure to power equipment, process

equipment and sprinkler risers. Unrelated stock and combustible materials shall be
maintained at a fire-safe distance but not less than 10 feet from a furnace, a
furnace heater or ductwork.

3-1.4 Furnaces shall be located to minimize exposure to people from the possibility of injury

from fire, explosion, asphyxiation, and hazardous materials and shall not obstruct
personnel travel to exit ways.

3-1.5 If the furnace control panel is located away from the furnace, operators must be

allowed access to the control panel and/or main disconnect to allow them to shut
down the furnace in an emergency.

3-1.6 Furnaces shall be located to prevent an ignition source to flammable coating dip

tanks, spray booths and storage and mixing rooms for flammable liquids and to
prevent exposure to flammable vapor or combustible dust clouds. Furnaces should
not be located in hazardous (classified) locations unless they are designed to
comply with the applicable requirements of NFPA 70 ANational Electric Code@
(see Appendix B).

3-1.7 Equipment shall be protected from corrosive external processes and environments,

including fumes or materials from adjacent processes or equipment that produces
corrosive conditions when introduced into the furnace environment.

3-1.8 The furnace is not intended for outdoor installation and must be sheltered from

weather. Unheated shelters may result in non-uniform temperatures or insufficient
heat to attain maximum operating temperature. Condensation may also occur
which would be detrimental to the steel structure and electrical components.

3-1.9 Suitable portable fire extinguishers should be available and operators trained in their

use. All such fire protection equipment should be inspected periodically in
accordance with appropriate standards. Reference NFPA 10 AStandard for
Portable Fire Extinguishers@ (see Appendix B).

3-2 BUILDING CONSIDERATIONS

3-2.1 When selecting the location for a furnace, consideration must be given to the

possibility of fire, building damage and personal injury. Hazards to be considered
include overheating of material in the furnace and escape of fuel gas or exhaust
into the work place.

3-2.2 Furnaces shall be located and erected so that the building structural members are

not affected adversely by the maximum anticipated temperature or by the additional
loading caused by the furnace and load.

3-2.3 Furnaces should be placed on noncombustible floors or on structures approved for

use over combustible floors such as concrete floor slabs or hollow tiles.

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3-2.4 Level the furnace using shims, if necessary. Where mounting holes are provided,

anchor the furnace securely. Shims should be permanently mounted to the furnace
after installation.

3-3 CLEARANCES

3-3.1 Furnaces shall be located with adequate space above and on all sides to allow for

inspection, maintenance and operator access. Provisions also shall be included for
unobstructed discharge of building sprinklers, the installation of automatic fire
protection system within the furnace, if necessary and the proper functioning of
explosion relief doors and panels.

3-3.2 Do not place the furnace up against a wall. A minimum air space of 12 inches must

be provided on all sides to allow for air circulation, with additional space being
provided for furnaces operating over 1400°F (760°C) to keep temperature at
adjacent structures and materials below 160°F (70°C). Local, city and state codes
may specify building requirements and special provisions for locating furnaces.

3-3.3 The furnace should be located so there is unrestricted air circulation around all

motors for proper cooling.

3-3.4 Do not store material on top of furnace. The furnace is not designed to support

external loads and material may get hot, ignite and cause a fire.

3-3.5 To prevent ignition of combustible material, combustible material shall be located at

a safe distance from furnace and furnace ductwork. The National Fire Protection
Association (NFPA) Standard 86 specifies a minimum distance of 2-1/2 feet;
Factory Mutual (FM) specifies at least 10 feet.

3-3.6 The furnace door travel must not be restricted and should face away from main

aisles, work areas and automatic sprinkler risers, feeds and cross mains.

3-4 VENTILATION

3-4.1 Where furnaces are located in basements or enclosed areas, sufficient room

ventilation shall be supplied to provide required combustion air for fuel fired
equipment and to prevent the hazardous accumulation of vapors from processing.

3-4.2 Furnaces designed for use with fuel gas or process gas having a specific gravity

greater than air (such as propane) shall be located at or above grade and shall be
located to prevent the escape of the fuel gas from accumulating in basements, pits,
or other areas below the furnace.

3-4.3 Fresh air inlets and exhaust outlets (if applicable) must never be restricted. If

filtered air is provided, there must be adequate filter capacity to prevent any
reduction in airflow even under adverse loading of the filter. The filters must be
periodically inspected and replaced as required.

3-4.4 A sufficient quantity of building make-up air should be admitted to furnace rooms

and buildings to provide the air volume required for furnace safety ventilation and
adequate combustion air for fuel fired equipment. Buildings should not operate
under a negative pressure.

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3-4.5 Some furnaces are equipped with an exhaust outlet. This outlet must be vented by

an exhaust flue to an exhaust stack for discharge to an outside location, in
accordance with local codes and requirements. Do not connect exhaust outlet
directly to exhaust stack. Exhaust gas temperature is the same as internal furnace
temperature. Reduce exhaust temperatures by diluting with room air before
ducting to the outside. Caution must be taken to protect combustible building
materials from coming in contact with the hot exhaust stack.

3-4.6 The minimum safe exhaust rate must be confirmed for furnaces equipped with a

powered forced exhauster to handle flammable solvent vapors or products of
combustion from fuel fired equipment. The exhaust rate has been set at the factory
and dampers cut off and screwed in place or in some other manner limited to
prevent exhaust rate from being reduced below safe minimum exhaust rate.

After installation, this exhaust rate must be confirmed. This must be done at the
outlet of the stack from the building. The exhaust rate must meet or exceed the
minimum rate indicated on the Safety Design Form located on the side of the
furnace. If it is necessary to open the exhaust damper to increase the exhaust rate,
it must be cutoff or locked in position to prevent accidental closing.

Exhaust rate must be checked again if any changes are made to ventilation
system, duct work or building ventilation. Adding additional equipment, which
requires ventilation, to the building will require additional make-up air to the building
to prevent the building from operating under negative pressure. Operating building
under negative pressure will reduce exhaust rate from furnace to below safe
minimum exhaust rate.

Fuel fired furnaces without powered forced exhauster must have unrestricted
negative pressure (room not under negative pressure) stack to remove products of
combustion from work area.

3-4.7 For additional ventilation information, refer to NFPA 31 AStandard for the

Installation of Oil-Burning Equipment@, NFPA 54 ANational Fuel Gas Code@ and
NFPA 91 AStandard for Exhaust systems for Air Conveying of Vapors, Gases,
Mists and Noncombustible Particulate Solids@ (see Appendix B).

3-5 EXHAUST DUCTWORK

3-5.1 Wherever furnace ducts or stacks pass through combustible walls, floors, or roof,

either non-combustible insulation or clearance, or both, shall be provided to prevent
combustible surface temperatures from exceeding 160°F (72EC).

3-5.2 Where ducts pass through non-combustible walls, floors or partitions, the space

around the duct shall be sealed with non-combustible material to maintain the fire
rating of the barrier. Ducts that pass through fire walls should be avoided. Local,
city and state codes may apply to duct installation.

3-5.3 Exhausts systems should be installed in accordance with Chapter 1, 2 and 3 of

NFPA 91 AStandard for Exhaust Systems for Air Conveying of Vapors, Gases,
Mists, and Noncombustible Particulate Solids@ (see Appendix B).

3-5.4 Ducts shall be constructed entirely of sheet steel or other non-combustible material

capable of meeting the intended installation and conditions of service. The
installation shall be of adequate strength and rigidity and shall be protected where
subject to physical damage.

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3-5.5 Ducts handling fumes that leave a combustible deposit shall be provided with

clean-out doors and such doors should be equipped with tight fitting doors or
covers. It is important that furnaces and ducts be kept clean if they are subjected
to a build-up of flammable deposits of condensed solvent, oil vapors, dust or other
combustible debris. The build-up of condensed vapors or combustible debris is a
major cause of fires. Frequency of cleaning should be based on never allowing
build-up to exceed 1/8" thickness in any location.

3-5.6 No portions of the building shall be used as an integral part of the duct.
3-5.7 All ducts shall be made tight throughout and shall have no openings other than

those required for the operation and maintenance of the system. All interior laps in
the duct joints should be made in the direction of the flow.

3-5.8 All ducts shall be thoroughly braced where required and substantially supported by

metal hangers or brackets.

3-5.9 Ducts handling flammable vapors shall be designed to minimize the condensation

of the vapors out of the exhaust stream onto the surface of the ducts. One method
is to insulate the ducts. If flammable condensation cannot be avoided, ducts
should be pitched to drain to suitable traps or other safe locations.

3-5.10 Ducts handling combustible solids shall be designed to minimize the accumulation

of solids within the ducts.

3-5.11 Exhaust ducts that will contain combustible deposits of any type require automatic

sprinklers in accordance with NFPA 13 AStandard for Installation of Sprinkler
Systems@ (see Appendix B).

3-5.12 Exhaust ducts shall not discharge near building openings or other air intakes that

allow re-entry of effluents into the building.

3-5.13 Clearance between metal ducts and stored combustible material should be at least

2-1/2 feet. Guards should be installed to assure this clearance.

3-5.14 Multiple exhaust fans manifolded together should have manifold designed so that

operation of one or more exhaust fan does not create a hazard such as back flow
to an idle furnace or reduced exhaust flow due to increased manifold pressure.

3-5.15 Duct work should not include dampers that could be closed and restrict flow within

the duct work.

3-6 FUEL GAS SUPPLY

3-6.1 Piping from the point of delivery to the equipment should comply with NFPA 54,

National Fuel Gas Code. Local, city and state codes should be followed. Gas
source pressure must be less than 60 psig.

3-6.2 A gas filter or strainer and sediment trap with vertical leg (drip leg) at least 3 pipe

diameters long (3" minimum) of same size as supply piping, shall be installed in the
fuel gas supply piping to protect the downstream safety shutoff valves and regulator
from materials that could interfere with their operation.

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3-6.3 All gas heated equipment shall be provided with an individual gas pressure

regulator properly sized to supply the pressure and volume required. The furnace
nameplate lists the gas pressure and the burner capacity. Gas pressure regulator
should have the following characteristics:
a. The regulator must be of the full lock-up type; gas pressure must be regulated

even under no flow condition.
b. Incoming pipe size should not exceed 2" diameter.
c. Self contained with no external static or control piping.
d. Single port with correctly sized orifice for the maximum gas pressure at the

regulator inlet.
e. Valve seat is of resilient material designed to withstand abrasion of gas,

impurity in gas, cutting by the valve and to resist permanent deformation by

the valve port.
f. Capable of regulating downstream pressure under no flow conditions to not more

than 150 percent of the discharge pressure under flow conditions.
If these criteria are not met, a pressure relieving or limiting device is required as
outlined in the NFPA 54 National Fuel Gas Code.

3-6.4 A remotely located emergency manual shutoff valve shall be provided to allow the

fuel to be turned off in an emergency and shall be located so that fire or explosion
at the furnace does not prevent access to this valve. Operators should be
instructed on the location of this valve and allowed access to shut off fuel flow in an
emergency. Valve shall have permanently affixed visual indication of position and
be operable without tools.

3-6.5 An equipment isolation shutoff valve must be provided at each piece of equipment.

Valve shall be quarter turn with stop, permanently affixed visual indication of
position, and operable without tools. Valve handle must remain affixed and be
parallel to pipe when open and perpendicular to pipe when closed.

3-6.6 Regulators and high or low gas pressure switch vent lines shall be piped to a safe

location outside the building according to local codes. Protect outlet from water
entry and provide bug screen.

3-6.7 Vent lines from regulator and switches of a single furnace may be manifolded

together in such a manner that diaphragm rupture of one regulator or switch does
not back load others. The cross section of the vent manifold should be not less
than the area of the largest vent line plus 50% of additional lines.

3-6.8 Vent lines from multiple furnaces shall not be manifolded together.
3-6.9 A normally open vent valve between safety valves shall not be combined with other

vents. Care must be taken to terminate a vent valve line in a safe approved
location.

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