USACE / NAVFAC / AFCESA / NASA UFGS-23 82 00.00 20 (November 2008)
-----------------------------------
Preparing Activity: NAVFAC Superseding
UFGS-23 82 00.00 20 (April 2006)
UNIFIED FACILITIES GUIDE SPECIFICATIONS
References are in agreement with UMRL dated January 2009
SECTION 23 82 00.00 20
TERMINAL HEATING AND COOLING UNITS
11/08
NOTE: This guide specification covers the requirements for unit heaters and
infrared heaters.
Edit this guide specification for project specific requirements by adding, deleting,
or revising text. For bracketed items, choose applicable items(s) or insert
appropriate information.
Remove information and requirements not required in respective project, whether
or not brackets are present.
Comments and suggestions on this guide specification are welcome and should
be directed to the technical proponent of the specification. A listing of technical
proponents, including their organization designation and telephone number, is
on the Internet.
Recommended changes to a UFGS should be submitted as a Criteria Change Request
(CCR).
PART 1 GENERAL
1.1 REFERENCES
NOTE: This paragraph is used to list the publications cited in the text of
the guide specification. The publications are referred to in the text by basic
designation only and listed in this paragraph by organization, designation,
date, and title.
Use the Reference Wizard's Check Reference feature when you add a RID outside
of the Section's Reference Article to automatically place the reference in the
Reference Article. Also use the Reference Wizard's Check Reference feature
to update the issue dates.
References not used in the text will automatically be deleted from this section
of the project specification when you choose to reconcile references in the
publish print process.
The publications listed below form a part of this specification to the extent referenced. The publications are
referred to within the text by the basic designation only.
[AMERICAN SOCIETY OF HEATING, REFRIGERATING AND AIR-CONDITIONING ENGINEERS (ASHRAE)
ASHRAE 33(2000) Method of Testing Forced Circulation
Air Cooling and Air Heating Coils
]
[ASTM INTERNATIONAL (ASTM)
ASTM A 1011/A 1011M(2008) Standard Specification for Steel, Sheet,
and Strip, Hot-Rolled, Carbon, Structural, High-Strength
Low-Alloy and High-Strength Low-Alloy with Improved
Formability
ASTM A 109/A 109M(2008) Standard Specification for Steel, Strip,
Carbon (0.25 Maximum Percent), Cold-Rolled
ASTM A 123/A 123M(2008) Standard Specification for Zinc (Hot-Dip
Galvanized) Coatings on Iron and Steel Products
ASTM A 167(1999; R 2004) Standard Specification for Stainless
and Heat-Resisting Chromium-Nickel Steel Plate,
Sheet, and Strip
ASTM A 463/A 463M(2006) Standard Specification for Steel Sheet,
Aluminum-Coated
ASTM A 653/A 653M(2008) Standard Specification for Steel Sheet,
Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated
(Galvannealed) by the Hot-Dip Process
ASTM B 117(2007a) Standing Practice for Operating Salt
Spray (Fog) Apparatus
ASTM B 209(2007) Standard Specification for Aluminum and
Aluminum-Alloy Sheet and Plate
ASTM B 209M(2007) Standard Specification for Aluminum and
Aluminum-Alloy Sheet and Plate (Metric)
ASTM D 1654(2008) Evaluation of Painted or Coated Specimens
Subjected to Corrosive Environments
]
[CANADIAN STANDARDS ASSOCIATION (CSA)
CSA 2.6(2006) Gas Unit Heater and Gas-Fired Duct Furnaces
]
[CSA AMERICA, INC. (CSA/AM)
CSA/AM Z83.19(2001; R 2005; Addenda 2007) Gas-Fired Infrared
Heaters
]
[NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA)
NEMA ICS 2(2000; Errata 2002; R 2005; Errata 2006) Standard
for Industrial Control and Systems: Controllers,
Contractors, and Overload Relays Rated Not More
than 2000 Volts AC or 750 Volts DC: Part 8 -
Disconnect Devices for Use in Industrial Control
Equipment
NEMA ICS 6(1993; R 2006) Standard for Industrial Controls
and Systems Enclosures
NEMA MG 1(2007; Errata 2008) Standard for Motors and
Generators
]
[NATIONAL FIRE PROTECTION ASSOCIATION (NFPA)
NFPA 211(2006) Chimneys, Fireplaces, Vents, and Solid
Fuel-Burning Appliances
NFPA 54(2008) National Fuel Gas Code
NFPA 70(2007; AMD 1 2008) National Electrical Code
- 2008 Edition
NFPA 90A(2008) Standard for the Installation of Air
Conditioning and Ventilating Systems
NFPA 90B(2008) Installation of Warm Air Heating and
Air Conditioning Systems
NFPA 91(2004) Exhaust Systems for Air Conveying of
Vapors, Gases, Mists and Noncombustible Particulate
Solids
]
[UNDERWRITERS LABORATORIES (UL)
UL 441(1996; Rev thru Aug 2006) Gas Vents
UL 731(1995; Rev thru Dec 2008) Oil-Fired Unit Heaters
]
1.2 RELATED REQUIREMENTS
Section 23 03 00.00 20 BASIC MECHANICAL MATERIALS AND METHODS, applies to this section with additions and modifications
specified herein.
1.3 SUBMITTALS
NOTE: Review submittal description (SD) definitions in Section 01 33 00 SUBMITTAL
PROCEDURES and edit the following list to reflect only the submittals required
for the project. Submittals should be kept to the minimum required for adequate
quality control.
A “G” following a submittal item indicates that the submittal requires Government
approval. Some submittals are already marked with a “G”. Only delete an existing
“G” if the submittal item is not complex and can be reviewed through the Contractor’s
Quality Control system. Only add a “G” if the submittal is sufficiently important
or complex in context of the project.
For submittals requiring Government approval on Army projects, a code of up
to three characters within the submittal tags may be used following the "G"
designation to indicate the approving authority. Codes for Army projects using
the Resident Management System (RMS) are: "AE" for Architect-Engineer; "DO"
for District Office (Engineering Division or other organization in the District
Office); "AO" for Area Office; "RO" for Resident Office; and "PO" for Project
Office. Codes following the "G" typically are not used for Navy, Air Force,
and NASA projects.
Choose the first bracketed item for Navy, Air Force and NASA projects, or choose
the second bracketed item for Army projects.
Government approval is required for submittals with a "G" designation; submittals not having a "G" designation
are [for Contractor Quality Control approval.][for information only. When used, a designation following the
"G" designation identifies the office that will review the submittal for the Government.] The following shall
be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:
SD-03 Product Data
Unit heaters
Infrared heaters
SD-10 Operation and Maintenance Data
Unit heaters, Data Package 2
Infrared heaters, Data Package 2
Submit in accordance with Section 01 78 23 OPERATION AND MAINTENANCE DATA.
PART 2 PRODUCTS
2.1 UNIT HEATERS
Self-contained and factory assembled, [propeller] [or] [centrifugal] fan with capacities expressed as Btu per
hour output and cubic foot-per-minute air delivery, operating conditions, and mounting arrangements as indicated.
Average fan bearing life shall be minimum 200,000 hours at operating conditions. Provide fan motor with [direct]
[or] [belt] drive. Construct fan-guard motor mount of steel wire. Equip each heater with individually adjustable
package discharge louver. Louvers may be substituted by discharge cones or diffusers. Provide thermostats [as
indicated]. Furnish circuit breaker disconnect switch.
2.1.1 Gas-Fired Unit Heater
CSA 2.6 and AGA label.
2.1.1.1 Casing
Minimum [22] [_____] gage [steel] [or] [aluminum]. Provide removable access panels.
2.1.1.2 Heat Exchanger
Minimum [20] [_____] gage all-welded steel construction with corrosion-resistant aluminum finish.
2.1.1.3 Burners
Die-formed, slot ports, and steel construction with aluminum paint.
2.1.1.4 Draft Diverter
All-welded steel construction and an integral part of each heat exchanger section. Allows backdrafts to bypass
burner assembly without affecting normal operation.
2.1.1.5 Controls
Consisting of a combination pressure regulator, [two-stage gas valve in 100 percent and [55] [_____] percent
of full rating,] main shutoff valve, pilot cock, pilot safety switch for 100 percent shutoff, high temperature
limit switch, and time-delay fan switch. Include power and control connections in an integral junction box.
2.1.1.6 Efficiency
Minimum steady state efficiencies shall be 78 percent at maximum rated capacity and 75 percent at minimum rated
capacity that is provided and allowed by the controls.
[2.1.1.7 Accessories
NOTE: Do not acquire propane-gas conversion kit for project locations where
it is not cost effective to use propane gas as fuel. Delete this paragraph
if not required.
Provide [propane-gas conversion kit] [automatic electric pilot recognition kit].
]2.1.2 Oil-Fired Unit Heater
UL 731 and UL labeled.
2.1.2.1 Casing
Minimum [22] [_____] gage [aluminum] [or] [[enamel] [or] [vinyl] coated steel]. Provide removable access door.
2.1.2.2 Heat Exchanger
Minimum 16 gage primary combustion chamber constructed of [perlite-clad steel] [, aluminum-clad steel] [, or]
[400 series stainless steel]; minimum 14 gage secondary heating section composed of aluminized, mild, or hot-rolled
steel. Provide a flame observation port on the burner side of the heater.
2.1.2.3 Burner
Provide pressure oil-atomizing burner with mechanically forced draft, suitable for fuel oil No. 2. Provide two-stage
oil pump. Equip burner motor with a combustion air damper.
2.1.2.4 Controls
Include fan and limit switch, low voltage (24-volt) transformer, electronic flame safeguard with flame safety
relay, and electric spark ignition.
2.1.2.5 Accessories
Provide [power exhauster,] oil filter, oil pressure regulator, and barometric damper.
2.1.2.6 Efficiency
Minimum steady state efficiencies shall be 81 percent at maximum rated capacity and 78 percent at minimum rated
capacity that is provided and allowed by the controls.
2.1.3 [Steam] [or] [Hot-Water] Unit Heater
ASHRAE 33 tested for heating coils; UL listed for motor and controls.
2.1.3.1 Casing
Minimum [20] [_____] gage [steel] [or] [aluminum] with removable access panels or means to remove, service, and
maintain major components.
2.1.3.2 Coil
NOTE: Use copper for maximum 517 kPa (gage) 75 psig steam or maximum 163 degrees
C 325 degrees F hot water at 1379 kPa (gage) 200 psig, red brass for maximum
1379 kPa (gage) 200 psig steam or 218 degrees C 425 degrees F hot water at
2068 kPa (gage) 300 psig, copper nickel for maximum 2758 kPa (gage) 400 psig
steam or maximum 232 degrees C 450 degrees F at 4136 kPa (gage) 600 psig, and
steel for maximum 232 degrees C 450 degrees F hot water at 4136 kPa (gage) 600
psig.
Fin-and-tube coil constructed of [copper,] [red brass,] [90-10 copper nickel,] [or ] [steel] tubes and [copper]
[or] [aluminum] fins. Use maximum design pressure of [steam at [_____] kilopascal (kpa (gage)) pounds per square
inch gage (psig)] [and] [hot water at [_____] kpa (gage) psig and [_____] degrees C F].
2.1.3.3 Controls
[Automatic controls of [modulating] [on-off-auto] [or] [combination of modulating and on-off-auto] system] [As
indicated]. [Provide a three-position selector switch.]
2.1.4 Electric Unit Heater
NOTE: Check if Section 15768, "Electric Space Heating Equipment," covers electric
unit heater. Recommend to cover unit heaters exclusively in this section. Avoid
redundant statement.
UL listed; wattage, voltage, phase, and number of steps as indicated. Provide control-circuit terminals and single
source of power supply. Heater 5 Kw and larger shall be three-phase, with load balanced on each of the three
phases. Limit leaving air temperature below 60 degrees C at 15.5 degrees C 140 degrees F at 60 degrees F entering
air.
2.1.4.1 Casing
Minimum [21] [_____] gage steel.
2.1.4.2 Heating Element
Nickel-chromium heating wire element, free from expansion noise and 60 Hz hum. Embed element in magnesium-oxide
insulating refractory. Seal element in high-mass steel or corrosion-resisting metallic sheath with fins. Enclose
element ends in terminal box. Space fins at maximum six fins per inch. Limit fin surface temperature 288 degrees
C 550 degrees Fat any point during normal operation.
2.1.4.3 Controls
Include limit controls for thermal overheat protection of heaters. For remote thermostatic operation, provide
contactor rated for 100,000 duty cycles. [Provide a control transformer to supply 120-volt thermostat control
circuit for each heater.] Provide room thermostat for pilot duty.
2.1.4.4 Wiring
Completely factory-prewired to terminal strips, ready to receive branch circuit and control connections for 60
degrees C 140 degrees F[copper] [or] [aluminum] wiring.
[2.1.4.5 Accessories
NOTE: These accessories are not integral components of electric unit heater.
Delete this paragraph if not required.
Provide fan switching devices to independently operate fan motor for summer ventilation and winter heat recovery.
]2.2 INFRARED HEATERS
NOTE: Check if Section 15768, "Electric Space Heating Equipment," covers electric
unit heater. Recommend to cover unit heaters exclusively in this section. Avoid
redundant statement.
[Reflector-beam spread] [and] operating conditions as indicated. Provide pre-wired control boxes, thermostats,
and reflector [and duct] hangers.
2.2.1 Sheet Metal
[a. Aluminum-Clad Steel: ASTM A 463/A 463M, nominal thickness of minimum 16 gage for radiant
tubing between burners and vacuum pump or vent.]
[b. Aluminum: ASTM B 209M ASTM B 209, manufacturer's standard thickness.]
[c. Stainless Steel: ASTM A 167, nominal thickness of not less than 20 gage.]
[d. [Ceramic-Coated] [Enamel-Coated] Steel: ASTM A 1011/A 1011M hot rolled orASTM A 109/A 109M
cold rolled, low-carbon steel. Provide coating able to withstand infrared heater operating
temperatures.]
2.2.2 Unvented Gas Infrared Heater
NOTE: Use only if adequate ventilation ensured for the project location.
CSA/AM Z83.19 and AGA approved.
2.2.2.1 Heating Element
Perforated ceramic capable of withstanding thermal shock in [3] [_____] minutes from 1093 to 0 degrees C 2000
to 32 degrees F without fatigue and of minimum 871 degrees C 1600 degrees F operating temperature. When re-radiating
screens are used to obtain operating temperature, provide [stainless-steel] [or] [chromized-steel] matching screen.
2.2.2.2 Reflector
[Polished [aluminum] [stainless steel]] [or] [approved high infrared reflector materials]. Provide reflector
supports of manufacturer's standard.
2.2.2.3 Controls
Provide either an intermittent pilot ignition system or a solid-state direct ignition system. Provide automatic
gas safety valve capable of withstanding a 10 percent voltage fluctuation.
2.2.2.4 Ventilation
Section 23 00 00 AIR SUPPLY, DISTRIBUTION, VENTILATION, AND EXHAUST SYSTEMS.
2.2.3 Vented Gas Infrared Heater
NOTE: For spot heating, use single-burner power vented heater; for small area
heating, uses single-burner vacuum vented heater; and for large area or entire
building heating, use multiple-burner vacuum vented heater. Do not use vented
gas infrared heaters in projects in the SOUTHNAVFACENGCOM area.
CSA/AM Z83.19 with AGA label, [single-burner power vented] [single-burner vacuum vented] [or] [multiple-burner
vacuum vented].
2.2.3.1 Vent
NFPA 54 and NFPA 211, [Type 316 stainless steel] [or] [high-temperature corrosion-resistant plastic rated for
minimum 204 degrees C 400 degrees F]. Vent flue gas to outdoors by induced draft.
2.2.3.2 Reflector
[Polished [aluminum] [stainless steel]] [or] [approved high infrared reflector materials]. Provide manufacturer's
standard reflector supports.
2.2.3.3 Heat Exchanger and Combustion Chamber
Construct heat exchanger and combustion chamber of [aluminum-clad steel] [ceramic-coated steel] [or] stainless
steel.
2.2.3.4 Controls
Incorporate either an intermittent pilot ignition system or a solid-state direct ignition system. Provide safety
air-flow switch for each burner.
2.2.3.5 Fan or Vacuum Pump
Heater manufacturer's standard.
2.2.3.6 Performance
NOTE: Performance Criteria are:
Minimum Steady Maximum Heat
State Thermal Release (kJ
Efficiency Per Square Meter
(Percent) of Heating
Surface
Single-Burner 80 31,350
Power Vented
Heater
Single-Burner 80 33,060
Vacuum Vented
Heater
Multiple-Burner 85 23,940
Vacuum Vented
Heater
Minimum Steady Maximum Heat
State Thermal Release (BTU
Efficiency Per Square Foot
(Percent) of Heating
Surface
Single-Burner 80 2,750
Power Vented
Heater
Single-Burner 80 2,900
Vacuum Vented
Heater
Multiple-Burner 85 2,100
Vacuum Vented
Heater
Provide sufficient radiant heating surface to attain a minimum steady-state thermal efficiency of [80] [85] percent
and a maximum heat release of [31,350] [33,060] [23.940] kJ per square meter [2,750] [2,900] [2,100] Btu per
square foot.
2.2.4 Electric Infrared Heater
NOTE: Check if Section 15768, "Electric Space Heating Equipment," covers electric
unit heater. Recommend to cover unit heaters exclusively in this section. Avoid
redundant statement.
Self-contained, factory assembled, and UL listed and including the heating element, reflector, heater housing,
mounting brackets, element holders, wire guards, and high-temperature internal wiring.
2.2.4.1 Heating Element
Minimum 9 1/2 mm 3/8 inch diameter quartz tube or metal sheath with coiled resistor wire. Element operating
temperature range shall be 649 to 982 degrees C 1200 to 1800 degrees F.
2.2.4.2 Heater Housing
[Weatherproof] [aluminum-clad steel] [stainless-steel] [aluminum] [or] [low-carbon steel] construction. Provide
a baked enamel finish over a corrosion-resistant primer. Provide a chrome-plated or stainless-steel wire guard
to prevent heating elements from accidental damage. Furnish swivel brackets to position heater in any horizontal
angle.
2.2.4.3 Reflector
Polished [aluminum] [or] [stainless steel].
2.2.4.4 Wiring
Fully enclosed internal wiring. Provide minimum 152 mm 6 inchslack fixture (heater) wire for connection to branch
circuit wiring.
[2.2.4.5 Accessories
NOTE: Electric-clock controller is an input controller provided separately
as an optional addition to unit heaters. Delete this paragraph if not required.
Provide electric-clock controller with self-starting synchronous motors and snap acting switch, rated for 125
percent of the load which it controls. Provide a 30-second time cycle with an infinitely adjustable "on-off"
period each cycle. Equip controller with external indicating knob for manual adjustment from zero to 100 percent.
If surface mounted, furnish steel enclosure with a baked enamel finish over a corrosion-resistant primer. If
flush mounted, furnish galvanized steel enclosure with knockouts for conduit in bottom and sides. Provide a
connection wiring diagram on the inside cover of the enclosure. Where loads exceed the maximum available rating
of controller, provide high duty-cycle contactors serving as pilot devices.
]2.3 FAN
Provide [steel] [or] [aluminum] fans with ball or roller bearings for motors over 0.09 kW 1/8 horsepower (hp)
and sleeve bearings for motors 0.09 kW 1/8 hp and under. Provide sleeve bearings with oil reservoir, if not
permanently lubricated.
2.4 MOTOR AND STARTER
NOTE: The motor control requirements should be coordinated with the electrical
section and will depend on field conditions. The following types of motor starters
should be used as a guide only. When electrical power circuits to which equipment
are connected are heavily loaded, the full voltage-across line starting may
result in excessive voltage drop on the circuit.
Motor kW Voltage Type Starter
Up to 5 1/2 208-230 Across line magnetic
5 1/2 to 11 208-230 Across line magnetic,
part wind or wye delta
11 to 22 3/8 460 Across line magnetic part
wind or wye delta
Above 11 208-230 Part wind or wye delta
Above 22 3/8 460 Part wind or wye delta
Motor hp Voltage Type Starter
Up to 7-1/2 208-230 Across line magnetic
7-1/2 to 15 208-230 Across line magnetic,
part wind or wye delta
15 to 30 460 Across line magnetic part
wind or wye delta
Above 15 208-230 Part wind or wye delta
Above 30 460 Part wind or wye delta
NEMA MG 1, and NEMA ICS 2, and NEMA ICS 6, respectively. [Provide explosion-proof motors and motor starters
where indicated.] Provide continuous-duty motor with built-in automatic reset thermal overload protection. For
motor 0.37 kW 1/2 hp and larger, use three-phase. Provide single-phase motor of permanent split capacitor or
capacitor start. Limit motor speed at 1800 rpm r/min. Wire motor to heater power supply source.
2.5 [NOISE, VIBRATION AND SEISMIC CONTROLS
NOTE: Depending upon various heaters, delete any irrelevant paragraph for piping
systems.
Section 22 05 48.00 20 MECHANICAL SOUND VIBRATION AND SEISMIC CONTROL.]
[2.6 GAS PIPING SYSTEM AND FLUE VENT
Comply with Section 23 11 25 FACILITY GAS PIPING, Section 33 51 15 NATURAL-GAS / LIQUID PETROLEUM DISTRIBUTION,
for gas valves and piping. Use UL 441 flue vents [and] [gas-vent roof jacks], of [galvanized steel] [aluminum]
[or] [stainless steel].
][2.7 FUEL OIL [TANK] AND PIPING SYSTEM
Section 33 52 10 SERVICE PIPING, FUEL SYSTEMS.
][2.8 HOT WATER PIPING SYSTEM
Section 23 21 13.00 20 LOW TEMPERATURE WATER [LTW] HEATING SYSTEMS.
][2.9 STEAM AND CONDENSATE PIPING SYSTEM
Section 23 22 26.00 20 STEAM SYSTEM AND TERMINAL UNITS.
]2.10 SOURCE QUALITY CONTROL
Special protection is not required for equipment that has a zinc coating conforming to \&[ASTM A 123/A 123M
] [ASTM A 653/A 653M]&\. Otherwise, protect affected equipment items by manufacturers' corrosion-inhibiting
coating or paint system that has proved capable of withstanding salt-spray test in accordance with ASTM B 117
. Test indoor and outdoor equipment for 125 hours; test outdoor equipment used in a marine atmosphere for 500
hours. For each specimen, perform a scratch test as defined in ASTM D 1654.
PART 3 EXECUTION
3.1 INSTALLATION
Install equipment where indicated and as recommended by manufacturer's recommendations, NFPA 54, NFPA 90A, NFPA 90B
, NFPA 91 and NFPA 211.
3.1.1 Suspensions of Equipment
Provide equipment supports including beam clamps, turnbuckles and twist links or weld-wire chains, wire ropes
with rope clips and rope thimbles, threaded-eye rod hangers with lock nuts and heat-duct hangers, threaded-eye
bolts with expansion screws, brackets, platform and mounting frame, and vibration isolators. Locate equipment
in such a manner that working space is available for servicing, such as vacuum pump and burner removal, access
to automatic controls, and lubrication. Provide electrical isolation of dissimilar metals. Clean interior of
casings or cabinets before and after completion of installation.
3.1.2 Vents
NFPA 54 and NFPA 211. Provide vents with weatherproofing flashings in accordance with Section 07 57 13 FLASHING
AND SHEET METAL.
3.1.3 Electrical Work
NFPA 70 and Division 16, "Electrical Work." When replacing original control wires, provide No. 16 AWG with
minimum 105 degrees C insulation.
3.2 FIELD QUALITY CONTROL
Administer, schedule, and conduct specified tests. Furnish personnel, instruments and equipment for such tests.
Correct defects and repeat the respective inspections and tests. Conduct inspections and testing in the presence
of the Contracting Officer.
3.2.1 Test Instruments and Apparatus
Provide instruments and apparatus currently certified as being accurate to within one percent of their full scale.
Use gages with a maximum scale between 1 1/2 and 2 times test pressure.
3.2.2 Field Inspection
Prior to initial operation, inspect equipment installation to ensure that indicated and specified requirements
have been met.
3.2.3 Field Tests
3.2.3.1 Fuel Piping Pressure Tests
[Pneumatically test gas piping at 1 1/2 times operating pressure and check for leakage with soap solution.]
[Hydrostatically test fuel oil piping at 1 1/2 times maximum working pressure.]
3.2.3.2 Fire Tests for Nonelectrical Heating Equipment
Test combustion controls and equipment with specified fuel at 100 percent full rated load. During tests, verify
proper operation of controls. Adjust burners for maximum efficiency using Orsat or similar apparatus. Maintain
firing for at least four hours [, and where high-low-off combustion controls are provided, operate the heating
equipment for one hour at low fire and 3 hours at high fire]. For acceptable combustion efficiency, allow maximum
4.5 percent carbon dioxide in flue gases.
3.2.3.3 Insulation-Resistance Tests for Electrical Equipment
At the completion of wiring, test 600 volt wiring to verify that no short circuits exist before or after the
attachment of electrical heating equipment to the power source. Make tests with an instrument which applies
a voltage of approximately 500 volts for a direct reading of insulation resistance.
3.2.3.4 Operational Tests
After completing fire tests and insulation-resistance tests, operate equipment continuously under varying load
conditions to verify functioning of combustion controls, electrical controls, flame safeguard controls, safety
interlocks, and specified operating sequence. Run each test for a minimum period of one hour.
3.3 SCHEDULE
Some metric measurements in this section are based on mathematical conversion of inch-pound measurements, and
not on metric measurements commonly agreed on by the manufacturers or other parties. The inch-pound and metric
measurements shown are as follows:
Products Inch-Pound Metric
a. Motor
Capacity = 7 1/2 hp = 5 1/2 kW
= 15 hp = 11 kW
= 30 hp = 22 3/8 kW