Copyright 2015 AIA
MasterSpec Premium
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PRODUCT MASTERSPEC LICENSED BY ARCOM TO LAARS HEATING SYSTEMS.
This Product MasterSpec Section is licensed by ARCOM to Laars Heating Systems ("Licensee").
This Product MasterSpec Section modifies the original MasterSpec text.
Revisions made to the original MasterSpec text are made solely by the Licensee and are not endorsed by,
or representative of the opinions of, ARCOM or The American Institute of Architects (AIA). Neither
AIA nor ARCOM are liable in any way for such revisions or for the use of this Product MasterSpec
Section by any end user. A qualified design professional should review and edit the document to suit
project requirements.
For more information, contact Laars Heating Systems, 20 Industrial Way, Rochester, NH 03867; Phone:
(603) 335-6300; Fax: (603) 335-3355; Website: www.laars.com; Email: [email protected].
For information about MasterSpec contact ARCOM at (800) 424-5080 or visit www.MasterSpec.com.
SECTION 235233 - WATER-TUBE BOILERS
TIPS:
To view non-printing Editor's Notes that provide guidance for editing, click on Masterworks/Single-File
Formatting/Toggle/Editor's Notes.
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click on Masterworks/Supporting Information.
PART 1 - GENERAL
1.1
RELATED DOCUMENTS
A.
1.2
Drawings and general provisions of the Contract, including General and Supplementary
Conditions and Division 01 Specification Sections, apply to this Section.
SUMMARY
A.
Section includes packaged, factory-fabricated and -assembled, gas-fired, finned water-tube
boilers for generating hot water.
B.
Section includes packaged, [factory-] [or] [field-] assembled, water-tube boilers for generating
[hot water] [steam].
1.3
ACTION SUBMITTALS
A.
Product Data: For each type of product, include the following:
1.
Construction details, material descriptions, dimensions, and weights of individual
components, profiles, and finishes for boilers.
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2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
B.
Sustainable Design Submittals:
1.
C.
Rated capacities, operating characteristics, and furnished specialties and accessories.
Predicted boiler efficiency while operating at design capacity and at varying part loads
with basis indicated.
Predicted emissions levels while operating at design capacity and at varying part loads
with basis indicated. Indicate operation that produces worst-case emissions.
Technical data for refractory and insulation, including temperature rating, thermal
performance, attachment, and arrangement.
Calculations showing predicted surface temperature of boiler jacket with basis indicated.
Force and moment capacity of each piping and flue connection.
Dimensioned location of low, high, and normal water level, showing operating set point
and each alarm set point.
Temperature and pressure rating, size, and materials of construction for boiler trim
components, including piping, fittings, flanges, unions, and valves. Provide valve
manufacturer's product data for each valve furnished. For safety valves, include trip and
reset settings and flow capacity.
Manufacturer's product data showing size, scale range, and accuracy of thermometers and
pressure gages.
Pressure rating, size, and materials of construction for boiler fuel train components,
including piping, fittings, flanges, unions, switches, and valves. Provide manufacturer's
product data for each valve and switch furnished.
Detailed information of controls, including product data with technical performance,
operating characteristics, and sequence of operation.
Product data for each motor, including performance, operating characteristics, and
materials of construction.
Product Data: For energy performance.
Shop Drawings: For boilers, boiler trim, and accessories.
1.
2.
3.
Include plans, elevations, sections, and [mounting] [attachment] details.
Include details of equipment assemblies. Indicate dimensions, weights, loads, required
clearances, method of field assembly, components, and location and size of each field
connection.
Design calculations and base details, signed and sealed by a qualified professional
engineer.
a.
b.
4.
5.
Design Calculations: Calculate requirements for selecting [vibration isolators
and] seismic restraints and for designing bases.
Base Details: Detail fabrication, including anchorages and attachments to structure
and to supported equipment. Include adjustable motor bases, rails, and frames for
equipment mounting.
Include diagrams for power, signal, and control wiring. Differentiate between factory and
field installation.
Include piping diagrams of factory-furnished piping that indicate size and each piping
component.
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1.4
INFORMATIONAL SUBMITTALS
A.
Coordination Drawings: Plan and elevation views, drawn to <Insert scale> scale, indicating
equipment manufacturers' service clearances, structure and base attachment, piping, power,
controls, and flues. Each view shows a screened background with the following:
1.
2.
3.
B.
Column grids, beams, columns, and concrete housekeeping pads.
Room layout with walls, floors, and roofs, including each room name and number.
Equipment and products of other trades that are located in vicinity of boilers and are part
of final installation, such as lighting, fire-suppression systems, and plumbing systems.
Seismic Qualification Certificates: For boilers, accessories, and components, from
manufacturer.
1.
2.
3.
Basis for Certification: Indicate whether withstand certification is based on actual test of
assembled components or on calculation.
Dimensioned Outline Drawings of Equipment Unit: Identify center of gravity and locate
and describe mounting and anchorage provisions.
Detailed description of equipment anchorage devices on which the certification is based
and their installation requirements.
C.
Installation instructions.
D.
Source quality-control reports.
E.
Field quality-control reports.
F.
Sample Warranty: For special warranty.
G.
Other Informational Submittals:
1.
2.
1.5
ASME "A" Stamp Certification and Report: Submit "A" stamp certificate of
authorization as required by authorities having jurisdiction, and document hydrostatic
testing of piping external to boiler.
Startup service reports.
CLOSEOUT SUBMITTALS
A.
Operation and Maintenance Data: For boilers, components, and accessories to include in
emergency, operation, and maintenance manuals.
B.
Spare Parts List: Recommended spare parts list with quantity for each.
C.
Touch-up Paint Description: Detailed description of paint used in application of finish coat to
allow for procurement of a matching paint.
D.
Instructional Videos: Including those that are prerecorded and those that are recorded during
training.
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1.6
MAINTENANCE MATERIAL SUBMITTALS
A.
Tool kit to include the following:
1.
2.
3.
4.
B.
1.7
A tool kit specially designed by boiler manufacturer for use in servicing boiler(s)
furnished.
Special tools required to service boiler components not readily available to Owner service
personnel in performing routine maintenance.
Lockable case with hinged cover, marked with large and permanent text to indicate the
special purpose of tool kit, such as "Boiler Tool Kit." Text size shall be at least 1 inch (25
mm) high.
A list of each tool furnished. Permanently attach the list to underside of case cover. Text
size shall be at least 0.5 in. (13 mm) high.
Touch-up Paint: [32-oz. (1-L)] <Insert volume> container of paint used for finish coat. Label
on outside of container shall have a detailed description of paint to allow for procurement of a
matching paint in the future.
WARRANTY
A.
Special Warranty: Manufacturer agrees to repair or replace heat exchangers damaged by
thermal that fail in materials or workmanship within specified warranty period.
1.
B.
Special Warranty: Manufacturer agrees to repair or replace heat exchangers/pressure vessels of
boilers that fail in materials or workmanship within specified warranty period.
1.
C.
Warranty Period for Heat Exchangers: [25] <Insert number> years from date of
Substantial Completion or six months after date of manufacture.
Warranty Period for Heat Exchanger/Pressure Vessel: [10] <Insert number> years from
date of Substantial Completion or six months after date of manufacture, with years 6 – 10
prorated.
Special Warranty: Manufacturer agrees to repair or replace parts of boilers that fail in materials
or workmanship within specified warranty period.
1.
Warranty Period for Parts: [1] year from date of Substantial Completion or six months
after date of manufacture.
PART 2 - PRODUCTS
2.1
PERFORMANCE REQUIREMENTS
A.
Multiple Boiler Operation: Provide multiple boiler operation for optimum system performance,
energy efficiency, and the following:
1.
Equalize runtime of boilers in service.
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2.
3.
4.
B.
Operate multiple boilers hot to minimize disruption of service in the event of single boiler
failure.
Configure controls so any boiler can be taken out of service with power disconnected and
not impact multiple boiler operation.
<Insert requirement>.
Seismic Performance: Boiler shall withstand the effects of earthquake motions determined
according to [ASCE/SEI 7] <Insert requirement>.
1.
2.
3.
The term "withstand" means "the boiler will remain in place without separation of any
parts when subjected to the seismic forces specified[ and the boiler will be fully
operational after the seismic event]."
Component Importance Factor: [1.5] [1.0].
<Insert requirements for Component Amplification Factor and Component
Response Modification Factor>.
C.
Sound: Boiler sound level, measured according to parameters defined in ABMA publication
"Boiler 304 Measurement of Sound from Steam Generators" shall not exceed 70 <Insert
number> dBA.
D.
Operation Following Loss of Normal Power:
1.
2.
3.
E.
Equipment, associated factory- and field-installed controls, and associated electrical
equipment and power supply connected to back-up power system shall automatically
return equipment and associated controls to the operating state occurring immediately
before loss of normal power without need for manual intervention by an operator when
power is restored either through a back-up power source or through normal power if
restored before back-up power is brought online, unless prohibited by local jurisdiction.
Refer to Drawings for equipment served by back-up power systems.
Provide means and methods required to satisfy requirement even if not explicitly
indicated.
Outdoor Installations:
1.
Boiler shall be CSA certified for outdoor installation..
F.
Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, by
a qualified testing agency, and marked for intended location and application.
G.
ASME Compliance: Fabricate and label boilers to comply with the latest edition of the ASME
Boiler and Pressure Vessel Code.
H.
ASHRAE/IES 90.1 Compliance: Boilers shall have minimum efficiency according to "Gas and
Oil Fired Boilers - Minimum Efficiency Requirements."
I.
DOE Compliance:
1.
2.
3.
4.
Minimum efficiency shall comply with 10 CFR 431. Subpart E, Appendix N.
Boiler thermal and combustion efficiencies shall be certified and listed by AHRI.
Minimum efficiency shall comply with 10 CFR 430, Subpart B.
Boiler AFUE shall be certified and listed by AHRI.
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FINNED WATER-TUBE BOILERS (200 – 400 MBH)
2.2
A.
Basis-of-Design Product: Subject to compliance with requirements, provide Laars Heating
Systems Company: Mighty Therm2 or comparable product by one of the following:
1.
2.
3.
4.
Raypak, Inc.
RBI; A Division of Mestek, Inc.
Thermal Solutions LLC.
<Insert manufacturer's name>.
B.
Description: Factory-fabricated, -assembled, and -tested boiler, with tubes sealed into headers
pressure tight, and set on a steel base; including jacket, flue-gas vent connections, combustionair-intake connections, water supply and return connections, and controls.
C.
Heat Exchanger:
1.
2.
3.
4.
Finned copper tubing with stainless-steel baffles.
Cast-iron headers, glass-lined.
Two-pass, horizontal configuration.
Tubes shall be sealed in header by mechanically rolling tubes in header.
D.
Combustion Chamber Internal Insulation: Interlocking panels of refractory insulation, hightemperature cements, mineral fiber, and ceramic refractory tile for service temperatures of up to
2,000 deg F (1100 deg C).
E.
Casing:
1.
2.
3.
4.
5.
6.
F.
Jacket: Sheet metal, with snap-in, mechanically fastened, and/or interlocking closures.
Control Compartment Enclosure: Integral to boiler jacket.
Finish: Thermal set powder coat paint with textured finish.
Insulation: Minimum 1-inch- (25-mm-) thick, mineral-fiber insulation surrounding the
heat exchanger.
Combustion-Air Connection: Inlet air duct collar.
Mounting base to secure boiler.
Burner:
1.
Burner Tubes: Stainless steel, for [natural] [propane] gas.
a.
b.
c.
2.
3.
4.
Direct Vent: Factory-mounted centrifugal fan to draw flue gas out of boiler and
discharge into boiler vent.
Burner shall have a viewing port for observation of burner operation.
Boiler control will prepurge and postpurge the combustion chamber before firing.
Gas Train: Control devices and on/off control sequence shall comply with CSA
requirements. In addition to these requirements, include shutoff cock, pressure regulator,
and control valve.
Gas Train: Combination gas valve with manual shutoff.
Ignition: Proven hot surface ignition.
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G.
Hot-Water Boiler Trim:
1.
2.
3.
4.
5.
Hot-Water Temperature Controllers: Operating[, firing rate,] and high limit.
Safety Relief Valve: ASME rated.
Pressure and Temperature Gage: Minimum 3-1/2-inch- (89-mm-) diameter, combination
water-pressure and -temperature gage in compliance with ASME pressure vessel code.
Drain Valve: Minimum NPS 3/4 (DN 20) hose-end valve.
Options:
a.
b.
c.
d.
e.
f.
g.
H.
Controls:
1.
Boiler operating controls shall include the following devices and features:
a.
b.
c.
2.
Control transformer.
Set-Point Adjust: Set points shall be adjustable.
Sequence of Operation: Call for heat, prepurge, ignitor warmup, ignitor prove,
main gas ignition, main gas proof, end of call for heat, and post purge.
Burner Operating Controls: To maintain safe operating conditions, burner safety controls
limit burner operation.
a.
b.
c.
d.
I.
Two stage firing.
Cupronickel heat exchanger tubes.
Bronze trim.
200 deg F (93 deg C) high limit.
Boiler pump.
Low water cutoff with manual reset and test button.
Reversed water connections.
High Cutoff: Manual reset stops burner if operating conditions rise above
maximum boiler design temperature.
Water Flow Switch: Automatic-reset paddle-switch shall prevent burner operation
on low water flow.
Blocked Vent Safety Switch: Manual-reset switch factory mounted on draft
diverter.
Rollout Safety Switch: Factory mounted on boiler combustion chamber.
Capacities and Characteristics:
1.
2.
3.
4.
5.
6.
7.
8.
9.
Heating Medium: Hot water.
Design Pressure and Temperature Rating: [160 psig (1100 kPa), 250 deg F (120 deg C)]
<Insert values>.
Safety Relief Valve Setting: 75 psig (517 kPa) <Insert psig (kPa)>.
Entering-Water Temperature: Minimum 120 deg F (49 deg C) <Insert deg F (deg C)>.
Leaving-Water Temperature: Maximum 240 deg F (116 deg C) <Insert deg F (deg C)>.
Design Water-Flow Rate: [14 gpm (0.88 L/s)] [20 gpm (1.26 L/s)] [27 gpm (1.7 L/s)]
<Insert gpm (L/s)>.
Design Pressure Drop: [1.0 feet (2.96 kPa)] [2.3 feet (6.9 kPa)] [4.0 feet (11.9 kPa)]
<Insert feet (kPa)>.
AHRI Certified AFUE: 85.1 percent.
AHRI Certified Thermal Efficiency: 85.3 percent.
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10.
11.
12.
13.
14.
15.
AHRI Certified Combustion Efficiency: 83.4 percent.
NOx Emissions: Less than 10 ppm, adjusted to 3 percent O2.
Number of Passes: Two.
Gas Input: [200 Mbh (58.6 kW)] [299 Mbh (87.6 kW)] [399 Mbh (116.9 kW)] <Insert
Mbh (kW)>.
Gas Pressure: 4- to 13-in. wg (995 to 3235 Pa).
Electrical Characteristics:
a.
b.
c.
d.
Volts: 115-V ac.
Phase: Single.
Hertz: 60 hz.
Minimum Circuit Ampacity: 15-A.
FINNED WATER-TUBE BOILERS (500 – 2,000 MBH)
2.3
A.
Basis-of-Design Product: Subject to compliance with requirements, provide Laars Heating
Systems Company; Mighty Therm2 or comparable product by one of the following:
1.
2.
3.
4.
Raypak, Inc.
RBI; A Division of Mestek, Inc.
Thermal Solutions LLC.
<Insert manufacturer's name>.
B.
Description: Factory-fabricated, -assembled, and -tested boiler, with tubes sealed into headers
pressure tight, and set on a steel base; including jacket, flue-gas vent connections, combustionair-intake connections, water supply and return connections, and controls.
C.
Heat Exchanger:
1.
2.
3.
4.
Finned copper tubing with stainless-steel baffles.
Cast-iron headers, glass-lined.
Two-pass, horizontal configuration.
Tubes shall be sealed in header by mechanically rolling tubes in header.
D.
Combustion Chamber Internal Insulation: Interlocking panels of refractory insulation, hightemperature cements, mineral fiber, and ceramic refractory tile for service temperatures of up to
2,000 deg F (1100 deg C).
E.
Casing:
1.
2.
3.
4.
5.
6.
F.
Jacket: Sheet metal, with snap-in, mechanically fastened, and/or interlocking closures.
Control Compartment Enclosure: Integral to boiler jacket.
Finish: Thermal set powder coat paint with textured finish.
Insulation: Minimum 1-inch- (25-mm-) thick, mineral-fiber insulation surrounding the
heat exchanger.
Combustion-Air Connection: Inlet air duct collar.
Mounting base to secure boiler.
Burner:
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1.
Burner Tubes: Stainless steel, for [natural] [propane] gas.
a.
b.
c.
2.
3.
4.
G.
Gas Train: Control devices and [low/high/low] control sequence shall comply with CSA
requirements. In addition to these requirements, include shutoff cock, pressure regulator,
and control valve.
Gas Train: Multiple combination gas valves with manual shutoff.
Ignition: Proven hot surface ignition.
Hot-Water Boiler Trim:
1.
2.
3.
4.
5.
6.
7.
8.
Hot-Water Temperature Controllers: Operating[, firing rate,] and manual reset high
limit.
Safety Relief Valve: 75 psig (517 kPa) ASME rated.
Pressure and Temperature Gage: Minimum 3-1/2-inch- (89-mm-) diameter, combination
water-pressure and -temperature gage. in compliance with ASME pressure vessel code.
Burner site glass.
On/off toggle switch.
Air intake filter.
Drain Valve: Minimum NPS 3/4 (DN 20) hose-end valve.
Options:
a.
b.
c.
d.
e.
f.
g.
h.
H.
Direct Vent: Factory-mounted centrifugal fan to draw outside air into boiler and
discharge flue gases into boiler vent.
Burner shall have a viewing port for observation of burner operation.
Boiler control will prepurge and postpurge the combustion chamber before firing.
Cupronickel heat exchanger tubes.
Bronze trim.
Alarm bell with dry contacts, red trouble light, and green main gas light.
200 deg F (93 deg C) high limit.
Boiler pump.
Low water cutoff with manual reset and test button.
ASME CSD-1.
Reversed water connections.
Controls:
1.
Boiler operating controls shall include the following devices and features:
a.
b.
c.
d.
e.
2.
Control transformer.
Set-Point Adjust: Set points shall be adjustable.
Sequence of Operation: Call for heat, prepurge, ignitor warmup, ignitor prove,
main gas ignition, main gas proof, end of call for heat, and post purge.
Connections for external staging control with selector switch that allows user to
choose between on board control or external staging control.
Pump time delay.
Burner Operating Controls: To maintain safe operating conditions, burner safety controls
limit burner operation.
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a.
b.
c.
d.
e.
I.
High Cutoff: Manual reset stops burner if operating conditions rise above
maximum boiler design temperature.
Connections for external staging control with selector switch that allows user to
choose between on board control or external staging control.
Water Flow Switch: Automatic-reset paddle-switch shall prevent burner operation
on low water flow.
Blocked Vent Safety Switch: Manual-reset switch factory mounted on draft
diverter.
Rollout Safety Switch: Factory mounted on boiler combustion chamber.
Capacities and Characteristics:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Heating Medium: Hot water.
Design Pressure and Temperature Rating: [160 psig (1100 kPa), 250 deg F (120 deg C)]
<Insert values>.
Safety Relief Valve Setting: 75 psig (517 kPa) <Insert psig (kPa)>.
Entering-Water Temperature: Minimum 120 deg F (49 deg C) <Insert deg F (deg C)>.
Leaving-Water Temperature: Maximum 240 deg F (116 deg C) <Insert deg F (deg C)>.
Design Water-Flow Rate: [34 gpm (2.15 L/s)] [51 gpm (3.22 L/s)] [68 gpm (4.29 L/s)]
[85 gpm (5.36 L/s)] [102 gpm (6.44 L/s)] [119 gpm (7.51 L/s)] [136 gpm (8.58 L/s)].
<Insert gpm (L/s)>.
Design Pressure Drop: [1.1 feet (3.31 kPa)] [2.3 feet (6.89 kPa)] [3.6 feet (10.7 kPa)]
[6.1 feet (18.2 kPa)] [7.2 feet (21.5 kPa)] [10.5 feet (31.4 kPa)] [12.5 feet (37.4 kPa)].
<Insert feet (kPa)>.
AHRI Certified Thermal Efficiency: [85.0] [85.2] <Insert number> percent.
AHRI Certified Combustion Efficiency: [85.0] [85.1] <Insert number> percent.
NOx Emissions: Less than 10 ppm, adjusted to 3 percent O2.
Number of Passes: Two.
Gas Input: [500 Mbh (146 kW)] [750 Mbh (220 kW)] [999 Mbh (293 kW)] [1,250
Mbh (366 kW)] [1,500 Mbh (439 kW)] [1,750 Mbh (512 kW)] [1,999 Mbh (583 kW)]
<Insert Mbh (kW)>.
Gas Pressure: 4- to 13-in. wg (995 to 3235 Pa).
Electrical Characteristics:
a.
b.
c.
d.
Volts: 115-V ac.
Phase: Single.
Hertz: 60 hz.
Minimum Circuit Ampacity: 15-A.
FINNED WATER-TUBE BOILERS (500 – 2,000 MBH)
2.4
A.
Basis-of-Design Product: Subject to compliance with requirements, provide Laars Heating
Systems Company; Pennant, or comparable product by one of the following:
1.
2.
3.
4.
Raypak, Inc.
RBI; A Division of Mestek, Inc.
Thermal Solutions LLC.
<Insert manufacturer's name>.
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B.
Description: Factory-fabricated, -assembled, and -tested boiler, with tubes sealed into headers
pressure tight, and set on a steel base; including jacket, flue-gas vent connections, combustionair-intake connections, water supply and return connections, and controls.
C.
Heat Exchanger:
1.
2.
3.
4.
Finned copper tubing with stainless-steel baffles.
Cast-iron headers, glass-lined.
Two-pass, horizontal configuration.
Tubes shall be sealed in header by mechanically rolling tubes in header.
D.
Combustion Chamber Internal Insulation: Interlocking panels of refractory insulation, hightemperature cements, mineral fiber, and ceramic refractory tile for service temperatures of up to
2,000 deg F (1100 deg C).
E.
Casing:
1.
2.
3.
4.
5.
6.
7.
F.
Jacket: Sheet metal, with snap-in, mechanically fastened, and/or interlocking closures.
Control Compartment Enclosure: Integral to boiler jacket.
Finish: Thermal set powder coat paint with textured finish.
Insulation: Minimum 1-inch- (25-mm-) thick, mineral-fiber insulation surrounding the
heat exchanger.
Combustion-Air Connection: Inlet air duct collar that is field configurable for either top
or back connection.
Combustion-Vent Connection: Exhaust vent collar that is field configurable for either top
or back connection.
Mounting base to secure boiler.
Burner:
1.
Burner Tubes: Stainless steel, for [natural] [propane] gas.
a.
b.
c.
2.
3.
4.
5.
6.
G.
Direct Vent: Factory-mounted centrifugal fan to draw outside air into boiler and
discharge flue gases into boiler vent.
Burner shall have a viewing port for observation of burner operation.
Boiler control will prepurge and postpurge the combustion chamber before firing.
Gas Train: Control devices and staging control sequence shall comply with CSA
requirements. In addition to these requirements, include shutoff cock, pressure regulator,
and control valve.
Firing Rates: Models PNCH 0500 and 0750 are two stage. Model PNCH 1000 is three
stage. Models PNCH 1250 – 2000 are four stage.
Firing Rates: Models PNCH 0500– 2000 are on/off.
Gas Train: Multiple combination gas valves with manual shutoff.
Ignition: Proven hot surface ignition.
Hot-Water Boiler Trim:
1.
2.
Hot-Water Temperature Controllers: Operating, electronic PID with six application
modes [, firing rate,] and high limit.
Hot-Water Temperature Controllers: Operating, electronic PI and high limit.
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3.
4.
5.
6.
7.
8.
The boiler shall be built with an automatic mixing (anti-condensing) system, to protect
the heat exchanger from excessive condensation due to low return water temperature,
associated with low temperature systems down to 70 deg F (21 deg C).
Safety Relief Valve: ASME rated.
Pressure and Temperature Gage: Minimum 3-1/2-inch- (89-mm-) diameter, combination
water-pressure and -temperature gage. in compliance with ASME pressure vessel code.
Drain Valve: Minimum NPS 3/4 (DN 20) hose-end valve.
Mounted boiler pump.
Options:
a.
b.
c.
d.
e.
f.
g.
H.
Controls:
1.
Boiler operating controls shall include the following devices and features:
a.
Electronic PID temperature control with six application modes.
b.
Set-Point Adjust: Set points shall be adjustable.
c.
Diagnostic lights and test points for low water, blocked flue and low air flow.
d.
Connections for external staging control with selector switch that allows user to
choose between on board control or external staging control.
e.
Electronic PI temperature and anti-condensing control
f.
Set-Point Adjust: Set points shall be adjustable.
g.
Diagnostic lights for power on, call for heat, pump on, main valve, and service.
h.
Control transformer.
i.
Dry alarm contacts for ignition failure.
j.
Sequence of Operation: Call for heat, prepurge, ignitor warmup, ignitor prove,
main gas ignition, main gas proof, end of call for heat, and post purge.
2.
Burner Operating Controls: To maintain safe operating conditions, burner safety controls
limit burner operation.
a.
b.
c.
d.
I.
Cupronickel heat exchanger tubes.
Boiler pump.
Low water cutoff with manual reset and test button.
ASME CSD-1.
Reversed water connections.
Bronze trim.
200 deg F (93 deg C) high limit.
High Cutoff: Manual reset stops burner if operating conditions rise above
maximum boiler design temperature.
Water Flow Switch: Automatic-reset paddle-switch shall prevent burner operation
on low water flow.
Blocked Vent Safety Switch: Manual-reset switch factory mounted on draft
diverter.
Rollout Safety Switch: Factory mounted on boiler combustion chamber.
Capacities and Characteristics:
1.
2.
3.
Heating Medium: Hot water.
Design Pressure and Temperature Rating: [160 psig (1100 kPa), 250 deg F (120 deg C)]
<Insert values>.
Safety Relief Valve Setting: 75 psig (517 kPa) <Insert psig (kPa)>.
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4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
Entering-Water Temperature: Minimum 70 deg F (21 deg C) <Insert deg F (deg C)>.
Entering-Water Temperature: Minimum 120 deg F (49 deg C) <Insert deg F (deg C)>.
Leaving-Water Temperature: Maximum 240 deg F (116 deg C) <Insert deg F (deg C)>.
Design Water-Flow Rate: [34 gpm (2.15 L/s)] [51 gpm (3.22 L/s)] [68 gpm (4.29 L/s)]
[85 gpm (5.36 L/s)] [102 gpm (6.44 L/s)] [119 gpm (7.51 L/s)] [136 gpm (8.58 L/s)].
<Insert gpm (L/s)>.
Design Pressure Drop: [1.1 feet (3.31 kPa)] [2.3 feet (6.89 kPa)] [3.6 feet (10.7 kPa)]
[6.1 feet (18.2 kPa)] [7.2 feet (21.5 kPa)] [10.5 feet (31.4 kPa)] [12.5 feet (37.4 kPa)].
<Insert feet (kPa)>.
AHRI Certified Thermal Efficiency: [85.0] [85.2] <Insert number> percent.
AHRI Certified Combustion Efficiency: [85.0] [85.1] <Insert number> percent.
NOx Emissions: Less than 10 ppm, adjusted to 3 percent O2.
Number of Passes: Two.
Gas Input: [500 Mbh (146 kW)] [750 Mbh (220 kW)] [999 Mbh (293 kW)] [1,250
Mbh (366 kW)] [1,500 Mbh (439 kW)] [1,750 Mbh (512 kW)] [1,999 Mbh (583 kW)]
<Insert Mbh (kW)>.
Gas Pressure: 4- to 13-in. wg (995 to 3235 Pa).
Electrical Characteristics:
a.
b.
c.
d.
Volts: 115-V ac.
Phase: Single.
Hertz: 60 hz.
Minimum Circuit Ampacity: 15-A.
FINNED WATER-TUBE BOILERS (1,200 – 2,400 MBH)
2.5
A.
Basis-of-Design Product: Subject to compliance with requirements, provide Laars Heating
Systems Company; Rheos model RHCH or comparable product by one of the following:
1.
2.
3.
4.
Raypak, Inc.
RBI; A Division of Mestek, Inc.
Thermal Solutions LLC.
<Insert manufacturer's name>.
B.
Description: Factory-fabricated, -assembled, and -tested boiler, with tubes sealed into headers
pressure tight, and set on a steel base; including jacket, flue-gas vent connections, combustionair-intake connections, water supply and return connections, and controls.
C.
Heat Exchanger:
1.
2.
3.
4.
Finned copper tubing with stainless-steel baffles.
Steel headers, glass-lined.
Two-pass, coil configuration.
Tubes shall be sealed in header by mechanically rolling tubes in header.
D.
Combustion Chamber Internal Insulation: High-temperature cements, mineral fiber, and
ceramic refractory tile for service temperatures of up to 2,000 deg F (1100 deg C).
E.
Casing:
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1.
2.
3.
4.
5.
F.
Jacket: Sheet metal, with snap-in, mechanically fastened, and/or interlocking closures.
Control Compartment Enclosure: Integral to boiler jacket.
Finish: Thermal set powder coat paint with textured finish.
Combustion-Air Connection: Inlet air duct collar.
Mounting base to secure boiler.
Burner:
1.
Burner shall be vertical, stainless steel, and integral to boiler, for [natural] [propane]
gas.
a.
b.
c.
2.
3.
4.
G.
Gas Train: Control devices and [full-modulation] [on/off] [low/high/low]
[proportional] control sequence shall comply with CSA requirements. In addition to
these requirements, include shutoff cock, pressure regulator, and control valve.
Gas Train: Combination gas valve with manual shutoff,
Ignition: Proven hot surface ignition that keeps the boiler in low fire at the start of each
cycle. Ignition system shall have 100 percent main-valve shutoff with electronic
supervision of burner flame.
Hot-Water Boiler Trim:
1.
2.
3.
4.
5.
6.
Hot-Water Temperature Controllers: Operating[, firing rate,] and high limit.
Safety Relief Valve: ASME rated.
Pressure and Temperature Gage: Minimum 3-1/2-inch- (89-mm-) diameter, combination
water-pressure and -temperature gage in compliance with ASME pressure vessel code.
Boiler Air Vent: Manual.
Drain Valve: Minimum NPS 3/4 (DN 20) hose-end valve.
Options:
a.
b.
c.
d.
H.
Sealed Combustion: Factory-mounted centrifugal fan to draw outside air into
boiler and discharge into burner compartment.
Burner shall have a viewing port for observation of burner operation.
Boiler control will prepurge and postpurge the combustion chamber before firing.
Cupronickel heat exchanger tubes.
Alarm bell.
200 deg F (93 deg C) high limits.
Boiler pump.
Controls:
1.
Boiler operating controls shall include the following devices and features:
a.
b.
c.
2.
Control transformer.
Set-Point Adjust: Set points shall be adjustable.
Sequence of Operation: Call for heat, prepurge, ignitor warmup, ignitor prove,
main gas ignition, main gas proof, modulate blower and gas input based on
controller settings 50 to 100 percent of full fire, end of call for heat, post-purge.
Burner Operating Controls: To maintain safe operating conditions, burner safety controls
limit burner operation.
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a.
b.
c.
d.
e.
f.
g.
h.
i.
j.
k.
l.
m.
n.
I.
Temperature Control: Adjustable electronic PI.
High Cutoff: Manual reset stops burner if operating conditions rise above
maximum boiler design temperature.
Water Flow Switch: Automatic-reset paddle-switch shall prevent burner operation
on low water flow.
Low water cutoff with manual reset and test button.
Blocked Vent Safety Switch: Manual-reset switch factory mounted on draft
diverter.
Rollout Safety Switch: Factory mounted on boiler combustion chamber.
High gas pressure switch: To ensure gas pressure to burner does not exceed
allowable parameters
Low gas pressure switch: To ensure gas pressure to boiler is high enough to serve
the boiler.
ASME CSD-1 compliant.
Leak test valve.
Manual firing valve.
Indicator lights: For status of power, call for heat, pre-purge, burner on, and
ignition failure.
Dry alarm contacts for ignition failure.
Selector switch: To choose between internal control and external 0-10 V dc
modulation control signal.
Capacities and Characteristics:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Heating Medium: Hot water.
Design Pressure and Temperature Rating: [160 psig (1100 kPa), 250 deg F (120 deg C)]
<Insert values>.
Safety Relief Valve Setting: 75 psig (517 kPa) <Insert psig (kPa)>.
Entering-Water Temperature: Minimum 130 deg F (54 deg C) <Insert deg F (deg C)>.
Leaving-Water Temperature: Maximum 240 deg F (116 deg C) <Insert deg F (deg C)>.
Design Water-Flow Rate: [83 gpm (5.24 L/s)] [113 gpm (7.13 L/s)] [138 gpm (8.71
L/s)] [165 gpm (10.4 L/s)] <Insert gpm (L/s)>.
Design Pressure Drop: [12.0 feet (35.9 kPa)] [14.0 feet (41.8 kPa)] [13.0 feet (38.9
kPa)] [12.0 feet (35.9 kPa)] <Insert feet (kPa)>.
AHRI Certified Thermal Efficiency: [86.0] [86.3] [86.7] [86.9] percent.
AHRI Certified Combustion Efficiency: [86.4] [86.0] [85.7] [85.5] percent.
NOx Emissions: Less than 10 ppm, adjusted to 3 percent O2.
Number of Passes: Two.
Gas Input: [1,200 Mbh (352 kW)] [1,600 Mbh (469 kW)] [2,000 Mbh (586 kW)]
[2,400 Mbh (703 kW)] <Insert Mbh (kW)>.
Gas Pressure: 4- to 13-in. wg (995 to 3235 Pa).
Electrical Characteristics:
a.
b.
c.
d.
Volts: 115-V ac.
Phase: Single.
Hertz: 60 hz.
Minimum Circuit Ampacity: 15-A.
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2.6
ELECTRICAL POWER
A.
Single-Point Field Power Connection: Factory-installed and -wired switches, motor controllers,
transformers, and other electrical devices necessary shall provide a single-point field power
connection to boiler.
1.
Enclosure: NEMA 250, Type [1] <Insert type>.
a.
b.
c.
2.
3.
4.
5.
6.
7.
2.7
Enclosure shall have integral vents, fans, heat, and air conditioner as required to
automatically control temperature inside enclosure within safe operating limits of
devices installed within the enclosure.
Mounted on boiler assembly at a location convenient to operator.
Enclosure shall have hinged full-size door with key lock with common key for all
locks.
Wiring shall be numbered and color-coded to match wiring diagram.[ Provide a
laminated wiring diagram located inside enclosure.]
Install factory wiring outside of an enclosure in a [metal ]raceway. Make final
connections to motors using flexible conduit. Provide watertight installation for
applications exposed to moisture.
Field power interface shall be to [fused disconnect switch] [nonfused disconnect
switch] [circuit breaker]. Withstanding rating of disconnecting means shall protect
equipment. Coordinate requirements with field electrical power source.
Provide branch power circuit to each motor and to controls[ with disconnect switch or
circuit breaker].
Provide each motor with NEMA-rated motor controller, hand-off-auto switch, and
overcurrent protection. Provide variable-frequency controller with manual bypass and
line reactors for each variable-speed motor indicated.
Provide transformer with fuses and power wiring to power a 20-A 120-V ac duplex
receptacle mounted in each boiler control panel for use in connecting analytical and
testing equipment.
SOURCE QUALITY CONTROL
A.
Test and inspect factory-assembled boilers, before shipping, according to latest edition of the
ASME Boiler and Pressure Vessel Code.
B.
Burner and Hydrostatic Test:
1.
2.
C.
Factory adjust burner to eliminate excess oxygen, carbon dioxide, oxides of nitrogen
emissions, and carbon monoxide in flue gas and to achieve performance requirements
indicated.
Perform hydrostatic test of pressure vessel, piping, and trim of assembled boiler.
Witness Testing:
1.
2.
Allow Owner access to witness source quality-control testing of boilers.
Notify [Architect] [Owner] [15] <Insert number> days in advance of testing.
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PART 3 - EXECUTION
3.1
EXAMINATION
A.
Before boiler installation, examine roughing-in for concrete equipment bases, anchor-bolt sizes
and locations, and flue; piping; controls; and electrical connections to verify actual locations,
sizes, and other conditions affecting boiler performance, maintenance, and operations.
1.
Boiler locations indicated on Drawings are approximate. Determine exact locations
before roughing-in for flue, piping, controls, and electrical connections.
B.
Examine areas where boilers will be installed for suitable conditions.
C.
Proceed with installation only after unsatisfactory conditions have been corrected.
3.2
BOILER INSTALLATION
A.
Coordinate size and location of bases. Cast anchor-bolt inserts into concrete bases. Concrete,
reinforcement, and formwork requirements are specified with concrete.
B.
Equipment Mounting:
1.
2.
3.
Install boilers on cast-in-place concrete equipment base(s). Comply with requirements for
equipment bases and foundations specified in [Section 033000 "Cast-in-Place
Concrete."] [Section 033053 "Miscellaneous Cast-in-Place Concrete."]
Comply with requirements for vibration isolation and seismic-control devices specified in
Section 230548 "Vibration and Seismic Controls for HVAC."
Comply with requirements for vibration isolation devices specified in Section 230548.13
"Vibration Controls for HVAC."
C.
Install gas-fired boilers according to NFPA 54.
D.
Assemble and install boiler trim, components, and accessories that are not factory installed.
E.
Install control and electrical devices furnished with boiler that are not factory mounted.
F.
Install control and power wiring to field-mounted control and electrical devices furnished with
boiler that are not factory installed.
G.
Perform boil-out and cleaning procedures according to manufacturer's written instructions after
completion of hydrostatic testing and before performing other field tests.[ Boiler
manufacturer's factory-authorized representative shall witness boil-out and cleaning
procedures.] Following boil-out and cleaning procedures, boiler shall be washed and flushed
until water leaving boiler is clear.
H.
Protect boiler fireside and waterside from corrosion.
1.
Before boiler is filled with water, protect by dry storage method recommended by boiler
manufacturer.
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2.
3.
3.3
After boiler is filled with water, and left not fired for more than [10] <Insert number>
days, protect by wet storage method recommended by boiler manufacturer.
Chemical Treatment: Quality of water in boilers shall be maintained by a professional
water-treatment organization that shall provide on-site supervision to maintain the
required water quality during periods of boiler storage as well as during operating,
standby, and test conditions. Refer to <Insert applicable Section number and title> for
additional requirements.
PIPING CONNECTIONS
A.
Piping installation requirements are specified in other Sections. Drawings indicate general
arrangement of piping, fittings, and specialties.
B.
Where installing piping adjacent to boiler(s), allow space for service and maintenance.
C.
Connect gas piping to boiler gas-train inlet with dirt leg, shutoff valve, and union or flange.
Piping shall be at least full size of gas-train connection. Provide a reducer if required.
D.
Connect hot-water piping to supply- and return-boiler connections with shutoff valve and union
or flange at each connection.
E.
Install piping from safety relief valves to nearest floor drain.
F.
Install piping from safety valves and drip-pan elbows. Extend piping from safety valves and
terminate to vent outdoors, where required by local jurisdiction. Extend piping from drip-pan
elbow drain to nearest floor drain.
G.
Install piping from equipment drain connection to nearest floor drain. Piping shall be at least
full size of connection. Provide an isolation valve if required.
H.
Hot equipment drains connected to sanitary drainage system shall be cooled before discharging
into the system if required to comply with more stringent of governing code requirements and
requirements indicated.
1.
I.
3.4
Provide a temperature-controlled nonpotable domestic cold water source to cool hot
equipment drains to deliver a discharge temperature of <Insert temperature>.
Connect chemical-treatment piping to each boiler chemical-treatment connection with check
valve and isolation valve.
FLUE CONNECTIONS
A.
Boiler Flue Venting:
1.
2.
Install venting kit and combustion-air intake.
Connect full size to boiler connections. Comply with requirements in Section 235123
"Gas Vents."
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B.
Connect breeching to full size of boiler outlet. Comply with requirements in [Section 235116
"Fabricated Breechings and Accessories"] [and] [Section 235133 "Insulated Sectional
Chimneys"] for venting materials.
C.
Install easily accessible test ports for field testing of flue gas from each boiler.
3.5
ELECTRICAL POWER CONNECTIONS
A.
Connect wiring according to Section 260519 "Low-Voltage Electrical Power Conductors and
Cables."
B.
Ground equipment according to Section 260526 "Grounding and Bonding for Electrical
Systems."
3.6
CONTROLS CONNECTIONS
A.
Install control and electrical power wiring to field-mounted control devices.
B.
Connect control wiring between boilers and other equipment to interlock operation as required,
to provide a complete and functioning system.
C.
Connect control wiring between boiler control interface and [DDC control system] <Insert
system description> for remote monitoring and control of boilers. Comply with requirements
in [Section 230923 "Direct Digital Control (DDC) System for HVAC"] <Insert Section
number and title>.
3.7
FIELD QUALITY CONTROL
A.
Testing Agency: [Owner will engage] [Engage] a qualified testing agency to perform tests and
inspections.
B.
Manufacturer's Field Service: Engage a factory-authorized service representative to test and
inspect components, assemblies, and equipment installations, including connections.
C.
Perform the following tests and inspections[ with the assistance of a factory-authorized
service representative]:
1.
2.
3.
4.
Perform installation and startup checks according to manufacturer's written instructions.
Hydrostatic Leak Test: Repair leaks and retest until no leaks exist.
Operational Test: Start units to confirm proper motor rotation and unit operation. Adjust
air-fuel ratio and combustion.
Test and adjust controls and safeties. Replace damaged and malfunctioning controls and
equipment.
a.
Burner Test: Adjust burner to eliminate excess oxygen, carbon dioxide, oxides of
nitrogen emissions, and carbon monoxide in flue gas and to achieve combustion
efficiency.
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b.
c.
Check and adjust initial operating set points and high- and low-limit safety set
points of fuel supply, water level, and water temperature.
Set field-adjustable switches and circuit-breaker trip ranges as indicated.
D.
Boiler will be considered defective if it does not pass tests and inspections.
E.
Prepare test and inspection reports.
F.
Occupancy Adjustments: When requested within [12 months of date of Substantial
Completion] <Insert time period>, provide on-site assistance in adjusting system to suit actual
occupied conditions. Provide up to [two] <Insert number> visits to Project during other-thannormal occupancy hours for this purpose.
G.
Performance Tests:
1.
2.
3.
Manufacturer's Field Service: Engage a factory-authorized service representative to
inspect component assemblies and equipment installations, including connections, and to
conduct performance testing.
Boilers shall comply with performance requirements indicated, as determined by fieldperformance tests. Adjust, modify, or replace equipment in order to comply.
Perform field-performance tests to determine the capacity and efficiency of the boilers.
a.
b.
c.
4.
5.
6.
7.
8.
9.
10.
3.8
For dual-fuel boilers, perform tests for each fuel.
Test for full capacity.
Test for boiler efficiency at full capacity. Determine and document efficiency at
each test point.
Test each safety valve. Record pressure at valve blowdown and reset. Test valve(s) with
boiler operating at full capacity to ensure valve has capacity to prevent further rise in
pressure.
For boilers equipped with automatic oxygen trim control, conduct tests with automatic
oxygen trim control on manual at zero trim and record performance. Repeat tests with
automatic oxygen trim control under automatic control and record performance.
Repeat tests until results comply with requirements indicated.
Provide measurement and analysis equipment required to determine performance.
Provide temporary equipment and system modifications necessary to dissipate the heat
produced during tests if building systems are inadequate.
Notify [Architect] [Owner] [20] <Insert number> days in advance of test dates.
Document test results in a report and submit with informational submittals.
DEMONSTRATION
A.
[Engage a factory-authorized service representative to train] [Train] Owner's maintenance
personnel to adjust, operate, and maintain boilers.[ Video training sessions and provide
electronic copy of video to Owner.] Refer to Section 017900 "Demonstration and Training."
END OF SECTION 235233
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