2. The boiler(s) shall be CSA tested and certified with a minimum thermal efficiency of 94 percent
at full fire.
3. The boiler(s) shall be ASME inspected and stamped and National Board registered for 160
PSIG maximum allowable working pressure and 210ºF maximum allowable temperature,
complete with a Manufacturer's Data Report.
4. The boiler(s) shall have a floor loading of 95 lbs./square foot or less.
B. Primary Heat Exchanger
1. The primary heat exchanger shall be of a helically wound, multi-pass
completely encircle the combustion chamber for maximum efficiency.
2. There shall be no banding material, bolts, gaskets or "O" rings in the header configuration. The
heat exchanger is removable from the cabinet for replacement without removing the entire
boiler assembly from the site. The stainless steel combustion chamber shall be designed to
have a trough located on the bottom front and back section leading to the middle to ensure
that condensation does not collect in the boiler.
3. The low water volume primary heat exchanger shall be explosion-proof on the water side and
shall carry a twenty-five-year warranty against thermal shock.
4. The flue connection, combustion air opening, gas connection, electrical connections and
condensate drain shall be located on the rear. Water connections shall be located on the left
rear top of the unit.
C. Condensate Drain
1. The boiler(s) will feature a condensate drain sensor which will shut down the boiler(s) if the
condensate drain is blocked.
D. Burners
1. The combustion chamber shall be of the sealed combustion type employing the Raypak high
temperature metal fiber burner, mounted in a horizontal orientation.
2. The burner shall be a premix design and constructed of high grade Inconel and must be
capable of firing at both a complete blue flame with maximum gas and air input as well as
firing infrared when gas and air are reduced. The burner must be capable of firing at 100% of
rated input when supplied with 4.0” WC of inlet gas pressure, so as to maintain service under
heavy demand conditions; no exceptions.
3. The burner shall use a combustion air blower to precisely control the fuel/air mixture for
maximum efficiency throughout the entire range of modulation. The combustion air blower
shall operate for a pre-purge period before burner ignition and a post-purge period after burner
operation to clear the combustion chamber.
4. The blower shall infinitely vary its output in response to a PWM signal supplied directly from
the integrated modulating control, thereby electronically and precisely adjusting the volume of
air and gas supplied for combustion. Minimum fire shall be 20 percent of rated input.
E. Pilot Control System
1. The boiler(s) shall be equipped with a 100 percent safety shutdown.
2. The ignition shall be spark ignition type with full flame rectification by the ignition source, with a
four try-for-ignition sequence, to ensure consistent operation.
3. The igniter will be located above the burner to ensure easy ignition.
gas at a rated input of BTU/hr.
design and shall
Project Name / Date Division 23 52 33.13 - 2
Page 3
4. The ignition control module shall include an LCD display that indicates individual diagnostic
faults.
5. A viewing port shall be provided, permitting visual observation of burner operation.
F. Gas Train
1. The boiler(s) shall have a firing/leak test valve and pressure test valve as required by CSD-1.
2. The boiler(s) shall have dual-seated main gas valve.
3. Gas control trains shall have a redundant safety shut-off feature, main gas regulation, and
plugged pressure tapping to meet the requirements of ANSI Z21.13/CSA 4.9.
G. Boiler Control
1. The following safety controls shall be provided:
a. High limit control with manual reset
b. Flow switch, mounted and wired
c.
PSIG ASME pressure relief valve, piped by the installer to an approved drain
d. Temperature and pressure gauge (shipped loose)
2. The boiler(s) shall be equipped with an integrated PID modulating temperature controller with
LCD display that incorporates an adjustable energy-saving pump control relay and freeze
protection and is factory mounted and wired to improve system efficiency; three water sensors
included (system sensor is loose).
3. The boiler(s) shall also be equipped with password security, outdoor reset, pump exercise and
a PC connection. The boiler shall allow for 0-10 VDC input connection for remote building
DDC system control and have built-in “Cascade” to sequence and rotate while maintaining
modulation of up to eight boilers without utilizing an external sequencer.
H. Firing Mode: Provide electronic modulating control of the gas input to the boiler.
I. Boiler Diagnostics
1. Provide internal circuit board indicating the following safety faults by a 2 line, 20 character,
LCD display:
a. System status
b. Condensate blockage
c. Manual reset high limit
d. Auto reset high limit
e. Blocked vent
f. Low gas pressure switch (optional)
g. High gas pressure switch (optional)
h. Controller alarm
i. Flow switch
j. Sensor failure
k. High vent temperature
l. Ignition lock-out
J. Cabinet
1. The corrosion-resistant galvanized-steel jackets shall be finished with a baked-on epoxy
powder coat, which is suitable for outdoor installation, applied prior to assembly for complete
coverage.
2. The boiler(s), if located on a combustible floor, shall not require a separate combustible floor
base.
3. The boiler(s) shall connect both the combustion air and flue products through the back of the
unit.
4. The heater shall have as standard an internal, combustion air filter rated to MERV 8 (>95%
arrestance).
K. Boiler Pump – The boiler(s) shall be equipped with an optional factory-packaged pump system.
Project Name / Date Division 23 52 33.13 - 3
Page 4
2.3 BOILER OPERATING CONTROLS
A. Each boiler shall have the ability to receive a 0 to 10 VDC signal from the Central Energy
Management and Direct Digital Control System (EMCS) to vary the setpoint and enable/disable.
Each boiler shall have an alarm contact for connection to the central EMCS system.
B. Each boiler shall be equipped with Modbus communications compatibility.
C. The boiler(s) shall feature an integrated modulating digital controller with selectable outdoor reset
mode option, mounted and wired.
D. System sensor and optional air temperature sensor shall be shipped loose for field installation by
installing contractor. Inlet/Outlet sensors are factory-installed.
2.4 DIRECT VENT
A. The boiler(s) shall meet safety standards for direct vent equipment as noted by the 2006 Uniform
Mechanical Code, section 1107.6, and ASHRAE 15-1994, section 8.13.6.
B. The boiler shall be capable of combined combustion air duct and vent lengths not to exceed 200
equivalent feet.
2.5 SOURCE QUALITY CONTROL
A. The boiler(s) shall be completely assembled, wired, and fire-tested prior to shipment from the
factory.
B. The boiler(s) shall be furnished with the sales order, ASME Manufacturer’s Data Report(s),
inspection sheet, wiring diagram, rating plate and Installation and Operating Manual.
PART 3 - EXECUTION
3.1 INSTALLATION
A. Must comply with:
1. Local, state, provincial, and national codes, laws, regulations and ordinances
2. National Fuel Gas Code, ANSI Z223.1/NFPA 54 – latest edition
3. National Electrical Code, ANSI/NFPA 70 – latest edition
4. Standard for Controls and Safety Devices for Automatically Fired Boilers, ANSI/ASME CSD-1,
when required
5. Canada only: CAN/CGA B149 Installation Code and CSA C22.1 CEC Part I
6. Manufacturer’s installation instructions, including required service clearances and venting
guidelines
B. Manufacturer’s representative to verify proper and complete installation.
3.2 START-UP
A. Shall be performed by Raypak factory-trained personnel.
B. Test during operation and adjust if necessary:
1. Safeties
2. Operating Controls
3. Static and full load gas supply pressure
4. Gas manifold and blower suction pressure
5. Combustion analysis
C. Submit copy of start-up report to Architect and Engineer.
3.3 TRAINING
A. Provide factory-authorized service representative to train maintenance personnel on procedures
and schedules related to start-up, shut-down, troubleshooting, servicing, and preventive
maintenance.
B. Schedule training at least seven days in advance.
END OF SECTION
Project Name / Date Division 23 52 33.13 - 4
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