Copyright 2001 AIA
MASTERSPEC - OUTLINE
12/01
SECTION 15562 - INDIRECT-FIRED H&V UNITS
1.1
SUMMARY
A.
1.2
Factory-assembled, prewired, self-contained, indirect-fired, [gas] [oil] furnace H&V units[ with
an evaporative cooling package,] installed [outside] [inside] the building.
WARRANTY
A.
1.3
Materials and Workmanship: [Five] [10] <Insert number> years for heat exchangers.
COMPONENTS
A.
Cabinet: [Single] [Double]-wall galvanized-steel panels.[ Cabinet shall be fully weatherized
for outside installation.]
1.
2.
3.
4.
B.
Access Panels: [Lift-out] [Piano hinged with cam-lock fasteners].
Internal Insulation: [Complete unit] [Furnace and fan sections only], [1 inch (25
mm)] [2 inches (50 mm)] thick.
Discharge: [Horizontal] [Vertical] pattern.
Roof Curb: [16 inches (400 mm)] <Insert dimension> high.
Supply-Air Fan: Centrifugal type, with heavy-duty[, self-aligning, permanently lubricated
ball bearings] [, pillow-block bearings rated for L50 or 200,000 hours with external grease
fittings].
1.
2.
Motor: [Open dripproof] [Totally enclosed], single-speed motor.
Mounting: In fan casing with [restrained,] [elastomeric] [spring] isolators.
C.
Outdoor-air hood.
D.
Air Filters: [1-inch- (25-mm-)] [2-inch- (50-mm-)] thick, [cleanable] [disposable-panel]
type.
E.
Dampers: Outdoor air[ and return air].
F.
Indirect-Fired Gas Furnace:
1.
Burners: [Aluminized steel with stainless-steel inserts] [Stainless steel].
a.
b.
c.
d.
e.
2.
3.
Gas Control Valve: [Single stage] [Two stage] [Modulating].
Fuel: [Natural] [Propane] gas.
Minimum Thermal Efficiency: 80 percent.
Ignition: Electronically controlled electric spark with flame sensor.
High-Altitude [Model] [Kit]: For Project elevation above sea level.
Venting: [Gravity] [Power].
Combustion-air intake.
INDIRECT-FIRED H&V UNITS
15562 - 1
Copyright 2001 AIA
4.
5.
12/01
Heat Exchanger: [Aluminized] [Stainless] steel.
Safety Controls:
a.
b.
c.
d.
e.
f.
g.
h.
i.
G.
MASTERSPEC - OUTLINE
Vent Flow Verification: [Differential pressure switch to verify open vent]
[Flame rollout switch].
Control transformer.
High Limit: Thermal switch or fuse to stop burner.
Gas Train: Gas valve assembly containing pilot solenoid valve, [hydraulic]
[electronic]-modulating temperature control valve, pilot filter, pressure regulator,
pilot shutoff, and manual shutoff all in one body.
Purge-period timer.
Gas Manifold: Safety switches and controls to comply with ANSI standards [and]
[FMG] [IRI].
Airflow proving switch.
Automatic-reset, high-limit control device.
Safety lockout switch.
Indirect-Fired Oil Furnace:
1.
2.
Heat Exchanger: Welded, [stainless ]steel.
Oil Burner: Flame-retention, pressure-atomizing, forced-draft, gun type with integrated
fuel pump and electronic-spark ignition.
a.
b.
c.
3.
Fuel: No. [2] <Insert number> fuel oil.
Minimum Thermal Efficiency: [80] [81] <Insert number> percent.
Ignition: Electronically controlled electric spark with flame sensor.
Safety Controls:
a.
b.
c.
d.
e.
Factory piped and wired to electrical junction box mounted on unit.
Oil-pressure switch.
Control transformer.
Cad-cell safety system.
Manual reset flame safety.
H.
Evaporative Cooling Package: [Single] [Double]-wall cabinet[, fully weatherized for outside
installation], [6-inch- (150-mm-)] [8-inch- (200-mm-)] [12-inch- (300-mm-)] thick
[cellulose] [glass-fiber] media, and with a water-[circulation] [saver] system.
I.
Control Panel: [Surface-mounted] [Recessed, with trim ring,] remote panel.
1.
2.
3.
4.
5.
6.
7.
8.
9.
[On-off] [On-off-auto] fan switch.
[Summer-winter-off] [Heat-vent-cool] switch.[ Automatic changeover.]
Supply-fan operation indicating light.
Heating operation indicating light.
Thermostat.
Damper position potentiometer.
Cooling operation indicating light.
Dirty-filter indicating light operated by unit-mounted differential pressure switch.
Safety-lockout indicating light.
INDIRECT-FIRED H&V UNITS
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Copyright 2001 AIA
MASTERSPEC - OUTLINE
12/01
J.
Refer to Division 15 Section "HVAC Instrumentation and Controls" for control equipment and
sequence of operation.
K.
Control Devices:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
Remote thermostat.
Remote setback thermostat.
Static-pressure transmitter.
Fire-protection thermostats.
Timers: [Seven-day, programming-switch timer] [Solid-state, programmable time
control].
Ionization-type smoke detectors.
Fan Control: Interlocked with exhaust fan(s).
Fan Control: Timer with [fan-discharge thermostat for units with evaporative cooling
package, and] smoke detectors in supply[ and return] air.
Damper Control: [Outdoor-air damper control, 100 percent outdoor-air units]
[Mixed outdoor- and return-air damper control].
Temperature Control: [Factory-mounted sensor in blower outlet] [Wall-mounting,
field-wired sensor] [Timer] [Two or four steps of control using one or two furnace
sections in series] [20 to 100 percent modulation of the firing rate. 10 to 100 percent
with dual furnace units].
Evaporative Cooling Control: [Water-circulation system with sump pump, automatic
fill control, and drain control] [Water-saver system with remote thermostat to
control water-supply valve and timer to activate thermostat].
DDC stand-alone control module for link between unit controls and DDC system.
END OF SECTION 15562
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