SECTION 15790

AIR COILS

PART 1 GENERAL

SECTION INCLUDES

Water coils.

Glycol coils.

Steam coils.

Refrigerant coils.

Electric coils.

RELATED SECTIONS

Section 15260 - Piping Insulation.

Section 15515 - Hydronic Specialties.

Section 15525 - Steam and Steam Condensate Specialties.

Section 15890 - Ductwork: Installation of duct coils.

Section 15952 - Controls and Instrumentation.

Section 16180 - Equipment Wiring Systems.

REFERENCES

ANSI/ARI 410 - Forced-Circulation Air-Cooling and Air-Heating Coils.

ANSI/NFPA 70 - National Electrical Code.

ANSI/UL 1096 - Electric Central Air Heating Equipment.

SMACNA - HVAC Duct Construction Standards, Metal and Flexible.

SUBMITTALS

Submit shop drawings under provisions of Section [01300.] [01340.]

Submit shop drawings indicating coil and frame configurations, dimensions, materials, rows, connections, and rough-in dimensions.

Submit product data under provisions of Section [01300.] [01340.]

Submit product data indicating coil and frame configurations, dimensions, materials, rows, connections, and rough-in dimensions.

Submit manufacturer's installation instructions under provisions of Section [01300.] [01340.]

Submit manufacturer's certificate under provisions of Section [01400] [01405] that [coil capacities, pressure drops, and selection procedures meet or exceed specified requirements.] [coils are tested and rated in accordance with ANSI/ARI 410.]

QUALIFICATIONS

Manufacturer: Company specializing in manufacturing the products specified in this Section with minimum [three [_____] years [documented] experience.

DELIVERY, STORAGE, AND HANDLING

Deliver products to site under provisions of Section [01600.] [01610.]

Store and protect products under provisions of Section [01600.] [01620.]

Protect coil fins from crushing and bending by leaving in shipping cases until installation, and by storing indoors.

Protect coils from entry of dirt and debris with pipe caps or plugs.

PART 2 PRODUCTS

MANUFACTURERS - [HYDRONIC] [STEAM] [REFRIGERANT] COILS

[____________________________] Model [__________.]

[____________________________] Model [__________.]

[____________________________] Model [__________.]

Substitutions: Under provisions of Section [01600.] [01630.]

FABRICATION

Tubes: 5/8 inch (16 mm) OD seamless copper [or brass] arranged in parallel or staggered pattern, expanded into fins, [silver] brazed joints.

Fins: Aluminum [or copper] continuous plate type with full fin collars or individual helical finned tube type wound under tension. [Solder coat copper fin coils.]

Casing: Die formed channel frame of [16] [14] [18] [_____] gage ([1.8] [1.5] [1.2] [_____] mm) galvanized steel with [3/8 inch (9.5 mm)] mounting holes on [3] [6] [_____] inch ([75] [150] [_____] mm) centers. Provide tube supports for coils longer than [36] [40] [48] [_____] inches ([900] [1 000] [1 200] [_____] mm).

Capacity: As scheduled.

WATER HEATING COILS

Headers: Cast iron with tubes expanded into header, seamless copper tube with silver brazed joints, or prime coated steel pipe with brazed joints.

Testing: Air test under water to [200] [350] [_____] psig ([1 380] [2 410] [_____] kPa) for working pressure of [200] [_____] psig ([1 380] [_____] kPa)] and [220] [_____] degrees F ([104] [_____] degrees C).

Configuration: Drainable, with threaded plugs [in headers] for drain and vent; serpentine type with return bends on smaller sizes and return headers on larger sizes.

Fin Spacing: [8] [11] [14] [15] [18] [_____] fins per inch ([3.1] [2.3] [1.8] [1.7] [1.4] [_____] mm on center).

GLYCOL HEATING COILS

Headers: Cast iron with tubes expanded into header, seamless copper tube with silver brazed joints, or prime coated steel pipe with brazed joints.

Testing: Air test under water to [200] [350] [_____] psig ([1 380] [2 410] [_____] kPa) for working pressure of [200] [_____] psig ([1 380] [_____] kPa and [220] [_____] degrees F ([104] [_____] degrees C).

Configuration: Drainable, with threaded plugs [in headers] for drain and vent; threaded plugs in return bends and in headers opposite each tube.

Fin Spacing: [8] [11] [14] [15] [18] [_____] fins per inch ([3.1] [2.3] [1.8] [1.7] [1.4] [_____] mm on center).

STEAM HEATING COILS

Headers: Cast iron with tubes expanded into header, seamless copper tube with silver brazed joints, or prime coated steel pipe with brazed joints.

Testing: Air test under water to [200] [350] [_____] psig ([1 380] [2 410] [_____] kPa) for working pressure of [200] [_____] psig ([1 380] [_____] kPa)] and [220] [_____] degrees F ([104] [_____] degrees C).

Configuration: Drainable, with threaded plugs [in headers] for drain and vent, threaded plugs in return bends and in headers opposite each tube, sloped within frame to condensate connection.

Fin Spacing: [8] [9] [11] [13] [14] [15] [18] [_____] fins per inch ([3.1] [2.8] [2.3] [2.0] [1.8] [1.7] [1.4] [_____] mm on center).

STEAM DISTRIBUTION HEATING COILS

Headers: Cast iron with tubes expanded into header, or prime coated steel pipe with brazed joints.

Tubes: [5/8] [3/8] inch ([16] [9.5] mm) OD steam distributing tubes located within [one] [5/8] inch ([25] [16] mm) OD condensing tubes.

Testing: Air test under water to [200] [350] [_____] psig ([1 380] [2 410] [_____] kPa) for working pressure of [200] [_____] psig ([1 380] [_____] kPa)] and [220] [_____] degrees F ([104] [_____] degrees C).

Configuration: Drainable, with threaded plugs [in headers] for drain and vent; with [steam and return connecting on same end or on opposite end.] [double steam connection, one at each end and either one or two return connections.] [double pass with the single steam connection and return at either end.]

Fin Spacing: [8] [11] [14] [15] [18] [_____] fins per inch ([3.1] [2.3] [1.8] [1.7] [1.4] [_____] mm on center).

WATER COOLING COILS

Headers: Cast iron with tubes expanded into header, seamless copper tube with silver brazed joints, or prime coated steel pipe with brazed joints.

Testing: Air test under water to [200] [350] [_____] psig ([1 380] [2 410] [_____] kPa) for working pressure of [200] [_____] psig ([1 380] [_____] kPa) and [220] [_____] degrees F ([104] [_____] degrees C).

Configuration: Drainable, with threaded plugs [in headers] for drain and vent; threaded plugs in return bends and in headers opposite each tube.

Fin Spacing: [8] [11] [14] [15] [18] [_____] fins per inch ([3.1] [2.3] [1.8] [1.7] [1.4] [_____] mm on center).

REFRIGERANT [COOLING] COILS

Headers: Seamless copper [or brass] tubes with silver brazed joints.

Liquid Distributors: Brass or copper venturi type distributor with seamless copper distributor tubes, 5/16 inch (7.9 mm) OD for refrigerant R-12 and 1/4 inch (6.4 mm) OD for refrigerant R-22; maximum [12] [18] [_____] circuits per

distributor.

Testing: Air test under water at 300 psig (2 070 kPa) for working pressure of [250] [300] psig ([1 720] [2 070] kPa); clean, dehydrate, and seal with dry nitrogen charge.

Configuration: Down feed with bottom suction to prevent trapping of oil.

Fin Spacing: [8] [11] [14] [15] [18] [_____] fins per inch ([3.1] [2.3] [1.8] [1.7] [1.4] [_____] mm on center).

MANUFACTURERS - ELECTRIC COILS

[____________________________] Model [__________.]

[____________________________] Model [__________.]

[____________________________] Model [__________.]

Substitutions: Under provisions of Section [01600.] [01630.]

ELECTRIC COILS

Assembly: ANSI/UL 1096 listed and labelled, with terminal control box and [hinged] cover, splice box, coil, casing, and controls.

Coil: [Enclosed copper tube, aluminum finned element of coiled nickel-chrome resistance wire centered in tubes and embedded in refractory material][.] [or] [Exposed helical coil of nickel-chrome resistance wire with refractory ceramic support bushings.]

Casing: Die formed channel frame of [16] [14] [18] [_____] gage ([1.5] [1.8] [1.2] [_____] mm) galvanized steel with [3/8 inch (9.5 mm)] mounting holes on [3] [6] [_____] inch ([75] [150] [_____] mm) centers. Provide tube supports for coils longer than [36] [40] [48] [_____] inches ([900] [1 000] [1 200] [_____] mm).

Controls: Automatic reset thermal cut-out, built-in [magnetic] [mercury] contactors[,][.] [control circuit transformer and fuse,] [manual reset thermal cut-out,] [air flow proving device,] [fused disconnect,] [unfused disconnect,] [load fuses.]

PART 3 EXECUTION

INSTALLATION

Install in accordance with manufacturer's instructions.

Install in ducts and casings in accordance with SMACNA HVAC Duct Construction Standards, Metal and Flexible.

Support coil sections independent of piping on steel channel or double angle frames and secure to casings. Provide frames for maximum three coil sections. Arrange supports to avoid piercing drain pans. Provide airtight seal between coil and duct or casing.

Protect coils to prevent damage to fins and flanges.	Comb out bent fins.

Install coils level.	[Install cleanable tube coils with 1:50 pitch.]

Make connections to coils with unions and flanges.

On water coils, provide shut-off valve on supply line and lockshield balancing valve on return line. Locate water supply at bottom of supply header and return water connection at top. Provide [manual] [float operated automatic] air vents at high points complete with stopvalve. Ensure water coils are drainable and provide drain connection at low points.

On water [and glycol] heating coils, and chilled water cooling coils, connect water supply to leaving air side of coil (counterflow arrangement).

For cooling coils where air velocity exceeds [500] [550] [_____] ft/min ([2.5] [2.8] [_____] m/sec), provide [three break] [six break] moisture eliminators of 24 gage (0.60 mm) galvanized steel.

Provide drain pan and drain connection for cooling coils. Fabricate drain pan from 20 gage (0.90 mm) galvanized steel. Extend 3 inches (75 mm) from face of coil entering air side, [6] [_____] inches ([150] [_____] mm) from face of coil leaving air side[,][.] [and 4 inches (100 mm) from face of eliminators.] Pipe drain pans individually to floor drain[.] [with water seal trap.]

In steam coils, install vacuum breaker in steam line at or in header. Install steam traps with outlet minimum 12 inches (300 mm) below coil return connection.

On refrigerant coils, provide sight glass in liquid line within 12 inches (300 mm) of coil.

Insulate headers located outside air flow as specified for piping. Refer to Section 15260.

Wire electric duct coils in accordance with ANSI/NFPA 70. Refer to Section 16180.

SCHEDULE

Drawing_Code	HC-1	RHC-1	CC-1

Location

Service

Manufacturer

No. Required

Construction

Type

Width

Height

Face Area

Rows

Circuits

Air

Flow Rate

Velocity

Static Pressure Drop

Heat Transfer Rate

Entering DB Temp

Entering WB Temp

Leaving DB Temp

Leaving WB Temp

Water

Flow Rate

Velocity

Head Loss

Entering Temp

Leaving Temp

Refrigerant

Type

Saturated Suction Temp

Electric

Input (kW)

Remarks

END OF SECTION