HVAC Guide Specifications
Series and Parallel Fan PoweredVAV Terminal Units
Size Range:
90 to 3100 Nominal Cfm (45K)
90 to 3300 Nominal Cfm (45N)
Carrier Model Number (45K Units):
45KA (Analog Electronic Control)
45KC (CCN VAV Electronic Control)
45KD (BACnet VAV)
45KN (No Control or DDC by Others)
45KP (Pneumatic Control)
Carrier Model Number (45N Units):
45NA (Analog Electronic Control)
45NC (CCN VAV Electronic Control)
45ND (BACnet VAV)
45NN (No Control or DDC by Others)
45NP (Pneumatic Control)
45NV (CCN VVT®)
45NB (BACnet VVT)
Part 1 — General
1.01 SYSTEM DESCRIPTION:
Variable air volume control box for installation in aceiling that permits access to the unit. Manufacturershall supply unit(s) of the design, number, size andperformance as shown on equipment drawings andschedules. Unit(s) are for use in conjunction with airdistribution manifolds, distribution ductwork andceiling mounted diffusers.
1.02 QUALITY ASSURANCE:
A. Insulation shall meet NFPA 90A requirements forflame spread and smoke generation and UL 181requirements for anti-erosion, corrosion and fungusproperties.
B. Hot water coils, when specified, shall be tested forleakage at 400 psig with the coil submerged inwater.
C. Electric heating coils, when specified shall be ULor ETL listed and designed to comply withUL Standard 1096, UL 1995 and CSA C22.2No. 236.95.
D. Sound power levels shall be AHRI certified in accordancewith the requirements of AHRI 880, latestedition.
1.03 DELIVERY AND STORAGE:
Units shall be stored and handled per manufacturer'srecommendations.
Part 2 — Products
2.01 Equipment
A. General:
Factory-assembled, externally powered, variable airvolume control terminal. Unit shall be complete witha PSC (permanent split capacitor) motor, damperassembly, flow sensor, externally mounted volumecontroller, collars for duct connection and allrequired features. Control box shall be clearlymarked with an identification label that lists suchinformation as nominal cfm, maximum andminimum factory-set airflow limits, coil type and coilhand, where applicable.
B. Unit Cabinet:
1. Constructed of 20-gage galvanized steel withround inlet collar and rectangular dischargewith flanged duct connection. All primary airinlet collars shall accommodate standard flexduct sizes.
2. Unit shall be insulated with 1/2-in. thick, 11/2-lbequivalent density mat-faced insulation thatmeets the requirements of UL 181 and NFPA90A.
3. Optional 1-in. thick insulation (alternative toItem 2): Unit casing shall be lined with dual density,1-in. thick, 3-lb density fiberglass insulationthat meets UL 181 and NFPA 90A.
4. Optional foil encapsulated insulation (alternativeto Item 2): unit casing shall be lined withnylon reinforced foil-wrapped exposed edges,either 1-in. or 1/2-in. thick, 11/2-lb densityfiberglass insulation that meets UL 181 andNFPA 90A.
5. Optional Steriliner insulation (alternative toItem 2): unit casing shall be lined with 3/16-in.thick, 4-lb density, rigid board insulation withnylon reinforced foil covering insulation fibersthat meets UL 181 and NFPA 90A. Liner shallbe attached to unit casing by insulation adhesiveand full-seam-length Z-strips to enclose and sealthe insulation cut edges.
6. No liner (alternative to Item 2): Unit casing shallbe equipped with no internal insulation liner.
7. Optional Sterilwall insulation (alternative toItem 2): unit casing shall be lined with 1/2-in.thick, 11/2-lb density insulation, meeting UL181 and NFPA 90A, enclosed between the unitcasing and a non-perforated internal sheetmetal cover extending over the fiberglass insulation,as well as covering the liner cut edges.
8. Optional cellular insulation (alternative to Item2): Unit casing shall be lined with 3/8-in. thick,smooth surface, closed-cell elastomeric thermalinsulation for fiber free application.
9. Optional perforated wall insulation (alternativeto Item 2): Unit casing shall be lined with 1/2-in.or 1-in. thick, 11/2-lb dual density fiberglassinsulation. Additional options shall include desityfoil reinforced fiberglass insulation or rigidboard insulation with fiber reinforced foil covering.Insulation shall meet UL 181 and NFPA90A, and shall be enclosed between the unitcasing and a non-perforated internal sheetmetal cover extending over the fiberglass insulation,as well as covering the liner cut edges.
C. Unit Electrical Motors:
Unit electrical motors shall be 120, 208/240, or277-volt, multi-voltage, single-speed, single-phase,permanently lubricated PSC type. Optional277-volt, single-phase ECM (electronically commutatedmotor) fan motors shall be available with eithera VCU (visually controlled unit) (factory/field set,field adjustable) or ACU (analog controlled unit)(remote set and adjusted) fan speed controller (45Ksizes 4, 6, and 7, 45N sizes 4 and 7). Units shall beavailable with fused fan motors.
D. Damper Assembly:
The control air damper assembly shall be constructedof heavy gage galvanized steel with solidshaft rotating in Delrin bearings. Damper shaft shallbe marked on the end to indicate damper position.Damper blade shall incorporate a flexible gasket fortight airflow shutoff and operate over a full 90degrees.
E. Controls:
1. Units shall have pressure-independent pneumatic,electronic, or communicating controls,as specified, capable of maintaining requiredairflow set points ±5% of the unit's capacity atany inlet pressure up to 6 in. wg. The controllersshall be capable of resetting betweenfactory-set or field-set maximum and minimum(>350 fpm inlet duct velocity) set points to satisfythe room thermostat demand.
2. Sensor Type:
a. The unit shall be equipped with an amplifiedlinear averaging flow probe located horizontallyacross the inlet. The sensor will providea differential pressure signal amplified toequal 3 times the velocity pressure with anaccuracy of at least ± 10% throughout therange of 350 to 2600 fpm inlet duct velocity,depending on the controller employed.
b. The unit shall be equipped with a four quadrantlinear cross sensor. This is a multi-pointcenter averaging, inlet flow sensor, availablefor use with pneumatic, analog electric anddigital electric control type units.
F. Special Features:
1. Hot Water Heating Coil:
Hot water coil casing shall be constructed withminimum 20 gage galvanized steel with flangeddischarge for attachment to downstream ductwork.The hot water coil may also be factoryattached to the upstream side of the induced airinlet (45N only). Coils shall be factory-installedon the terminal unit.
a. Fins shall be rippled and corrugated heavygage aluminum, mechanically bonded totubes.
b. Tubes shall be copper with minimum wallthickness of 0.016 in. and with malesolder header connections. Coils shall beleak tested to 400 psig.
c. Number of coil rows and circuits shall beselected to provide performance as requiredby the plans. Coil performance data shall bebased on tests run in accordance with AHRIStandard 410.
2. Electric Heating Coil:
The terminal unit manufacturer shall supplyelectric coils and they shall be UL listed. Constructcoil casing with minimum of 22-gagezinc-coated steel. Elements shall be nickelchrome and supported by ceramic isolators.The integral control panel shall be housed in aNEMA 1 enclosure, with hinged access door foraccess to all controls and safety devices. Electriccoils shall contain a primary automatic resetthermal cutout and differential pressure airflowswitch for proof of airflow. (OPTIONAL) Electriccoils shall include manual reset, fused ornon-fused door interlocking disconnect switch,mercury contactors, thermal cutout, fuse block,dust-tight enclosure construction, all mountedand/or wired within the control enclosure.