consistency in the design and construction of their facilities.
Deviations from these guidelines must be justified through LCC analysis and
submitted to the University for approval.

1.02 References:

A.

Base acoustic performance of terminal units upon units tested according to ARI
880 and ASHRAE Standard 130.

B.

Base occupied space sound level estimates on ARI 885.

C.

Terminal heating coils shall conform to ARI 410.

1.03 Requirements

A.

Base acoustic performance of terminal units upon units tested according to ARI
880 and ASHRAE Standard 130.

B.

Provide unit with factory-mounted 24 volt transformer for single point electrical
connection

C.

Electric actuators shall be sized appropriately with specified control type and
manufactured by Belimo.

PART 2 - PRODUCTS

2.01 Single Duct Variable Air Volume Units:

A.

Units shall be capable of controlling air volume to within plus or minus 5% of air
volume setpoint, as determined by the zone thermostat demand with variations in
inlet pressures from 0.10 to 6 w.g.

B.

Units shall have internal air resistance, including hydronic heating coil, not to
exceed 0.4 w.g. at maximum flow.

C.

Provide external differential pressure taps separate from the control pressure taps
for airflow measurement with a 0-1w.g. range.

D.

Select units at maximum 2,000 FPM and minimum 400 FPM inlet velocity with
unit discharge and radiated sound power levels such that occupied space Noise
Construction Standards, Revised November 2007

5.23.36-1

5.23.36 AIR TERMINAL UNITS
DESIGN AND CONSTRUCTION STANDARD______________________________________
Criteria does not exceed NC-30 per ARI 885.

E.

Units shall be constructed with minimum 22 gauge galvanized steel enclosures.

F.

Casing Leakage: Assembled units shall be so constructed and sealed to limit air
leakage to the following listed quantities at 3" static pressure. If sealing is
required to obtain the leakage performance, seal as for medium pressure ductwork
Hardcast 1602 tape may be used to seal lap joints and flat seams only. Leakage
curves or tables will be required as part of the submittal data. The following is the
maximum allowable casing leakage including all components:






Maximum





Allowed CFM

Maximum Allowable


Diameter

(Area x 2000 fpm)

CFM Casing Leakage

4"-5"-6"
393


8.0
7"-8"

698
14.0
9"-10"
1091
22.0
11"-12" 1571
30.0
13"-14" 2138
40.0

G.

The following is the maximum damper leakage allowable for the various size
diameter inlets. The damper leakage shall not exceed the values listed in the table
below at 6" w.g. differential pressure, following ARI 880 Testing Procedures.






Maximum





Allowed CFM
Maximum Allowable


Diameter

(Area x 2000 fpm)
CFM Damper Leakage

4"-5"-6"

393

6.0
7"-8"


698
10.5
9"-10"
1091
16.5
11"-12" 1571
20.0
13"-14" 2138
30.0

H.

Provide minimum 3/4 internal lining with all edges sealed against airflow erosion
in accordance with NFPA 90A and UL 181.

I.

Unit air volume shall be set at factory and provided such that special tools are not
required for field adjustment.

2.02 Fan Powered Variable Air Volume Units:

A.

Units shall be capable of controlling air volume to within plus or minus 5% of air
volume setpoint, as determined by the zone thermostat demand with variations in
inlet pressures from 0.10 to 6 w.g.

B.

Units shall be constructed with minimum 20 gauge galvanized steel enclosures.
Construction Standards, Revised November 2007

5.23.36-2

5.23.36 AIR TERMINAL UNITS
DESIGN AND CONSTRUCTION STANDARD______________________________________

C.

Damper (air valve) shall have a leakage rate of less than 2% of the boxs
maximum scheduled CFM at two times primary supply air duct static pressure or
3 w.g. (whichever is smaller).

D.

Provide minimum 3/4 internal lining with all edges sealed against airflow erosion
in accordance with NFPA 90A and UL 181.

E.

Fans in parallel terminal units shall be forward curved, centrifugal, direct-drive
motor with SCR controller for airflow adjustments from 60%-100%. The SCR
controller and fan motor shall be harmonically balanced to reduce electrical noise

F.

Fans in series terminal units shall be forward curved, centrifugal with direct-drive
electronic commutated motors (ECM).

G.

Fan and motor assembly shall be internally suspended and isolated from the casing
on rubber in shear isolators. Fan and motor assembly shall be easily accessible
through access panels without disassembling the entire unit. Fan assembly shall
include an anti-backward rotation device.

2.03 Terminal Heating Coils:

A.

Shall be hot water fin and tube type constructed of seamless copper with
aluminum fins mechanically bonded to the tubes and copper headers.

B.

Casing and tube supports shall be minimum 16 gauge galvanized steel.

C.

Coils shall be drainable, suitable for 250 psig working pressure, with circulated
tubes factory tested at not less than 300 psig air pressure.

2.03 Dual Duct Terminal Units (Mixing Laterals):

A.
Dual duct systems, either existing or justified through LCC, shall utilize UT
standard mixing laterals for zone temperature control. Refer to UT Standard
Details (Section 6.01.03) and Section 5.23.31 for mixing lateral construction
details.

B.
Damper casings shall be construct of 18 ga. galvanized sheet metal, sized with
female connections each end.

C.
The damper blades shall be 16 ga. cold rolled, galvanized steel and shall be spot
welded to shaft.

D.
The damper shafts shall be round and operate in rustproof self-lubricating bearings
(not plastic). The end of the shaft at the operator end shall be scored in line with
the damper blade to reference the damper blade position.

E.

Dampers shall be Arrow Model 70-UTA.
Construction Standards, Revised November 2007

5.23.36-3

5.23.36 AIR TERMINAL UNITS
DESIGN AND CONSTRUCTION STANDARD______________________________________

F.
Electric actuators shall be furnished, mounted and adjusted by the BAS contractor.
Terminal volume damper manufacturer shall provide mounting base on terminal
unit for mounting of actuator. Actuator shall be sized for specific application with
a minimum torque of 40 in-lb. and shall utilize brushless motor. Housing shall be
designed for reversing rotation. Actuator shall be proportional control, 0-10V,
spring return with maximum run time of 150 seconds and spring return time of less
than 60 seconds. Maximum power draw of actuator shall be 10VA. All actuators
installed throughout project shall be of the same manufacturer and model.


G.
Electric actuators shall be sized appropriately with specified control type and
manufactured by Belimo.

PART 3
EXECUTION

3.01 Installation:

A.
Maintain NEC and manufacturers recommended clearances for control
enclosures.

B.
Provide manufacturers minimum straight duct inlet requirements.

END OF STANDARD
Construction Standards, Revised November 2007

5.23.36-4