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7.

15604-3
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

In areas of a building that comply with the Americans with disabilities act,
thermostats shall be mounted at a height of 48" above a finished floor.

Industrial Temperature Controller:

l.

Furnish and install industrial/heavy commercial grade, Temperature Controllers
in NEMA 12, 3R, 4/4X process and production areas capable of controlling
heating and cooling equipment through motor starters, variable speed drives,
industrial relays or other equipment control devices.

The temperature controller shall be programmable for staged on-off heating and
cooling control with front mounted program pushbuttons with LCD backlit
display to show current temperature, setpoint and programming modes.
Temperature controller shall be wall mounted in a metal enclosure. The
enclosure shall meet the NEMA requirements of the area in which they are
installed. Minimum rating shall be dust tight, NEMA 12.

Power shall be 120 VAC with battery backup or programmed parameter stored
in non-volatile memory.

The controller will include a minimum of four (4) form C contacts rated a
minimum of 5 amps at 120 VAC.

Differential shall be programmable from 1-5 °F.

Temperature sensor shall be a shielded and water tight platinum RTD
temperature sensor mounted external to the control enclosure or remotely
mounted as required.

In areas of a building that comply with the Americans with disabilities act,
thermostats shall be mounted at a height of 48" above a finished floor.
Equivalent to:

a. Honeywell Model T775

b. Or equal

Commercial Room Thermostat:

l.

Furnish and install commercial grade thermostats in office and administrative
areas capable of controlling heating, cooling and ventilation. Provide cover
guards in publicly accessible areas.

Low voltage temperature controllers shall be programmable for multistage 7-
day heating and cooling control with front mounted program pushbuttons and
LCD backlit display to show current temperature, setpoint and programming
modes.

Temperature controller shall be wall mounted.

Power shall be 24/120 VAC with real time clock and battery backup or
programmed parameter stored in non-volatile memory.

Temperature sensor shall be a thermistor or RTD sensor internal to the unit.

In areas of a building that comply with the Americans with disabilities act,
thermostats shall be mounted at a height of 48" above a finished floor.

Duct and Immersion Thermostats:

l.

Duct and immersion thermostats of the single input type shall have integral
setpoint adjustments and throttling ranges adequate for the application. Duct
thermostats shall have sensing elements of sufficient length and accuracy to
measure average duct temperature in each location.

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15604-4
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

2. Controllers shall be designed and constructed for equipment room use and shall
not be affected by ambient temperature and humidity.

3. | Duct mounted or immersion type shall have spans of one hundred degrees or
two hundred degrees Fahrenheit as required. Averaging element sensors shall
have a minimum nine-foot capillary element. Temperature sensors shall be of
rigid stem using bimetallic sensing elements except where averaging is
required.

4. — Sensors shall be of corrosion resistant construction, tamper proof, suitable for
mounting on a vibrating surface. If capillary, shall be temperature compensated
and armored or installed in protective tubing.

5. All sensing elements for water pipe mounting shall be furnished complete with
separable protecting wells filled with heat conductive compound. Sensors shall
be factory calibrated and tamper proof. If easily adjustable sensors are
provided, they shall be located inside metal enclosures with cylinder lock and
key to prevent unauthorized setting.

Low Temperature Safety Thermostat:

1. Electric: Low temperature safety thermostats shall have 20 ft. low point
sensitive elements (not averaging type) installed to cover the entire duct
area. These thermostats shall be two position manual reset type. Devices used
on integral coil face and bypass units shall have remote thermostat, and have
bulb in accordance with manufacturer's requirements.

High Temperature Safety Thermostat:

1. Electric: High temperature safety thermostat shall be duct mounted manual
reset type with adjustable setpoint. (75-165 degrees F).

Smoke Detectors:

1. Electric: Smoke detectors shall be of the duct-mounted, photo-electric
type. The units shall be of 120 volts with contacts or additional relays suitable
for the required safety shutdown sequence. The units shall have local alarm
indication, be of the manual reset type have an extra set of normally open and
normally closed contacts for use by the building fire detection system and be
compatible with the building fire detection system.

Thermometers:

1. A thermometer shall be located adjacent to each rigid stem thermostat. A dual
thermometer with liquid-filled remote system shall be mounted adjacent to each
remote bulb thermostat. Averaging bulb thermometers shall be used where
averaging bulb thermostats are required.

2. Provide duct-type thermometers in all fresh air intake, mixed air, return air, and
all supply fan discharges and elsewhere where noted or shown. Thermometers
shall have the proper range scales for the locations where installed.

3. Panel-mounted indicating thermometers shall be minimum two inches’
diameter.

Differential Pressure Controllers:

1. Static pressure regulators shall be direct or reverse acting as required with
adjustable setpoint and throttling range with field calibration capability.

Control Valves: Three-way, two-way, mixing, or diverting service as

required. Operator shall be electric. Valve pressure drop shall not exceed 7 feet water

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Q.

15604-5
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

column (w.c.). Control valves shall be sized by the ATC contractor.

Dampers:

1. All control dampers shall be furnished as part of Section 15862.

2. All dampers shall be installed by sheet metal trades.

Damper Operators and Linkages:

1. Damper operators shall be electric open-close or fully proportioning as
indicated or required.

2. Linkages shall be suitable to connect operator to damper leaves and transmit
full torque of motor. All necessary hardware shall be included with the
linkages.

3. Damper motors shall be quiet in operation and shall have ample power to
overcome friction of damper linkage and air pressure acting on louvers to
position dampers accurately and smoothly. The damper operator mounting
arrangement shall be outside the airstream wherever possible.

4. The operators shall be capable of operating at varying rates of speed to
correspond to the dictates of the controllers and variable load
requirements. The operators shall be capable of operating in sequence when
required by the sequence of the operation. The operators shall have external
adjustable stops to limit the stroke in either direction. The operator linkage
arrangement shall be such as to permit normally open or normally closed
positions of the dampers as required.

5. — Electric Operators:

a. On-off, reversing, or proportional as required.
b. Spring return to closed or open position as required.

6. Dampers associated with emergency generator cooling shall fail open on loss
of electrical power.

Miscellaneous Devices:

1. Provide all the necessary relays, positioners, clocks, transformers, etc. to make
a complete and operable system.

2. Locate these devices on local panel unless specified otherwise.

Miscellaneous Hand Switches and Indicator Lights:

1. Size: 30 mm

2. All indicator lights shall be 120V AC, LED with push to test option.

3. Reference Section 16900 for additional specifications.

4. Number of positions and nameplate legends shall be as indicated in Paragraph
3.1 of this specification.

Relays:

1. Pilot duty relays shall be Form C, UL listed, two (2) to four (4) pole relay with
DIN rail mounted base rated a minimum of 5 amps at 120 VAC. Relay shall
have indicator and mechanical test pushbutton.

2. Industrial relays or contactors shall be used to directly drive 120 VAC single
phase equipment.

3. Refer to Section 16900 for additional requirements.

Panels:

1. Panels shall be provided to enclose all relays, switches, and controllers as
required.

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15604-6
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

Required indicating and control devices shall be installed in the cover.

Terminal strips shall be provided for all electrical connections.

Panels shall be central and/or local as indicated or required.

5. Control Panels shall be provided in accordance to Section 16160.

R. Gauges: Thermometers and pressure indicating gauges shall be provided as shown
on the Drawings and other points throughout the system where the visual indication
of temperature or pressure is required or will prove beneficial to operating personnel
in the operation of the control system. Gauges will not be required on room type
thermostats.

S. Timer/Controller: Repeat Reset Cycle Timers shall be rated 120 volts. The cycle
shall automatically reset to origin upon loss of power. The "ON" timing circuit shall
be continuously adjustable up to a period of 60 minutes. The "OFF" timing circuit
shall be continuously adjustable up to a period of 10 hours. Both circuits shall have
a minimum setting of 3% of range. Setting accuracy shall be 10% of range maximum.
Timer life shall have a warrantee through 10,000,000 operations (no load). An LED
cycle progress annunciator shall be provided with each timing circuit. Contacts shall
be NO and/or NC as detailed on the Drawings, and shall be rated 7 amperes at 125
volts. Repeat, Reset Cycle Timers shall be suitable for recessed panel mounting, and
shall be Automatic Timing Controls 342 series, or equal.

FY

PART 3 - EXECUTION

3.1 DESCRIPTION OF OPERATION
A. Packaged VAV Cooling Air Handling Unit (CRTU-1):

1. | Occupied/unoccupied schedule shall be programmed as provided by the owner.

2. Supply fan:

a. Occupied operation: The fan shall be energized and the integral variable
frequency drive shall modulate the fan speed as necessary to maintain a
0.75” WG static pressure in the supply duct upstream of the VAV terminal
boxes..

b. Unoccupied operation: The fan shall be de-energized.

3. Ventilation:

a. Occupied operation: The outside air damper shall be open to minimum
position and the return air damper open to maximum position to provide
ventilation air.

b. Unoccupied operation: The outside air dampers shall be closed and the
return air damper shall open fully.

c. The exhaust air damper shall be closed at all times unless economizer
operation is available and the outside air damper is open beyond the
required position for ventilation.

4. Cooling: When the temperature rises above 60°F at the outside air temperature
sensor, or when the temperature at the outside air temperature sensor is above
50°F and the outside enthalpy is greater than the indoor enthalpy, CRTU-1 shall
be in cooling mode.

a. Occupied operation: The compressors and hot gas reheat shall
stage/modulate as necessary to maintain a discharge air temperature of
55°F (adj.) at the discharge air temperature sensor.

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5.

15604-7
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

b. Economizer cooling: When the temperature at the outside air temperature
sensor falls below 60°F and the outside air enthalpy is less than the return
air enthalpy during occupied periods; the supply fan shall be in the
occupied mode; and the outside air, exhaust air, and return air dampers
shall modulate from minimum to 100% as necessary to maintain a
discharge air temperature of 60°F (adj.) at the discharge air temperature
sensor.

Safeties:

a. Smoke: If the associated duct smoke detector senses smoke in the air
stream; the RTU fans and compressors shall be de-energized; the return,
exhaust, and outside air dampers shall close; and an alarm and detailed
notification shall be sent to the SCADA system alerting the operator to the
condition.

b. Freeze protection: When the temperature at the discharge air temperature
sensor falls below 45°F (adj.), the outside air and exhaust air dampers shall
close, the return air damper shall open fully, and an alarm and detailed
notification shall be sent to the SCADA system alerting the operator to the
condition. When the temperature at the discharge air temperature sensor
rises above 45°F (adj.), normal operation shall resume.

B. Variable Air Volume Terminal Units (VAV):

1.

Integral digital controls shall operate the unit per the following sequence:

a. Occupied/unoccupied schedule shall be interlocked with CRTU-1.

b. Heating: When the temperature falls below 50°F at the outside air
temperature sensor, the VAV units shall be in heating mode.

i. Occupied operation: The primary air damper shall open to minimum
position.

ii. | Unoccupied operation: The primary air damper shall be closed.

c. Cooling: When the temperature at the outside air temperature sensor rises
above 50°F, VAV units shall be in cooling mode.

i. Occupied operation: The primary air damper shall modulate
between minimum and maximum position as necessary to maintain
the cooling setpoint, 74°F (adj.), at the zone temperature sensor.

ii. | Unoccupied operation: The primary air damper shall be closed. If
the temperature at the zone temperature sensor rises above 85°F
(adj.) The primary air damper shall open to maximum position and
a signal shall be sent to CRTU-1 that unoccupied cooling is required.

C. Packaged Heat Pump Air Handling Unit (CRTU-2&3):

l.
2.

Occupied/unoccupied schedule shall be programmed as provided by the owner.
Supply fan:
a. Occupied operation: the fan shall be energized and operating

continuously.
b. Unoccupied operation: the fan shall be de-energized.
Ventilation:

a. Occupied operation: The outside air damper shall be open to minimum
position and the return air damper open to maximum position to provide
ventilation air.

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15604-8
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

b. Unoccupied operation: The outside air dampers shall be closed and the
return air damper shall open fully.

c. The exhaust air damper shall be closed at all times unless economizer
operation is available and the outside air damper is open beyond the
required position for ventilation.

Cooling: When the outside air temperature rises above 60°F (adj.), or when the

outside air temperature is above 50°F (adj.) and the outside enthalpy is greater

than the indoor enthalpy, the RTU shall be in cooling mode.

a. The compressors shall operate as necessary to maintain the space cooling
setpoint (74°F occupied / 85°F unoccupied adj.).

b. Economizer cooling: When the temperature at the outside air temperature
sensor falls below 60°F and the outside air enthalpy is less than the return
air enthalpy during occupied periods; the supply fan shall be in the
occupied mode; and the outside air, exhaust air, and return air dampers
shall modulate from minimum to 100% as necessary to maintain a
discharge air temperature of 60°F (adj.) at the discharge air temperature
sensor.

Heating: When the outside air temperature falls below 60°F (adj.), the RTU

shall be in heating mode.

a. CRTU-2: The compressors shall operate as necessary to maintain the
heating discharge air temperature (68°F occupied adj.).

b. CRTU-3: The compressors shall operate as necessary to maintain the
space heating setpoint (68°F occupied / 60°F unoccupied adj.).

Gas-Fired Makeup Air Unit (CMUA-1)

1.
2.

Occupied/unoccupied schedule shall be programmed as provided by the owner.

Supply fan:

a. Occupied operation: the fan shall be energized and operating
continuously.

b. Unoccupied operation: the fan shall be de-energized.

Ventilation:

a. Occupied operation: The outside air damper shall be open.

b. Unoccupied operation: The outside air dampers shall be closed.

Heating:

a. The gas-fired furnace shall ignite and stage as necessary to maintain the
discharge air temperature setpoint (55°F adj.)

Ductless Split System Heat Pump (CDS & CHP)

System controls shall be packaged controls provided by the manufacturer.
a. CDS-1A, 1B, & 1C/HP-1

i. Cooling setpoint — 74°F (adj.)

ii. Heating setpoint — 70°F (adj.)
b. CDS-2/ HP-2

i. Cooling setpoint — 85°F (adj.)

ii. Heating setpoint — 55°F (adj.)

Circulating Pump (CCP-1)

The pump shall be energized and operate continuously when either CSF-2A or
CSF-3A is energized and the outside air temperature is less than 50°F (adj.).

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15604-9
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

G. Circulating Pump (GCP-1)
1. |The pump shall be energized and operate continuously when either GSF-1 is
energized and the outside air temperature is less than 50°F (adj.).
H. Heat exchanger (CHX-1 & GHX-1)
1. |The associated steam control valve shall open as necessary to maintain a heating
leaving water temperature in accordance with the following temperature

schedule:
Outside Air Temperature Hot Water Supply Temperature
50°F 140°F
40°F 152°F
30°F 164°F
20°F 176°F
10°F 188°F
O°F 200°F

I. Laboratory Hood Supply Fan (CSF-2A & 3A):
1. | The fan shall be controlled by a local light switch at the associated laboratory
exhaust hood.
2. The three-way heating control valve shall modulate as necessary to maintain
the associated heating coil discharge air temperature setpoint (68°F adj.)
J. Exhaust Fan (CEF-10A & 15A);:
1. | The fan shall be energized and operate continuously.
K. Ventilation Fans (GEF-1, GEF-2, GSF-1):
1. Controlled by the following associated with connected ATC panel:
a. Hand/Off/Auto switch
b. Run cycle timer
c. Light switch interlock
2. When the lights in the space are energized or the switch is in the “Hand”
position the fans shall be in the occupied mode; when the lights in the space are
de-energized the fans shall be in the unoccupied mode.
3. Ventilation:
a. Occupied:
i. The fans shall be energized.
ii. Damper GD-1 shall close.
iii. Damper GD-2 shall open.
iv. Theintegral motorized backdraft dampers on each exhaust fan shall
open.
v. The three-way heating control valve shall modulate as necessary to
maintain the heating coil discharge air temperature setpoint (55°F

adj.).
b. Unoccupied:
i. The fan shall be controlled by the run cycle timer on repeating
schedule:
ii. Active:

(1) The fans shall be energized.
(2) | Damper GD-1 shall close.
(3) | Damper GD-2 shall open.

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15604-10
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

(4) The integral motorized backdraft dampers on each exhaust

fan shall open.
iii. Inactive:

(1) The fans shall be de-energized.

(2) Damper GD-1 shall open.

(3) | Damper GD-2 shall close.

(4) The integral motorized backdraft damper on each exhaust
fan shall close.

(5) The three-way heating control valve shall modulate as
necessary to maintain the heating coil discharge air
temperature setpoint (55°F adj.).

iv. Active —5 minutes; Inactive — 25 minutes (adj.)
4. Heating:

a. When the temperature at the wall mounted thermostat falls below the
setpoint (55°F adj.), GSF-1 shall energize and the heating control valve
shall open to allow full flow through the heating coil.

Intake Dampers (D-SP1 & D-SP2)
1. Dampers shall be interlocked with existing exhaust fan (SEF-2) to be open
when fan is energized.

3.2 INSTALLATION

A.

The automatic temperature control mechanics shall provide supervision and direction
for all trades that are installing equipment supplied by the temperature control
manufacturer.

All controllers, wiring, equipment, etc., shall be installed by mechanics regularly
employed by the temperature control manufacturer.

Control wiring shall be neatly installed, parallel to building lines, and in locations not
subject to damage.

3.3 TESTING AND COMPLETION

A.
B.

Demonstrate the function of each system in the presence of the Engineer.

Upon completion of the project, the control system provider shall:

1. Completely adjust, ready for use, all thermostats, controllers, valves, damper
operators, relays, etc., provided under this Section.

2. Furnish three (3) instruction manuals covering the function and operation of the
control systems on the project for the use of the Owner's operating personnel. A
representative of the ATC systems provider shall be available on site for 8 hours
of start-up and shall conduct an operational test of the system in the presence
and satisfaction of the Engineer's designated representative and the Owner's
representative. During this 8-hour period, the technician shall instruct the
Owner's Representatives in the proper use and routine maintenance of all ATC
equipment.

3.4 OPERATOR TRAINING

A.

Operator Training shall be performed by a duly authorized representative of the ATC
system provider, who is fully trained in the installation, startup and operation of the
equipment.

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3.5

3.6

3.7

15604-11
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

Provide combined training and operational assistance for plant operators in the proper
operations of the ATC system equipment, and in the techniques, methods, schedules,
etc. associated with maintenance.

The level of the training and operational assistance provided shall be as required to
ensure proper understanding of the equipment's operations, maintenance and warranty
conditions. Should the representative require time in addition to the minimums
indicated herein to sufficiently detail the proper operations and maintenance of the
equipment, it will be provided at no additional cost to Owner. Under absolutely no
circumstances shall warrantees become void due to Owner's failure to follow
operational and maintenance procedures which were not fully detailed and described
in Owner's representatives during these sessions.

At the Owner's discretion, the training sessions may be video recorded for Owner's
future use.

The system provider representative shall fill out the Equipment Training Certification
form included within this Section. Training will not be considered complete until this
form has been provided to the Engineer.

IDENTIFICATION

A.

B.

Provide all control equipment, panels and manual controls with black lamacoid
nameplates engraved with white letters indicating the function, tag number, service
or apparatus being served.

Properly number all wires and terminals where applicable.

GUARANTEE

A.

The control system designated on Drawings and plans and herein specified, shall be
guaranteed to be free from original defects in both material and workmanship for a
period of one (1) year of normal use and service, excepting damages from other
causes. This guarantee shall become effective starting the date the Owner begins to
receive beneficial use of the system.

PROGRAMMED MAINTENANCE

A.

Upon completion of the installation, the control contractor shall submit to the Owner
for consideration, an agreement, to provide the necessary programmed maintenance
to keep the various control systems in proper working condition.

This proposed programmed maintenance agreement shall fully describe the
maintenance work to be performed and shall advise the cost of this work during the
1-year guarantee period provided as part of this Contract by the ATC Contractor as
well as for subsequent years thereafter.

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15604-12
AUTOMATIC TEMPERATURE CONTROL (ELECTRIC)

ATC SYSTEM TRAINING CERTIFICATION

Owner: Date:

Project:

Contractor:

ATC System Provider
Representative:

Equipment:

1. I have trained the Owner's personnel in the proper operation and maintenance of the above
equipment.

(Authorized Representative (Date)
of the ATC System Provider)

2. The personnel listed below attended the training session.

(Owner's Representative) (Date)
3. Witnessed by

Wright-Pierce (Date)
Wright-Pierce
Engineers

99 Main Street
Topsham, ME 04086

END OF SECTION

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