23 09 93.11.pdf

Veteran Benefits Administration June 14, 2021

201VB3032 | Hines Finance Center

Specifications – 100% Design

SEQUENCE OF OPERATIONS FOR HVAC DDC

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SECTION 23 09 93.11

SEQUENCE OF OPERATIONS FOR HVAC DDC

PART 1 - GENERAL

1.1 RELATED DOCUMENTS

A. Drawings and general provisions of the Contract, including General and Supplementary

Conditions and Division 01 Specification Sections, apply to this Section.

1.2 SUMMARY

A. Section includes control sequences for DDC for HVAC systems, subsystems, and equipment.

B. Related Requirements:

1. Section 23 09 23 "DDC Systems for HVAC" for control equipment.

1.3 DEFINITIONS

A. Analog Output: Proportional output signal (zero- to 10-V dc, 4 to 20 mA).

B. Binary Output: On/off output signal or contact closure.

C. DDC: Direct digital control.

D. Digital Output: Data output that must be interpreted digitally.

1.4 ACTION SUBMITTALS

A. Product Data:

1. An instrumentation list for each controlled system. Label each element of the controlled system in table format. Show, in the table element name, type of device, manufacturer, model number, and control device product data sheet number.

2. A complete description of the operation of the control system, including sequences of operation. Include and reference a schematic diagram of the controlled system.

B. Shop Drawings:

1. Riser diagrams showing control network layout, communication protocol, and wire types.

2. Schematic diagram of each controlled system. Include all control points labeled with point names shown or listed. Show the location of control elements in the system.

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3. Wiring diagram for each controlled system. Show all control elements labels. Where a control element is the same as that shown on the control system schematic, label with the same name. Label all terminals.

1.5 HEAT PUMP OPERATING SEQUENCE

A. Two-Pipe, Single-Coil, Fan-Coil Unit:

1. Manual Start:

a. Input:

1) Device: Fan switch.

2) Location: Integral to thermostat.

b. Output:

1) Device: Hard wired.

2) Location: Motor controller.

3) Transference: Starter relay.

c. Action: Start and stop fan.

2. Space Temperature:

a. Input:

1) Device: Electronic thermostat.

2) Location: Space.

b. Output:

1) Device: Low-voltage wiring.

2) Location: Control valve.

3) Transference: Valve.

c. Action: Modulate valve to maintain the following space temperature set points:

1) Occupied Cooling Temperature: 72 deg F (24 deg C).

2) Occupied Heating Temperature: 70 deg F (24 deg C).

3) Unoccupied Cooling Temperature: 80 deg F (24 deg C).

4) Unoccupied Heating Temperature: 65 deg F (18 deg C).

3. Occupied Time Schedule:

a. Input:

1) Device: DDC controller.

2) Location: Time schedule.

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3) Transference: DDC controller.

b. Output:

1) Device: Binary output.

2) Location: Motor controller.

3) Transference: Starter relay.

c. Action: Start and stop fan.

4. Space Temperature:

a. Input:

1) Device: Air-temperature sensor.

2) Location: Space.

3) Transference: DDC controller.

b. Output:

1) Device: Analog output.

2) Location: Control valve.

3) Transference: Valve actuator.

c. Action: Modulate valve to maintain the following space temperature set points:

1) Occupied: 72 deg F (24 deg C).

2) Unoccupied: 67 deg F (18 deg C).

d. System Changeover:

e. Input:

1) Device: Liquid temperature sensor or liquid temperature sensor with liquid transmitter.

2) Location: Supply-water piping.

3) Transference: DDC controller.

f. Output:

1) Device: Binary output.

2) Location: Control valve.

3) Transference: Valve actuator.

g. Action: Reverse control-valve action to switch from heating to cooling.

B. Indicate the following on the operator's workstation display terminal:

1. DDC system graphic.

2. DDC system on-off indication (operating or not operating).

3. DDC system occupied/unoccupied mode.

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4. Outdoor-air-temperature indication.

5. Variable-Air-Volume Terminal Air Units with Hydronic Coils:

a. Space/area served.

b. Space occupied/unoccupied.

c. Space temperature indication.

d. Space temperature set point.

e. Space cooling and heating temperature set point, occupied.

f. Space cooling and heating temperature set point, unoccupied.

g. Air-damper position as percentage open.

h. Control-valve position as percentage open.

6. Sequence Control:

a. Space/area served.

b. Space occupied/unoccupied.

c. Space temperature indication.

d. Space temperature set point, occupied.

e. Space temperature set point, unoccupied.

f. Damper position as percentage open.

g. Control-valve positions as percentage open.

PART 2 - PRODUCTS (Not Applicable)

PART 3 - EXECUTION (Not Applicable)

END OF SECTION 23 09 93.11