Exhibit E - VRF HVAC SYSTEMS_CITY MULTI_R-32_rev25Dec.pdf

Exhibit “E” - CRFQ ADJ27*14 VRF HVAC Systems City Multi r-32

VARIABLE-REFRIGERANT-FLOW HVAC

SYSTEMS

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SECTION 238129 - VARIABLE-REFRIGERANT-FLOW HVAC SYSTEMS

PART 1 - GENERAL

1.1 SUMMARY

A. Section includes complete VRF HVAC system(s) which may include, but not limited to, the following components:

1. Indoor, exposed, wall-mounted units.

2. Indoor, concealed, ceiling-mounted units for ducting.

3. Indoor, recessed, ceiling-mounted units with 24x24” grilles.

4. Indoor, heat recovery control units (HRCUs).

5. Outdoor, air-source heat recovery units.

6. VRF system controls.

7. VRF system refrigerant and oil.

8. VRF system condensate drain piping.

9. VRF system refrigerant piping.

10. VRF system control cable.

1.2 QUALITY ASSURANCE

A. Manufacturer Qualifications:

1. Nationally recognized manufacturer of VRF HVAC systems and products.

2. Shipped VRF HVAC systems with similar requirements to local market for a continuous period of 10 years within time of bid.

3. VRF HVAC systems and products that have been successfully tested and in use on at least five completed projects.

4. Having complete published online catalog literature, installation, and operation and maintenance manuals for all products intended for use. Resources must be publicly available without login or sign-in as registered account.

5. Having full-time in-house employees for the following:

a. Product research and development.

b. Product and application engineering.

c. Product manufacturing, testing, and quality control.

d. Technical support for system installation training, startup, commissioning, and troubleshooting of installations.

e. Owner training.

B. Installer Qualifications: An entity that employs installers and supervisors who are trained and approved by VRF HVAC system manufacturer.

1. Each employee shall be certified to have successfully completed manufacturer training for proper installation of systems, including, but not limited to, equipment, piping, controls, and accessories indicated and furnished for installation.

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2. Installer certificate shall be valid and current for duration of Project.

3. Retain copies of Installer certificates on-site and make available on request.

4. Each person assigned to Project shall have demonstrated past experience.

a. Demonstrated experience with VRF products being installed for period within five consecutive years before time of bid.

b. Demonstrated experience on five projects of similar VRF system complexity, scope, and value.

C. ISO Compliance: System equipment and components furnished by VRF HVAC system manufacturer shall be manufactured in an ISO 9001 and ISO 14001 facility.

1.3 DELIVERY, STORAGE, AND HANDLING

A. Deliver and store products in a clean and dry place. Protect products from weather, dirt, dust, water, construction debris, and physical damage.

1. Retain factory-applied coverings on equipment to protect finishes during construction and remove just prior to operating unit.

B. Cover unit openings before installation to prevent dirt and dust from entering inside of units. If required to remove coverings during unit installation, reapply coverings over openings after unit installation and remove just prior to operating unit.

C. Comply with manufacturer's written rigging and installation instructions for unloading and moving to final installed location.

1.4 WARRANTY

A. Manufacturer's Warranty: Manufacturer agrees to repair or replace equipment and components that fail(s) in materials or workmanship within specified warranty period.

1. Failures include, but are not limited to, the following:

a. Structural failures.

b. Faulty operation.

c. Deterioration of metals, metal finishes, and other materials beyond normal weathering and use.

2. Warranty Period:

a. For Compressor, 10 year(s) from date of Substantial Completion.

b. For Parts, 10 year(s) from date of Substantial Completion.

B. Installer’s Labor Warranty: Installer agrees to repair or replace equipment and components that fail(s) in materials or workmanship within specified warranty period.

1. Warranty Period 1 year(s) from date of substantial completion.

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PART 2 - PRODUCTS

2.1 VRF HVAC SYSTEMS

A. Manufacturers: Basis of design is CITY MULTI. Subject to compliance with requirements, provide products by one of the following brands only:

1. Mitsubishi Electric & Electronics USA, Inc.

2. Toshiba Carrier Co., Ltd.

3. Johnson Controls, Inc.

2.2 SYSTEM DESCRIPTION

A. VRF HVAC system(s) with variable capacity in response to varying cooling and heating loads. System shall consist of multiple indoor units, outdoor unit module(s), and HRCUs or SVKs when shown on Drawings. Piping, controls, and electrical power to components make operating system(s) complying with requirements indicated.

1. System(s) operation being heat pump or heat recovery as indicated on Drawings.

2. Each system with one refrigerant circuit serving all indoor units connected to system.

B. Electrical Components, Devices, and Accessories: Listed and labeled as defined in NFPA 70, by a qualified testing agency, and marked for intended location and application.

C. AHRI Compliance: System and equipment performance certified according to AHRI 1230-2023.

D. UL Compliance: Comply with UL 60335-2-40.

2.3 INDOOR, EXPOSED, WALL-MOUNTED UNITS

A. Description: Factory-assembled and tested complete unit with components, piping, wiring, and controls required for mating to piping, power, and controls field connections.

B. Cabinet:

1. Material: Painted steel, or coated steel frame covered by a plastic cabinet, with an architectural acceptable finish suitable for tenant occupancy on exposed surfaces.

2. Insulation: Manufacturer's standard internal insulation to provide thermal resistance and prevent condensation.

3. Internal Access: Removable panels of adequate size for field access to internal components for inspection, cleaning, service, and replacement.

Coil Assembly:

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4. Coil Casing: Aluminum, galvanized, or stainless steel.

5. Coil Fins: Aluminum, mechanically bonded to tubes, with arrangement required by performance.

6. Coil Tubes: Copper, of diameter and thickness required by performance.

7. Capacity Control: DX coil by electronic modulating type valve with linear or proportional characteristics. Hydronic coil by modulating control valve.

8. Unit Internal Tubing: Copper tubing with brazed joints.

9. Unit Internal Tubing Insulation: Manufacturer's standard insulation, of thickness to prevent condensation.

10. Factory Charge: Dehydrated air or nitrogen.

11. Testing: Factory pressure tested and verified to be without leaks.

C. Drain Assembly:

1. Pan: Non-ferrous material, with bottom sloped to low point drain connection.

2. Condensate Removal: Gravity.

a. If a floor drain is not available at unit, provide unit with field-installed condensate pump accessory.

3. Field Piping Connection: Non-ferrous material.

D. Fan and Motor Assembly:

1. Fan(s):

a. Direct-drive arrangement.

b. Single or multiple fans connected to a common motor shaft and driven by a single motor.

c. Fabricated from non-ferrous components or ferrous components with corrosion protection finish.

d. Wheels statically and dynamically balanced.

2. Motor: Brushless DC or electronically commutated with permanently lubricated bearings.

3. Motor Protection: Integral protection against thermal, overload, and voltage fluctuations.

4. Speed Settings and Control: Multiple or variable speed with speed setting adjustable via central or wall controllers when present.

5. Vibration Control: Integral isolation to dampen vibration transmission.

E. Filter Assembly:

1. Access: Front, to accommodate filter replacement without the need for tools.

2. Media: Manufacturer's standard washable filter with antimicrobial treatment.

F. Grille Assembly: Manufacturer's standard discharge grille within front face of unit cabinet.

1. Motorized Vane: Adjustable or oscillating flow pattern.

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G. Field-Installed Unit Accessories:

1. Condensate pump for mounting inside wall cavity and capable of at least 10 feet of lift with drain pan level sensor and overflow switch.

2. Condensate pump with integral white plastic housing for exposed surface mounting directly under indoor unit capable of at least 10 feet of lift with drain pan level sensor and overflow switch.

H. Unit Controls:

1. Factory-Installed Sensors:

a. Unit inlet air temperature.

b. Coil entering refrigerant or water temperature.

c. Coil leaving refrigerant or water temperature.

d. Refrigerant detection if coil is DX.

2. Features and Functions:

a. Self-diagnostics.

b. Time delay.

c. Auto-restart.

d. Auto operation mode.

e. Manual operation mode.

f. Filter service notification.

g. Run test switch.

I. Unit Electrical:

1. Field Connection: Single point connection to power entire unit and integral controls.

2. Disconnecting Means: Field-installed circuit breaker or switch, complying with

NFPA 70.

2.4 INDOOR, CONCEALED, CEILING-MOUNTED UNITS FOR DUCTING

A. Description: Factory-assembled and tested complete unit with components, piping, wiring, and controls required for mating to ductwork, piping, power, and controls field connections.

B. Cabinet:

1. Material: Galvanized steel.

2. Insulation: Manufacturer's standard internal insulation to provide thermal resistance and prevent condensation.

3. Duct Connections: Extended collar or flange, or designated exterior cabinet surface, designed for attaching field-installed ductwork.

4. Internal Access: Removable panels or hinged doors of adequate size for field access to internal components for inspection, cleaning, service, and replacement.

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C. Coil Assembly:

1. Coil Casing: Aluminum, galvanized, or stainless steel.

2. Coil Fins: Aluminum, mechanically bonded to tubes, with arrangement required by performance.

3. Coil Tubes: Copper, of diameter and thickness required by performance.

4. Capacity Control: DX coil by electronic modulating type valve with linear or proportional characteristics. Hydronic coil by modulating control valve.

5. Unit Internal Tubing: Copper tubing with brazed joints.

6. Unit Internal Tubing Insulation: Manufacturer's standard insulation, of thickness to prevent condensation.

7. Factory Charge: Dehydrated air or nitrogen.

8. Testing: Factory pressure tested and verified to be without leaks.

D. Drain Assembly:

1. Pan: Non-ferrous material, with bottom sloped to low point drain connection.

2. Condensate Removal: Unit-mounted lifting mechanism, capable of lifting drain water to an elevation above top of cabinet (sizes 54 and smaller only).

3. Field Piping Connection: Non-ferrous material.

E. Fan and Motor Assembly:

1. Fan(s):

a. Direct-drive arrangement.

b. Single or multiple fans connected to a common motor shaft and driven by a single motor.

c. Fabricated from non-ferrous components or ferrous components with corrosion-resistant finish.

d. Wheels statically and dynamically balanced.

2. Motor: PSC, Brushless DC or electronically commutated with permanently lubricated bearings.

3. Motor Protection: Integral protection against thermal, overload, and voltage fluctuations.

4. Speed Settings and Control: Multiple or variable speed with speed setting adjustable via central or wall controllers when present.

5. External Static Settings: Vary based on Low, Medium, or High Static models.

Models as shown on Drawings

a. Low Static settings include 0.02, 0.06, 0.14, or 0.20” WG.

b. Medium Static settings include 0.14, 0.20, 0.28, 0.40, or 0.60” WG.

c. High Static settings include 0.40 or 1.00” WG for 208V and 0.60 or 1.00”

WG for 230V.

6. Vibration Control: Integral isolation to dampen vibration transmission.

F. Filter Assembly:

1. Access: Bottom, side, or rear to accommodate field installation and replacement

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2. Media: Poly Propylene Honeycomb Fabric (Washable) with Low and Medium

Static models. No filter provided with High Static models.

G. Field-Installed Unit Accessories:

1. Side-access filter box with one set MERV 13 Filter.

2. Condensate pump capable of at least 10 feet of lift.

H. Unit Controls:

1. Factory-Installed Sensors:

a. Unit inlet air temperature.

b. Coil entering refrigerant or water temperature.

c. Coil leaving refrigerant or water temperature.

d. Refrigerant detection if coil is DX.

2. Features and Functions:

a. Self-diagnostics.

b. Time delay.

c. Auto-restart.

d. External static pressure control.

e. Auto operation mode.

f. Manual operation mode.

g. Filter service notification.

h. Drain assembly high water level safety shutdown and notification.

i. Run test switch.

I. Unit Electrical:

1. Field Connection: Single point connection to power unit and integral controls.

2. Disconnecting Means: Field-installed circuit breaker or switch.

2.5 INDOOR, RECESSED, CEILING-MOUNTED UNITS WITH 24x24” GRILLES

A. Description: Factory-assembled and tested complete unit with components, piping, wiring, and controls required for mating to ductwork, piping, power, and controls field connections.

B. Cabinet:

1. Material: Painted steel, or coated steel frame covered by a plastic cabinet, with an architectural acceptable finish suitable for tenant occupancy on exposed surfaces.

2. Insulation: Manufacturer's standard internal insulation to provide thermal resistance and prevent condensation.

3. Internal Access: Removable panels of adequate size for field access to internal components for inspection, cleaning, service, and replacement.

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C. Coil Assembly:

1. Coil Casing: Aluminum, galvanized, or stainless steel.

2. Coil Fins: Aluminum, mechanically bonded to tubes, with arrangement required by performance.

3. Coil Tubes: Copper, of diameter and thickness required by performance.

4. Capacity Control: DX coil by electronic modulating type valve with linear or proportional characteristics. Hydronic coil by modulating control valve.

5. Internal Tubing: Copper tubing with brazed joints.

6. Internal Tubing Insulation: Manufacturer's standard insulation, of thickness to prevent condensation.

7. Factory Charge: Dehydrated air or nitrogen.

8. Testing: Factory pressure tested and verified to be without leaks.

D. Drain Assembly:

1. Pan: Non-ferrous material, with bottom sloped to low point drain connection.

2. Condensate Removal: Unit-mounted integral lifting mechanism, capable of lifting drain water to an elevation above top of cabinet.

3. Field Piping Connection: Non-ferrous material.

E. Fan and Motor Assembly:

1. Fan(s):

a. Direct-drive arrangement.

b. Single or multiple fans connected to a common motor shaft and driven by a single motor.

c. Fabricated from non-ferrous components or ferrous components with corrosion protection finish.

d. Wheels statically and dynamically balanced.

2. Motor: Brushless DC or electronically commutated with permanently lubricated bearings.

3. Motor Protection: Integral protection against thermal, overload, and voltage fluctuations.

4. Speed Settings and Control: Multiple or variable speed with speed setting adjustable via central or wall controllers when present.

5. Vibration Control: Integral isolation to dampen vibration transmission.

F. Filter Assembly:

1. Access: Bottom, to accommodate filter replacement without the need for tools.

2. Media: Washable screen.

G. Return/Discharge-Air Grille Assembly: Attached to bottom of unit cabinet.

1. Discharge Pattern: Four-way throw.

a. Discharge Pattern Adjustment: Field-adjustable settings for up and down range of motion for individual vanes. Provide Deluxe controller to enable

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2. Motorized Vanes: Modulating up and down flow pattern for uniform room air distribution.

H. Integral Occupant and Location Detection: Unit includes occupant and location detection for automatic air distribution and energy saving setback control in the following manner-

1. Air Distribution

a. Default distribution operation: Integral occupant and location detection will not be utilized to control air distribution. During COOL mode, vanes move to horizontal airflow direction. During HEAT mode, vanes move to down airflow direction.

b. Direct/Indirect: Vanes automatically move relative to the quadrant(s) where persons are detected.

c. Area: Vanes move to down airflow direction toward areas with a high floor temperature during COOL mode and toward areas with a low floor temperature during HEAT mode. Otherwise, vanes move to the horizontal airflow direction.

2. Energy Saving

a. Default energy operation: Integral occupant and location detection will not be utilized to automatically enable setback or mode changes.

Set point and setback and mode determined by wall controller or central control when provided.

b. “No occupancy energy save”: If there are no persons in the room for 60 minutes or more, energy saving operation (setback) equal to 4°F is performed.

c. “Room occupancy energy save”: If occupancy rate decreases to approximately 30% of the maximum occupancy rate, energy saving operation (setback) equal to 2°F is performed.

d. No occupancy Auto-OFF: If no persons are in the room for set amount of time (60–180 minutes), MODE is automatically changed (OFF, COOL, or HEAT).

I. Outdoor Air Ventilation Connection: Sheet metal knockout for optional connection to outdoor air ventilation duct.

J. Field-Installed Unit Accessories:

1. Accessory grille with integral occupancy and location sensor.

2. Condensate pump capable of at least 10 feet of lift.

K. Unit Controls:

1. Factory-Installed Sensors:

a. Unit inlet air temperature.

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b. Coil entering refrigerant or water temperature.

c. Coil leaving refrigerant or water temperature.

d. Refrigerant detection if coil is DX.

2. Features and Functions:

a. Integral occupancy and location sensor.

b. Time delay.

c. Auto-restart.

d. Auto operation mode.

e. Manual operation mode.

f. Filter service notification.

g. Drain assembly high water level safety shutdown and notification.

h. Run test switch.

L. Unit Electrical:

1. Field Connection: Single point connection to power entire unit and integral controls.

2. Disconnecting Means: Field-installed circuit breaker or switch, complying with

NFPA 70.

2.6 INDOOR, HEAT RECOVERY CONTROL UNITS (HRCUs)

A. Description: Factory-assembled and tested complete unit with components, piping, wiring, and controls required for mating to piping, power, and controls field connections.

1. Specially designed for use in systems with simultaneous heating and cooling.

2. Systems shall include one or multiple units designed by variable refrigerant system manufacturer for field interconnection to make a single refrigeration circuit and multiple indoor units.

3. Units shall respond to calls for HEAT or COOL operation from indoor units by enabling refrigerant or water flow as equipment shown on Drawings require.

a. If flow direction from HRCU alternates, flow in COOL direction to indoor units in HEAT mode during outdoor unit defrost sequence is not allowed.

B. Cabinet:

1. Galvanized-steel construction.

2. Insulation: Manufacturer's standard internal insulation to provide thermal resistance and prevent condensation.

3. Internal Access:

a. Removable panels or hinged doors of adequate size.

b. Access to all internal components for inspection, cleaning, service, or replacement.

C. Drain Pan: If required by manufacturer's design, provide unit with non-ferrous drain pan

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D. Assemblies and Specialties:

1. Specially designed by manufacturer for type of VRF HVAC system being installed, either two or three pipe.

2. Each branch circuit shall have refrigerant and/or water control valve(s) to control flow.

3. Units serving DX indoor units shall include mitigation shut-off valves at each branch circuit.

4. Each branch port connection shall be fitted with an isolation valve to simplify service to any individual branch.

E. Unit Controls:

1. Factory-Installed Sensors:

a. Liquid inlet temperature.

b. Bypass exit area temperature.

c. Bypass outlet temperature.

d. Bypass inlet temperature.

e. High pressure sensor.

f. Medium pressure sensor.

2. Interlock control sequence: digital output for use in interlock sequences; relay adapter kit may be required. Required interlock sequence(s) include-

a. Refrigerant detection by any connected indoor unit.

F. Refrigerant Leak Detection:

1. Sequence upon receiving leak detection signal from any DX indoor unit:

a. Shut-off valves for each port(s) connected DX indoor unit(s) having detected refrigerant close.

b. If indoor unit fan(s) where refrigerant is detected is set to AUTO, fan switches to ON.

c. Refrigerant detection signal output activated.

d. Normal operation continues uninterrupted for ports and DX indoor units where refrigerant is not detected.

G. Unit Electrical:

1. Field Connection: Single point connection to power entire unit and integral controls.

2. Disconnecting Means: Field-installed circuit breaker or switch, complying with

NFPA 70.

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2.7 OUTDOOR, AIR-SOURCE HEAT RECOVERY UNITS

A. Description: Factory-assembled and tested complete unit designed for use in systems with simultaneous heating and cooling.

1. Systems shall consist of one unit, or multiple unit modules that are designed by variable refrigerant system manufacturer for field interconnection to make a single refrigeration circuit, heat recovery control unit(s), and multiple indoor units.

B. Cabinet:

1. Galvanized steel and coated with a corrosion-resistant finish.

a. Coating with documented salt spray test performance of 2000 hours according to ASTM B117 surface scratch test (SST) procedure.

2. Internal Access: Removable panels or hinged doors of adequate size for field access to internal components for inspection, cleaning, service, and replacement.

C. Compressor and Motor Assembly:

1. One or more positive-displacement, direct-drive and hermetically sealed scroll compressor(s) with inverter drive. Non-inverter compressors—where LRA applies—are not allowed.

Cold-Climate Compressor: Hot gas injection to allow increased compression ratio for extended periods without damage or excessive wear.

2. Protection: Integral protection against the following-

a. Refrigerant overcharge and undercharge

b. High and low refrigerant pressure.

c. High refrigerant and oil temperature.

d. Liquid flood back.

e. Thermal and overload.

f. Voltage fluctuations.

g. Phase failure and phase reversal.

h. Short cycling.

3. Speed Control: Configurable to maintain refrigerant evaporating and condensing temperatures while varying refrigerant flow to satisfy cooling and heating loads.

a. Cooling mode fixed 32°F evaporator temperature.

b. Cooling mode fixed 43°F evaporator temperature.

c. Cooling mode variable 32-48°F evaporator temperature.

d. Cooling mode high ambient operation.

e. Heating mode high COP operation.

f. Heating mode high heating output operation.

4. Vibration Control: Integral isolation to dampen vibration transmission.

5. Oil Management: Timed sequence enabled during extended periods of reduced refrigerant flow to ensure proper lubrication over entire operating range.

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Sequences which rely on sensing oil level risk sensor failure or sensor placement not accounting for line length and are not allowed.

6. Crankcase heaters with integral control to maintain safe operating temperature.

7. Fusible plug.

D. Heat-Exchanger Assembly: Individual coil segments for each unit face to simplify future service replacement costs. Documented salt spray test performance of 2000 hours according to ASTM B117 surface test (SST) procedure.

1. Plate Fin Coils:

a. Casing: Aluminum, galvanized, or stainless steel.

b. Fins: Aluminum or copper, mechanically bonded to tubes, with arrangement required by performance.

c. Tubes: Copper, of diameter and thickness required by performance.

2. Zinc-Coated Aluminum Vertical Flat Tube Coils:

a. Series of tubes containing a series of multiple, parallel flow channels layered between refrigerant header manifolds.

b. Construct fins, tubes, and header manifolds of aluminum alloy.

E. Heat-Exchanger Defrost Strategy:

1. Alternate methods based on ambient temperatures.

a. Hot-gas method to maximize efficiency during mild ambient temperatures.

Method prolongs defrost sequence.

1) Segmented coil (single-module systems) or alternating modules (twinned systems) to deliver simultaneous defrost and HEAT delivery indoors.

b. Reverse-cycle method to maximize comfort during extreme ambient temperatures. Method shortens defrost sequence.

1) Leverage below 33.8°F for single-module systems and below 23°F for twinned systems to deliver shorter defrost cycles.

2. Preheat Defrost Operation: Signal to indoor units operating in HEAT to increase space temperature before the start of defrost sequence.

F. Heat-Exchanger Fan and Motor Assembly:

1. Fan(s): Propeller type.

a. Direct-drive arrangement.

b. Fabricated from non-ferrous components.

c. Statically and dynamically balanced.

2. Fan Guards: Removable safety guards complying with OSHA regulations. If using metal materials, coat with corrosion-resistant coating to match performance

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3. Motor(s): Brushless DC or electronically commutated with permanently lubricated bearings and rated for outdoor duty.

4. Motor Protection: Integral protection against thermal, overload, and voltage fluctuations.

G. Field-Installed Unit Accessories:

1. Snow/Hail Protection Kit: Provide heat exchanger coil guards and fan hoods to protect against hail damage

2. Refrigerant Filter/Cleaning System: Replaceable filter core in bypass arrangement from main suction flow to enhance installation quality assurance

3. Open-Design Equipment Support Stand: Adjustable 13-17” height.

H. Unit Controls:

1. Enclosure: Manufacturer's standard, and suitable for unprotected outdoor locations.

2. Factory-Installed Controller: Configurable digital control.

3. Factory-Installed Sensors:

a. Refrigerant suction temperature.

b. Refrigerant discharge temperature.

c. Outdoor air temperature.

d. Refrigerant high pressure.

e. Refrigerant low pressure.

4. Features and Functions: Self-diagnostics, time delay, auto-restart, USB connector to allow running system data up to five days based on storage capacity of memory stick when provided.

I. Unit Electrical:

1. Field Connection: Single point connection to power each unit module or factory-twinned unit and integral controls.

2. Disconnecting Means: Field-installed circuit breaker or switch, complying with

NFPA 70.

2.8 VRF SYSTEM CONTROLS

A. General Requirements:

1. Communicating network may include: Indoor units, outdoor units, HRCUs, SVKs and integral controls connect through a manufacturer-selected network.

2. Network Communication Protocol: Manufacturer proprietary control communication between interconnected units.

3. Integration with Building Automation System: ASHRAE 135, BACnet IP and certified by BACnet Testing Lab (BTL), including the following-

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a. Ethernet connection via RJ-45 connectors and port with transmission at 100 Mbps or higher.

b. Integration shall include control monitoring scheduling change of value notifications.

4. Operator Interface:

a. Operators shall interface with system and unit controls through the following:

1) Operator interfaces integral to controllers

2) Manufacturer-provided central controller.

3) Integration with Building Automation System.

4) Secure-cloud access through web browser software with 1-year prepaid service subscription.

5) N Proprietary software interfaces shall be permitted

b. Users shall be capable of interface with controllers for indoor units’ control to extent privileges are enabled. Control features available to users shall include the following:

1) On/off control.

2) Temperature set-point adjustment.

3) Fan speed control.

c. Interface via secure-cloud access shall allow downloading of system diagnostic information, viewable system diagnostic charts, and email notification of error codes.

B. VRF HVAC System Operator Interface via PC:

1. Central controller(s) connected local-area-network shall be accessible through standard web browser software requiring no manufacturer-specific software be installed on owner-furnished PC.

2. Browser interface shall provide operator with a graphic user interface to allow monitoring and control of multiple central controllers from a single device location through point-and-click mouse exchange.

3. Plan views shall show building plans with location of indoor units and identification superimposed on plans.

4. Controls operation mode of indoor units as individual units, by selected groups of indoor units, or as collection of all indoor units. Operation modes available through central controller shall match those operation modes of controllers for indoor units.

5. Schedules operation of indoor units as individual units, by selected groups of indoor units, or as collection of all indoor units. Schedules daily, weekly, and annual events.

6. Changes operating set points of indoor units as individual units, by selected groups of indoor units, or as collection of all indoor units.

7. Night setback feature to operate indoor units at energy-conserving heating and cooling temperature set-points during unoccupied periods.

8. Supports Multiple Languages: English, French, or Spanish.

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9. Supports Imperial and Metric Temperature Units

10. Displays service notifications and error codes.

11. Monitors and displays cumulative operating time of indoor units.

12. Able to disable and enable operation of individual controllers for indoor units.

13. Information displayed on individual controllers shall also be available for display.

C. Central Controllers:

1. Centralized control for all indoor and outdoor units from a single central controller location.

a. Include multiple interconnected controllers as required.

b. Include backlit, high-resolution color display touch panel.

2. Controls operation mode of indoor units as individual units, by selected groups of indoor units, or as collection of all indoor units. Operation modes available through central controller shall match those operation modes of controllers for indoor units.

3. Schedule operation of indoor units as individual units, by selected groups of indoor units, or as collection of all indoor units.

a. Sets schedule for daily, weekly, and annual events.

b. Schedule options available through central controller shall at least include the schedule options of controllers for indoor units.

4. Changes operating set points of indoor units as individual units, by selected groups of indoor units, or as collection of all indoor units.

5. Optimized start feature to start indoor units before scheduled time to reach temperature set-point at scheduled time based on operating history.

6. Night setback feature to operate indoor units at energy-conserving heating and cooling temperature set-points during unoccupied periods.

7. Able to disable and enable operation of individual controllers for indoor units.

8. Information displayed on individual controllers shall also be available for display through central controller.

9. Multiple RJ-45 ports for direct connection to a local PC and an Ethernet network switch.

10. Start/stop control capability for third-party equipment as required.

11. Accessory surface-mount case.

12. Accessory recess-mount case (for use in 3-1/2” wall cavity).

13. DIN rail mounting kit for installation of central controller in an enclosure.

14. License for Integration with Building Automation System: BACnet over IP communication of indoor unit monitor and control points.

15. Demand response controller kit meeting California Title 24 2022 Building

Energy Efficiency Standards– Demand Responsive Controls compliance (Appendix D of California 2022 Nonresidential and Multifamily Compliance)

16. Niagara Driver for direct BMS connection to central controller(s) for enhanced data set including indoor unit and control points plus outdoor unit monitor points in lieu of BACnet license.

D. Wired Controllers and Sensors for Indoor Units

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1. Simple Controllers for Indoor Units:

a. Single controller capable of controlling multiple indoor units as group.

b. Integral room temperature sensor

c. Temperature Units: Fahrenheit and Celsius.

d. On/Off: Turns indoor unit on or off.

e. Operation Mode: Cool, Heat, Auto, Dehumidification, Fan Only.

f. Temperature Display and Set-Point: Separate set points for Cooling, Heating. Adjustable in 1-degree Fahrenheit increments between.

g. Fan Speed Setting: Select between available options furnished with unit.

h. Airflow Direction Setting: If applicable to indoor unit style, select between available options furnished with the unit.

i. Service Notification Display: "Filter".

j. Error Code Notification Display: Used by service personnel to troubleshoot abnormal operation and equipment failure.

k. Low-voltage power required for controller shall be powered through non-polar connections to indoor unit.

2.9 VRF SYSTEM REFRIGERANT AND OIL

A. Refrigerant:

1. As required by VRF HVAC system manufacturer for system to comply with performance requirements indicated.

2. ASHRAE 34, Class A2L refrigerant classification.

3. R-32

B. Oil:

1. As required by VRF HVAC system manufacturer and to comply with performance requirements indicated.

2.10 VRF SYSTEM CONDENSATE DRAIN PIPING

A. If more than one material is listed, material selection is Contractor's option.

B. Copper Tubing:

1. Drawn-Temper Tubing: According to ASTM B88, Type L (ASTM B88M, Type B)][ASTM B88, Type M (ASTM B88M, Type C) or Type DWV according to

ASTM B306.

2. Wrought-Copper Fittings: ASME B16.22.

3. Wrought-Copper Unions: ASME B16.22.

4. Solder Filler Metals: ASTM B32, lead-free alloys, and water-flushable flux according to ASTM B813.

C. CPVC plastic pipe according to ASTM F441/F441M, Schedule 40, with socket-type pipe fittings according to ASTM F438 and solvent cement according to ASTM F493.

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D. PVC plastic pipe according to ASTM D1785, Schedule 40, with socket-type pipe fittings according to ASTM D2466 and solvent cement according to ASTM D2564, primer according to ASTM F656.

E. Reducers: Where applied to piping connected to unit-mounted integral lifting mechanism, only eccentric reducers oriented horizontally are allowed.

2.11 VRF SYSTEM REFRIGERANT PIPING

A. Refrigerant Piping:

1. Copper Tube: ASTM B280, Type ACR.

2. Wrought-Copper Fittings: ASME B16.22.

3. Brazing Filler Metals: AWS A5.8/A5.8M.

B. Refrigerant Tubing Kits:

1. Factory-rolled and -bundled, soft-copper tubing with tubing termination fittings at each end.

2. Standard one-piece length for connecting to indoor units.

3. Pre-insulated with flexible elastomeric insulation of thickness to comply with governing energy code and sufficient to eliminate condensation.

4. Factory Charge: dehydrated air or nitrogen.

C. Assemblies and Specialties:

1. Divided-Flow Specialty Fittings: Where required by VRF HVAC system manufacturer for proper system operation, VRF HVAC system manufacturer shall furnish specialty fittings with identification and instructions for proper installation by Installer.

2. Refrigerant Isolation Ball Valves: Uni-body full port design with Schrader valve for refrigerant service, rated for maximum system temperature and not less than 800 psi g pressure, and factory tested under pressure to ensure tight shutoff.

2.12 VRF SYSTEM CONTROL CABLE

A. General Requirements: Refer to and verify all wire and cabling requirements with the manufacturer's current installation and operation manuals to ensure compliance with the latest standards and specifications. Cables may not be spliced and shall be continuous from terminal to terminal. Do not splice cable.

B. Low-Voltage Control Network Cabling:

1. Plenum-Rated, Paired Cable: NFPA 70, Type CMP.

a. Shielded wire (2-core) 16 AWG—CVVS, CPEVS or MVVS.

b. PVC insulation and jacket.

c. Foil shielded.

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d. Flame Resistance: Comply with NFPA 262.

e. Maximum cable distance (distance to farthest components) is 1,640 feet.

f. Maximum cable distance from OU to connected IU is 656 feet.

g. Maximum total cable length (sum of all network cabling) is 6,560 feet.

C. Low-Voltage Wall-Mounted Controller Cabling to Indoor Units:

1. Plenum-Rated, Paired Cable: NFPA 70, Type CMP.

a. 22 AWG, 2-conductor unshielded 7-stranded bare copper wire.

1) Residential / multi-family style controllers require 4-conductor.

2) Touch controllers with integral occupancy and light sensing controllers require low-voltage control network cabling to the network.

b. PVC insulation and jacket.

c. Flame Resistance: Comply with NFPA 262.

d. Maximum cable distance (distance from controller to indoor unit) varies by controller style. Refer to manufacturer Submittal or Installation Guides.

D. Transmission power booster provided if additional signal power is required based on connected devices. Coordinate with VRF manufacturer and install near middle of communication bus when required.

PART 3 - EXECUTION

3.1 EXAMINATION

A. Examine substrates, areas, and conditions, with Installer present, for compliance with requirements for installation tolerances and other conditions affecting performance of the Work.

B. Examine products before installation. Reject products that are wet, moisture damaged, or mold damaged.

C. Examine roughing-in for piping and tubing to verify actual locations of connections before equipment installation.

D. Examine roughing-in for ductwork to verify actual locations of connections before equipment installation.

E. Examine roughing-in for wiring and conduit to verify actual locations of connections before equipment installation.

F. Examine walls, floors, roofs, and outdoor pads for suitable conditions where equipment will be installed.

G. Prepare written report, endorsed by Installer, listing conditions detrimental to performance of the Work.

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H. Proceed with installation only after unsatisfactory conditions have been corrected.

3.2 EQUIPMENT INSTALLATION, GENERAL

A. Clearance:

1. Maintain manufacturer's recommended clearances for service and maintenance.

2. Maintain clearances required by governing code.

B. Equipment Restraint Installation: Install equipment with seismic-restraint device.

Comply with requirements for seismic-restraint devices specified in Section 230548 "Vibration and Seismic Controls for HVAC."

3.3 INSTALLATION OF INDOOR UNITS

A. Install units to be level and plumb while providing a neat and finished appearance.

B. Unless otherwise required by VRF HVAC system manufacturer, support ceiling-mounted units from structure above using threaded rods; minimum rod size of 3/8 inch (10 mm).

C. Adjust supports of exposed and recessed units to draw units tight to adjoining surfaces.

D. Protect finished surfaces of ceilings, floors, and walls that come in direct contact with units. Refinish or replaced damaged areas after units are installed.

E. In rooms with ceilings, conceal piping and tubing, controls, and electrical power serving units above ceilings.

F. In rooms without ceiling, arrange piping and tubing, controls, and electrical power serving units to provide a neat and finished appearance.

G. Provide lateral bracing if needed to limit movement of suspended units to not more than 0.25 inch (13 mm).

3.4 INSTALLATION OF OUTDOOR UNITS

A. Install units to be level and plumb while providing a neat and finished appearance.

B. Install outdoor units on support structures indicated on Drawings.

C. Pad-Mounted Installations: Install outdoor units on cast-in-place concrete equipment bases. Comply with requirements for equipment bases and foundations specified in Section 033000 "Cast-in-Place Concrete."

1. Attachment: Install anchor bolts to elevations required for proper attachment to supported equipment.

2. Grouting: Place grout under equipment supports and make bearing surface smooth.

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D. Roof-Mounted Installations: Install outdoor units on equipment supports specified in Section 077200 "Roof Accessories." Anchor units to supports with removable, stainless-steel fasteners.

3.5 GENERAL REQUIREMENTS FOR PIPING INSTALLATION

A. Drawing plans, schematics, and diagrams indicate general location and arrangement of piping and tubing systems. Install piping and tubing as indicated unless deviations to layout are approved on coordination drawings.

B. Install piping and tubing in concealed locations unless otherwise indicated and except in equipment rooms and service areas.

C. Install piping and tubing at right angles or parallel to building walls. Diagonal runs are prohibited unless specifically indicated otherwise.

D. Install piping and tubing above accessible ceilings to allow sufficient space for ceiling panel removal.

E. Install piping and tubing to permit valve servicing.

F. Install piping and tubing at indicated slopes.

G. Install piping and tubing free of sags.

H. Install fittings for changes in direction and branch connections.

I. Install piping and tubing to allow application of insulation.

J. Install groups of pipes and tubing parallel to each other, spaced to permit applying insulation with service access between insulated piping and tubing.

K. Install sleeves for piping and tubing penetrations of walls, ceilings, and floors. Comply with requirements for sleeves specified in Section 230500 "Common Work Results for

HVAC."

L. Install escutcheons for piping and tubing penetrations of walls, ceilings, and floors.

Comply with requirements for escutcheons specified in Section 230500 "Common Work Results for HVAC."

3.6 INSTALLATION OF SYSTEM CONDENSATE DRAIN PIPING

A. General Requirements for Drain Piping and Tubing:

1. Install a union in piping at each threaded unit connection.

2. Install an adjustable stainless steel hose clamp with adjustable gear operator on unit hose connections. Tighten clamp to provide a leak-free installation.

3. If required for unit installation, provide a trap assembly in drain piping to prevent air circulated through unit from passing through drain piping. Comply with more stringent of the following:

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a. Details indicated on Drawings.

b. Manufacturer's requirements.

c. Governing codes.

d. In the absence of requirements, comply with requirements of ASHRAE handbooks.

4. Extend drain piping from units with drain connections to drain receptors as indicated on Drawings. If not indicated on Drawings, terminate drain connection at nearest accessible location that is not exposed to view by occupants.

5. Provide each 90-degree change in direction with a Y- or T-fitting. Install a threaded plug connection in the dormant side of fitting or future use as a service cleanout.

B. Gravity Drains:

1. Slope piping from unit connection toward drain termination at a constant slope of not less than one percent.

C. Pumped Drains:

1. If unit condensate pump or lift mechanism is not included with an integral check valve, install a full-size check valve in each branch pipe near unit connection to prevent backflow into unit.

3.7 INSTALLATION OF REFRIGERANT PIPING

A. Refrigerant Tubing Kits:

1. Unroll and straighten tubing to suit installation. Deviations in straightness of exposed tubing shall be unnoticeable to observer.

2. Support tubing as specified in Section 230516 “Hangers and Supports for HVAC Piping and Equipment.”

3. Prepare tubing ends and make mating connections to provide a pressure tight and leak-free installation.

B. Select system components with minimum 650 psig pressure rating.

C. Install piping as short and direct as possible, with a minimum number of joints and fittings.

D. Arrange piping to allow inspection and service of equipment. Install valves and specialties in accessible locations to allow for service and inspection. Install access doors or panels as specified in Section 083113 "Access Doors and Frames" if valves or equipment requiring maintenance is concealed behind finished surfaces.

E. Install refrigerant piping and tubing in protective conduit where installed below ground.

F. Install refrigerant piping and tubing in rigid or flexible conduit in locations where exposed to mechanical damage.

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G. Unless otherwise required by VRF HVAC system manufacturer, slope refrigerant piping and tubing as follows:

1. Install horizontal hot-gas discharge piping and tubing with a uniform slope downward away from compressor.

2. Install horizontal suction lines with a uniform slope downward to compressor.

3. Traps to entrain oil in vertical runs are not allowed.

4. Inverted traps for twinned systems may be required by manufacturer.

5. Liquid lines may be installed level.

H. When brazing, remove or protect components that could be damaged by heat. Braze pipes with a dry nitrogen purge to avoid oxidation.

I. Before installation, clean piping, tubing, and fittings to cleanliness level required by VRF HVAC system manufacturer.

J. Joint Construction:

1. Brazed Joints

a. Ream ends of tubes and remove burrs.

b. Remove scale, slag, dirt, and debris from inside and outside of tube and fittings before assembly.

c. Construct joints in accordance with AWS's "Brazing Handbook," "Pipe and

Tube" Chapter.

d. Use Type Bag (cadmium-free silver) alloy for joining copper with bronze.

e. The piping being brazed shall be purged of air to remove the oxygen and filled with one of the following inert gases: oxygen-free nitrogen, helium or argon. The piping system shall be purged with an inert gas for a minimum time corresponding to five volume changes through the piping system prior to brazing. The pre-purge rate shall be at a minimum velocity of 100 feet per minute (0.508 m/s). The inert gas shall be directly connected to the tube system being brazed to prevent the entrainment of ambient air. After the pre-purge, the inert gas supply shall be maintained through the piping during the brazing operation at a minimum pressure of 1.0 psi (6.89 kPa) and a maximum pressure of 3.0 psi (20.67 kPa). The joint shall be brazed with a filler metal conforming to AWS A5.8

2. Mechanically Pressed Joints

a. The installing contractor shall be fully trained and qualified by the manufacturer of the mechanically pressed joints to install the selected piping connections.

b. Mechanical joints shall be installed in accordance with the manufacturer’s instructions.

3. Flared Joints

a. Flared fittings shall be installed in accordance with the manufacturer’s instructions. The flared fitting shall be used with the tube material specified by the fitting manufacturer. The flared tube end shall be made by a tool

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4. Soldered Joints

a. Use of soldered joints is prohibited within VRF systems.

3.8 INSTALLATION OF PIPING AND TUBING INSULATION

A. Seal longitudinal seams and end joints with manufacturer's recommended adhesive to eliminate openings in insulation that allow passage of air to surface being insulated.

Installation to maintain a continuous vapor barrier.

B. Insulation Installation on Pipe Fittings and Elbows:

1. Install mitered sections of pipe insulation.

2. Secure insulation materials and seal seams with manufacturer's recommended adhesive to eliminate openings in insulation that allow passage of air to surface being insulated.

C. Insulation Installation on Valves and Pipe Specialties:

1. Install preformed valve covers manufactured of same material as pipe insulation when available.

2. When preformed valve covers are unavailable, install cut sections of pipe and sheet insulation to valve body. Arrange insulation to permit access to packing and to allow valve operation without disturbing insulation.

3. Secure insulation to valves and specialties and seal seams with manufacturer's recommended adhesive to eliminate openings in insulation that allow passage of air to surface being insulated.

D. Where PVC jackets are indicated, install with 1-inch (25-mm) overlap at longitudinal seams and end joints, for horizontal applications. Seal with manufacturer's recommended adhesive.

1. Apply two continuous beads of adhesive to seams and joints, one bead under lap and the finish bead along seam and joint edge.

E. Where metal jackets are indicated, install with 2-inch (50-mm) overlap at longitudinal seams and end joints. Overlap longitudinal seams arranged to shed water. Seal end joints with weatherproof sealant recommended by insulation manufacturer. Secure jacket with stainless steel bands 12 inches (300 mm) o.c. and at end joints.

3.9 INSTALLATION OF DUCT, ACCESSORIES, AND AIR OUTLETS

A. Where installing ductwork adjacent to equipment, allow space for service and maintenance.

B. Comply with requirements for metal ducts specified in Section 233113 "Metal Ducts."

C. Comply with requirements for nonmetal ducts specified in Section 233116 "Nonmetal

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Ducts."

D. Comply with requirements for air duct accessories specified in Section 233300 "Air Duct Accessories."

E. Comply with requirements for flexible ducts specified in Section 233346 "Flexible Ducts."

F. Comply with requirements for air diffusers specified in Section 233713.13 "Air Diffusers."

G. Comply with requirements for registers and grilles specified in Section 233713.23 "Registers and Grilles."

3.10 IDENTIFICATION

A. Identify system equipment, piping, tubing, and valves. Comply with requirements for identification specified in Section 230553 "Identification for HVAC Piping and Equipment."

3.11 FIELD QUALITY CONTROL

A. Manufacturer's Field Service: Engage VRF HVAC system manufacturer's service representative to advise and assist installers; witness testing; and observe and inspect components, assemblies, and equipment installations, including controls and connections.

1. Field service shall be performed by a manufacturer-trained and authorized service representative of VRF HVAC system manufacturer whose primary job responsibilities are to provide direct technical support of its products.

2. Manufacturer-trained and authorized service representative shall provide on-site visits during construction at installation milestones indicated.