Greenheck RV, RVE Maintenance Manual

Document 474612

Model RV / RVE

Dedicated Outdoor Air Unit

Installation, Operation and Maintenance Manual

Please read and save these instructions for future reference. Read carefully before attempting to assemble, install, operate or maintain the product described. Protect yourself and others by observing all safety information. Failure to comply with these instructions will result in voiding of the product warranty and may result in personal injury and/or property damage.

Technical Support

Call: 1-866-478-2574

Email: DOAS@greenheck.com

General Safety Information

Only qualiﬁed personnel should install and maintain this system. Personnel should have a clear understanding of these instructions and should be aware of general safety precautions. Improper installation can result in electric shock, possible injury due to coming in contact with moving parts, as well as other potential hazards. Other considerations may be required if high winds or seismic activity are present. If more information is needed, contact a licensed professional engineer before moving forward.

1. Follow all local electrical and safety codes, as well as the National Electrical Code (NEC), the National Fire Protection Agency (NFPA), where applicable. Follow the Canadian Electrical Code (CEC) in Canada.

2. All moving parts must be free to rotate without striking or rubbing any stationary objects.

3. Unit must be securely and adequately grounded.

4. Do not spin wheel faster than maximum cataloged fan RPM. Adjustments to fan speed signiﬁcantly affect motor load. If the fan RPM is changed, the motor current should be checked to make sure it is not exceeding the motor nameplate amps.

5. Verify that the power source is compatible with the equipment.

6. Never open access doors to the unit while it is running.

WARNING

The roof lining contains high voltage wiring. To prevent electrocution, do not puncture the interior or exterior panels of the roof.

DANGER

• Always disconnect power before working on or near this equipment. Lock and tag the disconnect switch or breaker to prevent accidental power up.

• If this unit is equipped with optional gas accessories, turn off gas supply whenever power is disconnected.

CAUTION

This unit is equipped with a compressed refrigerant system. If a leak in the system should occur, immediately evacuate the area. An EPA Certified Technician must be engaged to make repairs or corrections. Refrigerant leaks may also cause bodily harm.

CAUTION

When servicing the unit, the internal components may be hot enough to cause pain or injury. Allow time for cooling before servicing.

Dedicated Outdoor Air Unit 1

Table of Contents

General Safety Information ......................1

Receiving, Handling, Storage ....................3

Product Overview .............................4

Subassemblies ...............................5

Installation ...................................6

Recommended Electrical and

Gas Supply Entry Locations ....................12

Piping Installation ............................13

Electrical Information. . . . . . . . . . . . . . . . . . . . . . . . . . 14

Control Center Components ....................15

Component Operation. . . . . . . . . . . . . . . . . . . . . . . . . 16

Optional Component Operation .................16

Factory-Installed Refrigeration System ............20

Start-Up – Unit ..............................24

Start-Up Components .........................29

Optional Polymer Energy Wheel .................32

Optional Aluminum Energy Wheel ...............34

Troubleshooting ..............................35

Routine Maintenance .........................41

Reference

Venting Connection Locations ................44

Rated Airflow ..............................46

Our Commitment ...................... Backcover

Dedicated Outdoor Air Unit2

Receiving

This product may have been subject to road salt during transit. If so, immediately wash off all visible white reside from all exterior surfaces. Upon receiving the product, check to ensure all line items are accounted for by referencing the delivery receipt or packing list. Inspect each crate or carton for shipping damage before accepting delivery. Alert the carrier if any damage is detected, do not refuse shipment. The customer shall make notation of damage (or shortage of items) on the delivery receipt and all copies of the bill of lading which should be countersigned by the delivering carrier. If damaged, immediately contact your manufacturer’s representative. Any physical damage to the unit after acceptance is not the responsibility of the manufacturer.

Handling

Units are to be rigged and moved by the lifting brackets provided. Location of brackets varies by model and size. Handle in such a manner as to keep from scratching or chipping the coating. Damaged ﬁnish may reduce ability of unit to resist corrosion.

Unpacking

Verify that all required parts and the correct quantity of each item have been received. If any items are missing, report shortages to your local representative to arrange for obtaining missing parts. Sometimes it is not possible that all items for the unit be shipped together due to availability of transportation and truck space. Conﬁrmation of shipment(s) must be limited to only items on the bill of lading.

Storage

Units are protected against damage during shipment. If the unit cannot be installed and operated immediately, precautions need to be taken to prevent deterioration of the unit during storage. The user assumes responsibility of the unit and accessories while in storage. The manufacturer will not be responsible for damage during storage. These suggestions are provided solely as a convenience to the user.

The ideal environment for the storage of units and accessories is indoors, above grade, in a low humidity atmosphere which is sealed to prevent the entry of blowing dust, rain, or snow. Units designed for outdoor applications may be stored outdoors. All accessories must be stored indoors in a clean, dry atmosphere.

Indoor

Maintain temperatures evenly to prevent condensation. Remove any accumulations of dirt, water, ice, or snow and wipe dry before moving to indoor storage. To avoid condensation, allow cold parts to reach room temperature. Leave coverings loose to permit air circulation and to allow for periodic inspection.

The unit should be stored at least 3½ in. (89 mm) off the ﬂoor. Clearance should be provided to permit air circulation and space for inspection.

Outdoor

The unit should be placed on a level surface to prevent water from leaking into the unit. The unit should be elevated so that it is above water and snow levels. Ensure sufﬁcient support to prevent unit from settling into soft ground. Locate parts far enough apart to permit air circulation, sunlight, and space for periodic inspection. To minimize water accumulation, place all unit parts on blocking supports so that rain water will run off.

Do not cover parts with plastic ﬁlm or tarps as these cause condensation of moisture from the air passing through heating and cooling cycles.

Inspection and Maintenance

While in storage, inspect units once per month. Keep a record of inspection and maintenance performed.

If moisture or dirt accumulations are found on parts, the source should be located and eliminated. At each inspection, rotate the fan wheel by hand ten to ﬁfteen revolutions to distribute lubricant on motor. If paint deterioration begins, consideration should be given to touch-up or repainting. Units with special coatings may require special techniques for touch-up or repair.

Machined parts coated with rust preventive should be restored to good condition promptly if signs of rust occur. Immediately remove the original rust preventive coating with petroleum solvent and clean with lint-free cloths. Polish any remaining rust from surface with crocus cloth or ﬁne emery paper and oil. Do not destroy the continuity of the surfaces. Wipe thoroughly clean with Tectyl® 506 (Ashland Inc.) or the equivalent. For hard to reach internal surfaces or for occasional use, consider using Tectyl® 511M Rust Preventive, WD-40® or the equivalent.

Removing from Storage

As units are removed from storage to be installed in their ﬁnal location, they should be protected and maintained in a similar fashion until the equipment goes into operation.

Prior to installing the unit and system components, inspect the unit assembly to make sure it is in working order.

1. Check all fasteners, set screws on the fan, wheel, bearings, drive, motor base, and accessories for tightness.

2. Rotate the fan wheel(s) by hand and assure no parts are rubbing.

Dedicated Outdoor Air Unit 3

Product Overview

A horizontally conﬁgured High Percentage Outdoor Air unit designed for installation either indoors or outdoors. Each unit has multiple options for cooling and/or heating. The unit is designed to replace air that is exhausted from the building and also heat and cool, as needed. The air volume produced by the unit is constant, but can be optionally modulated to provide a variable air volume (VAV) and recirculation is also offered as an option.

Cooling

Units have the following cooling options available:

• Packaged DX

• Split DX (thermal expansion valve is ﬁeld-provided) Not available on housing sizes 10, 75/150, 110/118.

• Chilled water coil

• Air-source heat pump (ASHP) Not available on housing sizes 10, 75/150, 110/118.

Packaged DX and air-source heat pumps are shipped fully charged with refrigerant and are ready for operation upon arrival.

Heating

There are four different optional heat sources that can be ordered for this unit:

• Indirect gas-ﬁred furnace with one or two sets of heat exchangers

• Electric heat with inﬁnitely variable SCR control

• Hot water coil

• Air-source heat pump (ASHP) Not available on housing sizes 10, 75/150, 110/118.

Models and Capacities

Model Cooling Capacity

RV-10

RV-25

RV-45

RV-75

RV-110

RVE-40

RVE-85

RVE-150

RVE-180

3 to 7 tons

5 to 15 tons

15 to 30 tons

25 to 50 tons

30 to 70 tons

5 to 15 tons

15 to 30 tons

25 to 50 tons

30 to 70 tons

Airﬂow Arrangement

The unit is capable of Constant Air Volume (CAV), Variable Air Volume (VAV), 100% Outdoor Air and have recirculating air options.

Safety Listing

Models are listed per ANSI/UL 1995, Heating and Cooling Equipment and are ETL Certiﬁed.

Dedicated Outdoor Air Unit4

Subassemblies

Blower - Either one, two, or three plenum-type fans. All

units are equipped with a plenum fan for Supply Air and a second may be selected for Exhaust (Relief) Air.

Coils - Evaporator coil (optional)

Condenser coil (optional, packaged DX only) Indoor coil (optional, air-source heat pump only) Outdoor coil (optional, air-source heat pump only) Water coil (optional) Reheat coil (optional)

Compressors - Each unit having packaged DX will

have either one, two or four refrigerant compressors. Optionally, one of the compressors may be a digital or inverter scroll type compressor. Air-source heat pump units will have one inverter scroll compressor and may contain a second staged compressor.

Dampers - Motorized intake air damper, optional

motorized recirculating damper. Optional return air damper. Optional gravity-type exhaust damper.

Optional Barometric Relief Damper - Used during

economizer mode of the unit when building pressure increases, relief damper will open due to over pressurization.

Electric Heater - An SCR controlled electric heater (not

shown) is available on the units. It has its own control panel and may require a separate power supply. See unit-speciﬁc wiring diagram.

Supply Filters - Housing size 110/180 is available with

a ﬁlter bank depth of either 2,4 or 6-inch. All other housings are available with a ﬁlter bank depth of either 2 or 4-inch.

Low Sound Condenser Fans

(optional)

Indirect Gas-Fired Furnace - Housing sizes 10, 25/40

and 45/85, use furnace model PVG. Housing sizes 75/150 use furnace models PVG 600-800 or HMA 1000-

1200. Housing sizes 110/180 use furnace model HMA 600-1200.

Packaged DX System - Any unit may be ordered with

a packaged DX system. Housing size 10 will use one compressor; housing size 25/40 will include either one or two compressors; housing size 45/85 will include two compressors; housing size 75/150 will include three compressors; housing size 110/180 will include four compressors; a condenser coil(s) and evaporator coil(s) and all required components. Units that have packaged DX are charged with R410A refrigerant. Do not use tools or parts designed for other refrigerants on these units.

Air-Source Heat Pump - Units having an air-source heat

pump will include either one or two compressors, an indoor and outdoor coil, and all required components. Air-source heat pump units are charged with R410A refrigerant. Do not use tools or parts designed for other refrigerants on these units. Not available on housing sizes 10, 75/150, 110/118.

Split DX - The unit may be ordered with a split DX

system for connection to a building cooling system. Thermal expansion valve (TXV) is ﬁeld-provided. Not available on housing sizes 10, 75/150, 110/118.

Vestibule - Some units may be ordered with a factory-

assembled vestibule that is to be ﬁeld-attached to the side of the unit. See lifting instructions.

Energy Wheel (RVE)

(optional)

Outdoor Air Filters

(pre-wheel)

Condenser Coils

(optional)

Packaged DX Compressors

(optional)

Furnace Vest Plate

and

Furnace Control Center

(optional)

Main Control

Center

Plenum-Type

Supply Air Blower

Indirect Gas-Fired Furnace

(optional)

Weatherhood Filters

(metal mesh)

Outdoor Air

Damper

Plenum-Type

Exhaust Air Blower

Recirculating

Damper

Coils

(optional)

Dedicated Outdoor Air Unit 5

Installation

Typical Unit Weights and Dimensions

Housing size 10

Housing size 25/40 and 45/85

Housing size 75/150

Component Access

1 Optional Inverter Compressor

2 Optional Compressor/Electrical

3 Optional Gas Furnace/Optional Electric Heater

4 Electrical

5 Supply Blower

6 Coil

7 Filters

8* Exhaust Blower/Optional Electric Preheat

9 Powered Exhaust Blower Section

* When a powered exhaust fan (or RVE) is selected, door 8 will

be to the immediate right of door 7.

Dedicated Outdoor Air Unit6

Housing size 110/180

Installation

Typical Unit Weights and Dimensions

Nominal

Model

tonnage

(tons)

RV-10 3-7 58.1 44.0 82.2

RV-25 5-15 59.3 52.5 98.6

Height

(H)

Width

(W)

Length

Intake

(L)

/149.5822.1 30.1 2,700

22.3 NA 1,180

RV-45 15-30 72.5 68.2 1097/163.2827.7 30.1 4,500

RV-75 25-50 101.3 98 155.2 39/47.5

RV-110 30-70 99.5 96 185 45.3 NA 7,950

RVE-40 5-15 59.3 52.5 149.5/180.5

22.1 30.1 3,400

RVE-85 15-30 72.5 68.2 163.2/197.2527.1 30.1 5,100

RVE-150 25-50 101.3 98 200.4 47.5 NA 8,000 Bottom End

RVE-180 30-70 99.5 96 263

/307

45.3 NA 10,450

(A)

Condensing

Section

(B)

NA 6,500

Nominal

weight (lbs)

Outdoor

Intake

End

Supply

Discharge

Bottom

Side

Bottom

Side

Return

Intake

Bottom or

End

Bottom,

End

Side

Bottom or

End

Bottom or

Side

Bottom,

End

Side

Bottom or

Side

Exhaust

Discharge

End

Side

End

Side

End

Side

All dimensions are shown in inches. Weight is shown in pounds and includes largest supply and exhaust fans, PDX with reheat, largest indirect-gas ﬁred furnace, and all dampers. Actual weights will vary based on the unit conﬁguration.

Only available with powered exhaust

Only available without barometric relief

Only available with barometric relief

Above 12,000 cfm

Length with side return

Length with bottom return

Length with bottom or end return

Length with powered exhaust

Length with powered exhaust bumpout

Optional indirect gas-fired furnace bumpout length is additional 13.3 inches

Dedicated Outdoor Air Unit 7

Installation

Service Clearances

ACCESS DOOR

ACS SIDE

CONTROL

CENTER

CONDENSING SECTION

COMPRESSORS

SUPPLY FAN

HGRH COIL

NA from CS

COOLING COIL

SUPPLY FILTERS

EXHAUST AIR FILTERS

EXHAUST AIR

WEATHERHOOD

WHEEL CASSETTE

EXHAUST FAN

OUTDOOR AIR FILTERS

NA from Unit

OUTDOOR AIR

WEATHERHOOD

OAI

Model

ACS

Access

Side

ACCESS DOOR

Control Cabinet End

Indoor

Other

Mounted

with IG

ACCESS DOOR

OAI

Outdoor Air Intake

Outdoor

Mounted

Indoor

Mounted

CASSETTE REMOVAL

*NA

from Unit

ACCESS DOOR

Condensing

ACCESS DOOR

from

Section

from Piping

Vestibule

(not shown)

Furnace

RV-10 50 42 NA 36 NA 24 NA NA

RV-25 40 42 72 42 18 24 18 30

RV-45 36 58 72 42 18 24 18 30

RV-75 48 48 NA 87 NA 48 NA NA

RV-110 48 48 NA 60 NA 48 NA NA

RVE-40 40 42 72 42 18 24 18 30

RVE-85 36 58 72 42 18 24 18 30

RVE-150 48 48 NA 87 NA 48 NA NA

RVE-180 48 48 NA 60 NA 48 NA NA

All dimensions are shown in inches.

*No condensing section or piping vestibule, or unit has top condensing section.

Dedicated Outdoor Air Unit8

Installation

Additional Clearances for Packaged DX Units

Packaged DX units require additional clearance because they must have unrestricted air movement around the condenser coil and condenser fans. Hot air is being discharged from the condenser fans during operation. Enough clearance must be provided to avoid recirculation or coil starvation. When equipped with condenser coils, the unit should never be placed under an overhang or inside a building. A minimum of 48inches above the condenser fans is acceptable, but unobstructed is strongly recommended.

Minimum 48 inches clearance

Condenser Fans

Minimum 18 inches

clearance

Condenser Coil

End view of rooftop unit with Packaged DX

Handling Concerns for Packaged DX or Air-Source Heat Pump

Units with PDX or ASHP have a system that is pressurized with refrigerant. If damage occurs, the refrigerant could leak into the atmosphere or cause bodily harm due to the extreme cold nature of expanding refrigerant. Use protective equipment such as gloves and safety glasses to minimize or prevent injury in case of a system leak during installation.

Before Lifting

Before lifting, be sure that all shipping materials have been removed from the unit.

Vestibule

Determine whether or not the unit has a vestibule that must be ﬁeld-attached to the side of the unit. Vestibules are shipped assembled but detached from the unit. They have lifting lugs on them so they can also be lifted by crane, but the installed location of the unit may make it preferable to install the vestibule on the unit prior to lifting.

Field Power Access

Determine where high voltage and low voltage wiring is to be brought into the cabinet. If wiring is to be brought into the cabinet through the ﬂoor, see Alternate Supply Entry Locations in this manual. If unit is to be installed on a roof, cut access openings in the roof deck as needed.

Additional Clearances for Air Source Heat Pump

IMPORTANT

Air-source heat pumps are equipped with a defrost cycle to remove ice from the outdoor coil. During defrost cycles, melted water may drip from the bottom of the refrigeration section under the outdoor coil. In cold climates, proper drainage/heat tape must be installed under the outdoor coil to prevent the buildup of ice on the roof.

Air-source heat pump units require additional clearance because they must have unrestricted air movement around the outdoor coil and outdoor fans. Enough clearance must be provided to avoid recirculation or coil starvation. Air-source heat pump units should never be placed under an overhang or inside a building. A minimum of 48-inches above the outdoor fans is acceptable, but unobstructed is strongly recommended.

Dedicated Outdoor Air Unit 9

Installation

Lifting

1. Ensure that all shipping materials have been

removed from unit.

2. To assist in determining rigging requirements,

weights are provided in the Unit Weights & Dimensions section of this manual.

3. Unit must be lifted by all lifting lugs provided at top

of unit.

4. Spreader bars must span the unit to prevent

damage to the cabinet by the lift cables.

5. Never rest the spreader bar on the unit.

WARNING

Spreader bars are required to prevent damage to the cabinet, failure to do so can result in damage that is the installer’s responsibility.

6. Always test-lift the unit to check for proper balance

and rigging before hoisting to desired location.

7. Never lift unit by weatherhood.

8. Never lift units in windy conditions.

9. Preparation of curb and roof openings should be

completed prior to lifting unit to the roof.

10. Check to be sure that gasketing (supplied by

others) has been applied to the top of the curb prior to lifting the unit and setting on the curb.

11. Do not use forklifts for handling unit on housing

sizes 25/40, 45/85, 75/150, or 110/180.

12. If using forklift on housing 10, use forks with 48-

inch length and ensure forks extend to opposite side of unit using factory-installed forklift pockets at unit base.

Roof Curb Mounting

Roof curb details, including duct locations and dimensions, are to be found in the roof curb assembly instructions.

Rooftop units require curbs to be mounted ﬁrst. The duct connections must be located so they will be clear of structural members of the building.

1. Factory-supplied roof curbs. Roof curbs are model GKD which are shipped in a knockdown kit (includes duct adapters) and require ﬁeld assembly (by others) on all units except RV-110 and RVE-180, which are shipped assembled. Assembly instructions are included with the curb kit.

2. Install curb. Locate curb over roof opening and fasten in place. Check that the diagonal dimensions are within ± 1/8inch of each other and adjust as necessary. For proper coil drainage and unit operation, it is important that the installation be level. Shim the curb as required to level. Install gasketing on top surface of curb (provided by others).

3. Install ductwork. Installation of all ducts should be done in accordance with SMACNA and AMCA guidelines. Duct adapters are provided to support ducts prior to setting the unit.

4. Set the unit. Lift unit to a point directly above the curb and duct openings. Guide unit while lowering to align with duct openings. Roof curbs ﬁt inside the unit base. Make sure the unit is properly seated on the curb and level.

5. Fasten the unit, Fasten the unit to the curb/ equipment support(s) using appropriate methods. The installer is responsible for determining appropriate support and fastening methods to ensure compliance with all applicable codes.

6. Install vestibule. If unit was ordered with a vestibule and it has not yet been attached to the unit, caulk and attach the vestibule at this time.

Dedicated Outdoor Air Unit10

Typical Unit with Condensing Section and

Factory-Supplied Curb Kit

Installation

Optional Piping Vestibule

If the unit was ordered with the vestibule, the NA (NonAccess side) clearance dimension must be measured from the vestibule.

Typical Unit with Piping Vestibule and

Factory-Supplied Curb Kit

Rail Mounting and Layout

• The units may be installed on rails provided and installed by others. Ensure that rails are designed to handle the weight of the unit and provide proper load distribution on building supports.

• Make sure that rail positioning does not interfere with the openings on the unit.

• Rails should run the width of the unit and extend beyond the unit a minimum of 12 inches on each side.

• Set unit on rails.

Ductwork Conﬁgurations

NOTE

Downblast Discharge Ductwork - whenever

downblast discharge is used, the ductwork directly beneath the unit must be connected with either a “T” or an “L” configuration and the area directly beneath the heat source must not have any openings such as louvers or grates.

Typical Unit Installed on Rails Supplied by Others

No louvers or grates

Dedicated Outdoor Air Unit 11

Recommended Electrical and Gas Supply Entry Locations

Manufacturer recommends that electrical service and gas supply be brought into the cabinet through the end wall, as shown below. There are three penetrations into the cabinet that are required; one for high voltage supply wiring, one for low voltage control wiring and one for either gas supply or high voltage supply wiring for an electric heater.

Optional Unit Disconnect

Indirect Gas Supply Location

Field Wiring

Recommended Gas and Electric Supply Entry Locations

Alternate Supply Entry Locations

Each installation is unique and as a result, alternate entry locations may be ﬁeld-located. Before using any alternate entry location, verify the suitability of the location and ensure the use of an alternate location does not interfere with unit wiring, components or functionality.

Optional Gas Piping

Units with indirect gas-ﬁred furnaces require ﬁeldsupplied and installed gas supply piping.

Housing

Size

25/40

45/85

75/150

110/180

Total Heating

Capacity

(Input in MBH)

100

150

200

100

150

200

250

300

500

600

800

100

1200

600 1” NPT

800

1200

Gas

Connection

Size

Max Gas Pressure

¾” NPT 14 in. wg.

¾” NPT 14 in. wg.400

¾” NPT

14 in. wg.

1” NPT

2” NPT1000

13.5 in. wg.

Gas Connections

If this unit is equipped with an indirect gas-ﬁred furnace, connection to an appropriate gas supply line will be required. For complete information on installation procedures for the optional gas furnace, refer the PVF/PVG Indirect Gas-Fired Heat Module Installation, Operation, and Maintenance Manual.

Ground

Gas Cock

From Gas Supply

Bleeder Valve or 1/8 in Plugged Tap

Typical Gas Supply Piping Connection

Joint

Union

8 in. Trap

Gas to

Controls

WARNING

Never drill holes in the roof of the unit! There is high voltage wiring located between the inner and outer roof panels. Damage to the wiring could cause severe bodily harm or death.

NOTE

110/180 gas furnaces are designed for gas pressure of 5-13.5 in. wg for natural gas (6-inch minimum on single 500 and 600 MBH furnaces) and 11-13.5 in. wg for LP. If the gas pressure at the job location is greater than 13.5 in. wg, an additional regulator is required to reduce pressure. For other RV and RVE models, reference the Model PVF and PVG IOM.

Dedicated Outdoor Air Unit12

Piping Installation

Optional Coil Piping

Factory-installed cooling and heating components are mounted in the coil section of the unit. The coil section is downstream of the energy wheel on the supply air side of the unit. Note the coil connection locations on the picture. Coil connections are located external to the unit.

Note: DX coil liquid connection is internal to units.

Water Coils

1. Piping should be in accordance with accepted industry standards. Pipework should be supported independently of the coils. When installing couplings, do not apply undue stress to the connection extending through the unit. Use a backup pipe wrench to avoid breaking the weld between coil connection and header.

2. Connect the water supply to the bottom connection on the air leaving side and the water return to the top connection on the air entering side. Connecting the supply and/or return in any other manner will result in very poor performance. Be sure to replace factory-installed grommets around coil connections if removed for piping. Failure to replace grommets will result in water leakage into the unit and altered performance.

3. Water coils are not normally recommended for use with entering air temperatures below 40°F. No control system can be depended on to be 100% safe against freeze-up with water coils. Glycol solutions or brines are the only safe media for operation of water coils with low entering air conditions. If glycol or brine solutions are not used, coils must be drained when freezing conditions are expected. If required,

vent and drain connections must be fieldpiped, external to the unit.

4. Pipe sizes for the system must be selected on the basis of the head (pressure) available from the circulation pump. The velocity should not exceed 6 feet per second and the friction loss should be approximately 3 feet of water column per 100 feet of pipe.

5. For chilled water coils, the condensate drain pipe should be sized adequately to ensure the condensate drains properly. Refer to Drain Trap section.

Direct Expansion (DX) Coils (Split DX)

1. Piping should be in accordance with accepted industry standards. Pipework should be supported independently of the coils. Undue stress should not be applied at the connection to coil headers.

2. The condensate drain pipe should be sized adequately to ensure the condensate drains properly. Refer to Condensate Drain Trap section.

3. When connecting suction and liquid connections make sure the coil is free from all foreign material. Make sure all joints are tight and free of leakage. Be sure to replace factory-installed grommets around coil connections if removed for piping.

4. Manufacturer does not supply compressor, condensing units, or thermal expansion valve (TXV) with standard models. For further instruction on DX coil installation and operation contact your compressor and/or condenser manufacturer.

Condensate Drain Trap

This unit is equipped with a stainless steel condensate pan with a stainless steel connection. It is important that the drain connection be ﬁtted with a P trap to ensure proper drainage of condensate while maintaining internal static pressures and to prevent migration of sewer gas back into the unit.

A P trap assembly (kit) is supplied with each unit and is to be assembled and installed as local conditions require and according to the assembly instructions provided with the P trap. If local and area codes permit, the condensate may be drained back onto the roof, but a drip pad should be provided beneath the outlet. If local and area codes require a permanent drain line, it should be fabricated and installed in accordance with Best Practices and all codes.

In some climates, it will be necessary to provide freeze protection for the P trap and drain line. The P trap should be kept ﬁlled with water or glycol solution at all times and it should be protected from freezing to protect the P trap from damage. If severe weather conditions occur, it may be necessary to fabricate a Ptrap and drain line of metal and install a heat tape to prevent freezing.

Condensate Overﬂow Switch

This unit is equipped with an optional factory-mounted condensate overﬂow switch. In the event that a high level of condensate is detected, the microprocessor controller will trigger an alarm and shutdown the unit.

Dedicated Outdoor Air Unit 13

Electrical Information

WARNING

The roof lining contains high voltage wiring. To prevent electrocution, do not puncture the interior or exterior panels of the roof.

WARNING

To prevent injury or death due to electrocution or contact with moving parts, lock disconnect switch open. For units with a gas furnace, if you turn off the power supply, turn off the gas.

IMPORTANT

Before connecting power to the unit, read and understand the following instructions and wiring diagrams. Complete wiring diagrams are attached on the inside of the control center door(s).

IMPORTANT

All wiring should be done in accordance with the latest edition of the National Electric Code ANSI/NFPA70 and any local codes that may apply. In Canada, wiring should be done in accordance with the Canadian Electrical Code.

IMPORTANT

The equipment must be properly grounded and bonded. Any wiring running through the unit in the airstream must be protected by metal conduit, metal clad cable or raceways.

CAUTION

If replacement wire is required, it must have a temperature rating of at least 105ºC, except for an energy cut-off or sensor lead wire which must be rated to 150ºC.

DANGER

High voltage electrical input is needed for this equipment. This work should be performed by a qualified electrician.

CAUTION

Any wiring deviations may result in personal injury or property damage. Manufacturer is not responsible for any damage to, or failure of the unit caused by incorrect final wiring.

Determine the Size of the Main Power Lines

The unit’s nameplate states the voltage and the unit’s MCA. The main power lines to the unit should be sized accordingly. The nameplate is located on the outside of the unit on the control panel side.

Determine the Size of Electric Heater Wiring

An optional electric heater may require a separate power supply. The power connection should be made to the factory-provided electric heater disconnect and must be compatible with the ratings on the nameplate, supply power voltage, phase and amperage. Consult ANSI/NFPA 70 and CSA C22.1 for proper conductor sizing.

Provide the Opening(s) for the Electrical Connections

Electrical openings vary by unit size and arrangement and are ﬁeld-supplied.

Connect the Power Supplies

Connect the main power lines and electric heater power lines to the disconnect switches or terminal blocks and main grounding lug(s). Torque ﬁeld connections to manufacturer’s recommendations.

Wire the Optional Convenience Outlet

The convenience outlet requires a separate 115V power supply circuit. The circuit must include short circuit protection which may need to be supplied by others.

Connect Field-Wired Low Voltage Components

Most factory-supplied electrical components are prewired. To determine what electrical accessories require additional ﬁeld-wiring, refer to the unit-speciﬁc wiring diagram located on the inside of the control center access door.

The low voltage control circuit is 24 VAC and control wiring should not exceed 0.75 ohms.

Control wires should not be run inside the same conduit as that carrying the supply power. Make sure that ﬁeld-supplied conduit does not interfere with access panel operation. All low voltage wiring should be run in conduit wherever it may be exposed to the weather.

If wire resistance exceeds 0.75 ohms, an industrialstyle, plug-in relay should be added to the unit control center and wired in place of the remote switch (typically between terminal blocks R and G on the terminal strip. The relay must be rated for at least 5 amps and have a 24 VAC coil. Failure to comply with these guidelines may cause motor starters to “chatter” or not pull in which can cause contactor failures and/or motor failures.

Field-Provided Disconnect

If ﬁeld-installing an additional disconnect switch, it is recommended that there is at least four feet of service room between the switch and system access panels. When providing or replacing fuses in a fusible disconnect, use dual element time delay fuses and size according to the rating plate.

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Control Center Components

Main Control Center Components

Image represents a typical installation for RVE-40 or RVE-85. Components and locations will vary on other models.

Electrical Cabinet

1. Power distribution block; high voltage supply is terminated here

2. Fuse holders

3. Phase monitor

4. Unit Disconnect

5. Condensing fan motor contactors

6. Wheel motor contactor

7. Compressor motor contactors

Controls Cabinet

8. Transformer

9. VFDs

10. Microprocessor controller

11. Monitoring points

12. Low voltage terminal strip

13. Relays

14. Dirty ﬁlter switches

15. Wheel pressure switch

16. Outdoor airﬂow monitor

17. Exhaust airﬂow monitor

18. Digital scroll controller

Controls Cabinet

Accessible via compressor door

Electrical Cabinet

Accessible via control center door

2 2

Optional Indirect Gas-Fired Furnace

Note: In some models, two furnaces are installed to provide greater output. When two furnaces are installed, they are in parallel and both will operate at the same time and the same output. Both furnaces will have identical controls.

1. Single-stage valve

2. Modulating valve

3. PCOE expansion board

4. Ignition controller

5. Transformer

6. Combustion blower

7. Burner manifold

8. Collector box

For further information on the optional furnace and its control center, see the Indirect Gas-Fired Heat lOM shipped with the unit.

Dedicated Outdoor Air Unit 15

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