Greenheck ERCH-20 User manual

Installation, Operation and
Maintenance Manuals
Job Title: TEEN CENTER - LOS ALAMOS
Engineer: ARSED ENGINEERING
Contractor: COMFORT SYSTEMS
Elevation: (ft) 7,320
Date: 09/10/15
MECHANICAL REPRESENTATIVES INC
8322 WASHINGTON PLACE NE
ALBUQUERQUE , NM 87113-1669
US
Phone: [phone]
Fax: [phone]
Email Address: [email protected]
P.O. Box 410 Schofield, WI 54476 [phone] FAX [phone] www.greenheck.com
CAPS 4.18.1634 G:\JOBS\TEEN CENTER - LOS ALAMOS.gfcj Page 1 of 2

Product IOMs
Mark Name Model Name
ERV-1 ERCH
EF-1 ALT. 1 GB
EF-4, EF-2, EF-3 SP
TEEN CENTER - LOS ALAMOS
CAPS 4.18.1634 G:\JOBS\TEEN CENTER - LOS ALAMOS.gfcj Page 2 of 2

®
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 instructions could result in personal injury and/or property damage!
Energy Recovery Ventilator with Heating and Cooling 1
®
Only qualified personnel should install 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,
including environmental. 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 (CE) 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 fan 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.
General Safety Information
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 may be equipped with a compressed
refrigerant system. If a leak in the system should
occur, immediately evacuate and ventilate 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.
WARNING
The roof lining contains high voltage wiring. To
prevent electrocution, do not puncture the interior or
exterior panels of the roof.
Document 476054
Model ERCH
Energy Recovery Ventilator
with Heating and Cooling

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 2
Table of Contents
General Safety Information ...................1
Receiving, Handling and Storage ..............3
Product Overview ...........................4
Optional Subassemblies....................4-5
Installation
Unit Dimensions and Weights ..................6
Curb Outside Dimensions, Recommended
Roof Openings and Curb Weights .............7
Service Clearances and Access Locations .....8-12
Handling ..................................13
Lifting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Roof Curb Mounting ........................14
Optional Piping Vestibule.....................14
Rail Mounting/Layout........................15
Duct Connections ..........................15
Electrical Installation
Procedure.................................16
Field-Provided Disconnect....................17
Discharge Air Temperature Sensor .............17
Typical Control Center Components ............17
Optional Accessory Wiring Schematics..........18
Piping Installation
Optional Gas Piping.........................19
Gas Connections ...........................19
Optional Coil Piping .........................19
Water ..................................19
Direct Expansion .........................19
Condensate Drain Trap ....................20
Heat Pump Piping Sizes & Connections .......20
Evaporative Cooler........................21
Water Supply Locations ..................22
Unit Overview
Basic Unit.................................23
Optional Component Overview
Economizer ...............................23
Frost Control ..............................24
Variable Frequency Drive .....................24
CO2Sensor ...............................24
Phase Monitor .............................24
Rotation Sensor ............................24
Dirty Filter Sensor ..........................24
Microprocessor Control ......................25
Unoccupied Recirculation Damper .............25
Service Outlet..............................25
Vapor Tight Lights ..........................25
Hot Gas Bypass Valve .......................25
Hot Gas Reheat Valve .......................25
Digital Scroll Compressor ....................25
Outdoor Airflow Monitor .....................26
Smoke Detector ............................26
Cooling System Overview
Packaged DX ..............................27
Water-Source Heat Pump (HP) ................27
Start-Up
Warnings .................................29
Special Tools Required ......................29
Start-Up Procedure .........................29
Voltage Imbalance ..........................29
Pre-Start-Up Checklist.......................30
Start-Up Checklist .......................30-31
Optional Accessories Checklist ................32
Start-Up Components
Energy Wheel ..............................33
Fans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33-34
Vibration ..................................34
Hot Gas Bypass Valve .......................34
Optional Start-Up Components
Dirty Filter Switch...........................35
Economizer ............................35-36
Frost Control ..............................36
Outdoor Airflow Monitor .....................37
Evaporative Cooler..........................38
Variable Frequency Drives ................39-40
Routine Maintenance
Maintenance Frequency......................41
Units with Packaged DX .....................41
Units with Heat Pump .......................41
Maintenance Procedures
Lubrication ..............................42
Dampers................................42
Gas Furnace.............................42
Fan Belts ...............................42
Fan Motors..............................42
Fan Wheel & Fasteners ....................42
Bearings ................................42
Internal Filter ............................43
External Filter ............................43
Coils ...................................43
Door Seals ..............................43
Energy Wheel ............................44
Evaporative Cooling .......................45
Troubleshooting
Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Refrigeration Circuit ......................47-50
Energy Wheel ..............................50
Evaporative Cooling......................51-52
Controller Alarms ...........................53
Rotation Sensor ............................53
Digital Scroll ...............................53
Unit Protection Module
......................54
Economizer ...............................54
Reference
Technical Assistance Information ..............54
Additional Installation, Operation and
Maintenance Manuals .....................54
Venting Connection Locations .................55
Maintenance Log ....................Backcover
Our Commitment ....................Backcover

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®3
The unit should be stored at least 3½ in. (89 mm) off the
floor on wooden blocks covered with moisture proof
paper or polyethylene sheathing. Aisles between parts
and along all walls should be provided to permit air
circulation and space for inspection.
OUTDOOR — Units designed for outdoor applications
may be stored outdoors, if absolutely necessary. Roads
or aisles for portable cranes and hauling equipment are
needed.
The fan should be placed on a level surface to prevent
water from leaking into the unit. The unit should be
elevated on an adequate number of wooden blocks so
that it is above water and snow levels and has enough
blocking to prevent it 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 during
Storage
While in storage, inspect fans 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. Every three
months, the fan motor should be energized. If paint
deterioration begins, consideration should be given to
touch-up or repainting. Fans 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 or
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.
Receiving
Upon receiving the product check to make sure all items
are accounted for by referencing the bill of lading to
ensure all items were received. Inspect each crate for
shipping damage before accepting delivery. Notify the
carrier if any damage is noticed. The carrier will make
notification on the delivery receipt acknowledging any
damage to the product. All damage should be noted on
all the copies of the bill of lading which is countersigned
by the delivering carrier. A Carrier Inspection Report
should be filled out by the carrier upon arrival and
reported to the Traffic Department. If damaged upon
arrival, file claim with carrier. Any physical damage to
the unit after acceptance is not the responsibility of
manufacturer.
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.
Handling
Units are to be rigged and moved by the lifting brackets
provided or by the skid when a forklift is used. 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.
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.
INDOOR — 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. Temperatures
should be evenly maintained between 30°F (-1°C)
and 110°F (43°C) (wide temperature swings may
cause condensation and “sweating” of metal parts).
All accessories must be stored indoors in a clean, dry
atmosphere.
Remove any accumulations of dirt, water, ice, or snow
and wipe dry before moving to indoor storage. To avoid
“sweating” of metal parts allow cold parts to reach room
temperature. To dry parts and packages use a portable
electric heater to get rid of any moisture build up. Leave
coverings loose to permit air circulation and to allow for
periodic inspection.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 4
Hot Water / Chilled Water Coils
Water coils can be used for a single purpose such
as heating or cooling, or their function can be
alternated between heating and cooling by changing
the temperature of the water flowing through the coil.
Depending on the application, it may be necessary to
use a glycol mixture to prevent the liquid from freezing.
The water coils are engineered to operate at pressures
up to 250 PSIG and temperatures up to 300°F, but
ancillary equipment such as valves and pumps will often
dictate lower operating temperatures. All water coils
are pressure tested at the factory with 450 PSIG of dry
nitrogen.
Steam Coils
Steam coils are used for heating applications and are
built to operate at pressures of up to 125 PSIG with
a maximum temperature of 353°F. They are pressure
tested with 600 PSIG of dry nitrogen. The most frequent
use of steam coils is for retrofitting or modifying existing
steam heat systems.
Evaporative Cooler
Evaporative cooling modules
include Munters® CELdek®
media (GLASdek® optional)
and a stainless steel frame.
Evaporative cooling media is
12 inches in depth and capable
of 90% cooling effectiveness.
A cooling module in the
exhaust airstream for indirect
evaporative cooling is
standard. For combination
indirect and direct evaporative cooling, an evaporative
section may also be added to the outdoor air stream.
Optional features include an automatic drain and fill with
freeze protection.
Packaged Direct Expansion (PDX)
The DX system comes fully charged from the factory
with refrigerant and is ready for installation upon arrival.
The smaller tonnage units (4-7 tons) contain a single
compressor, allowing for one stage of cooling. Larger
units (8-30 tons) come standard with two compressors
This allows for staging of compressors to meet a wider
range of outdoor air loads with reducing the amount of
cycles per compressor.
Integral Components
All units are provided with an expansion valve, hermetic
scroll compressor(s), liquid line filter drier, high pressure
manual reset cutout, low pressure auto-reset cutout,
time delays for compressor protection, service/charging
valves, moisture indicating sight glass, and optional hot
gas bypass. The compressors also come standard with
a crankcase heater for additional protection.
Product Overview
The model ERCH combines the benefits of energy
recovery and many combinations of supplemental
heating and cooling. Heating sources include indirect
gas, electric, hot water, and water-source heat pump.
Cooling sources include, packaged direct expansion,
split direct expansion, chilled water, and water-source
heat pump. Indirect evaporative and indirect/direct
evaporative cooling is also available in this platform.
This product is specifically designed to process 100%
outdoor air to desired supply conditions. Four housing
sizes provide air flow capacities from 1,000 CFM to
10,000 CFM with external static pressures up to
1.75in.wg.
Optional Subassemblies
Dampers
There are four locations where dampers can be
installed. Low leakage or insulated low leakage
motorized dampers can be added in the outdoor
airstream and/or return airstream. An unoccupied
recirculating air damper is also available. A backdraft
damper is standard in the exhaust hood.
Filters
There is the option of either two-inch thick MERV 8
or MERV 8 and 13 pre-filters in the outdoor airstream
and MERV 8 filters in the exhaust airstream. There are
also permanent washable aluminum mesh filters in the
optional weatherhood.
Wheel Cassette
Coil Section
Exhaust
Weatherhood
Ooutdoor Air
Weatherhood
Return Air
Intake
Electrical Box
Filters
Filters
Indirect Gas Heater
Two-inch thick MERV 8
pleated filters
Motorized Return Air
Damper
Backdraft
Exhaust Damper
Motorized Outdoor
Air Damper
Permanent
Aluminum
Mesh Filters
Two-inch thick MERV 8 or MERV
8 and 13 pleated filters
Motorized Recirculating Air Damper
Model
Tons
Water-Source
Heat Pump
Packaged Direct
Expansion
ERCH-20 4, 5, 6, single stage 4, 5, 6, 7 single stage
ERCH-45 8, 10, 12.5, 15 8, 10, 11, 12.5, 14
ERCH-55 15, 17.5, 20 15, 16, 19
ERCH-90 20, 25, 30 20, 22, 24, 27, 30

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®5
Electric Post-Heaters
The optional post-heater is used as a heat source for
the building and is integrated into the supply airstream.
A temperature sensor (with a field-adjustable set point)
is mounted in the supply airstream after the post-heater
to turn the post-heater on. A SCR heater allows for
an infinite amount of modulating control of the heat to
provide an accurate discharge temperature during the
call for heat.
As standard, the post-heater control panel is not single
point wired to the unit control center. Separate power
must be supplied to the post-heater disconnect (located
in unit control center). Electric heaters are available in
208, 230, 460, or 575 VAC (refer to heater nameplate for
voltage).
Indirect Gas Furnace
An optional indirect gas
furnace may be installed and
provides supplementary heat
to the building. Refer to the
PVF/PVG Indirect Gas-Fired
Heat manuals provided with
the unit. A unit-specific wiring
diagram is located inside the
furnace housing access door.
Outdoor Air Weatherhood
Outdoor air weatherhood will be factory-mounted.
Exhaust Air Weatherhood
The exhaust weatherhood is shipped separately as a
kit with its own instructions. Backdraft dampers are
always included as an integral part of the exhaust hood
assemblies.
Split DX
The unit is equipped with an evaporator coil that
will be connected to a separate condensing unit
(provided by others). Depending on controlling options,
the condensing unit will be controlled by others or
an integral unit microprocessor controller. Piping
components such as thermostatic expansion valve, filter
drier, sight glass, etc., shall be field-provided.
Heat Pump Module
Units with an optional, integral heat pump module
contains hermetic scroll-type compressor(s), a coaxial
refrigerant-to-water heat exchanger(s), refrigerant flow
reversing valve(s), expansion valve(s), liquid line filter
drier, high pressure manual reset cutout, crankcase
heater(s) and various sensors, service ports and safety
devices. The heat pump is intended to be connected to
an external water source such as a water cooling tower,
boiler, or a geothermal source. The module is piped
to the airside coil located in the supply airstream and
optionally to a reheat coil that will control humidity. The
location of components in the module will vary.
Control circuitry and the
Unit Protection Module
(UPM) for the heat pump
will be provided by the
factory. The UPM is a
printed circuit board and
has LED fault indicator
lights to indicate various
alarm conditions and also
power status. A unit-
specific schematic for
electrical circuits is located in the control center and
another unit-specific schematic for heat pump circuitry
and UPM are located in the heat pump module.
Unit Protection Module
(UPM)
Refrigerant
Reversing
Valves
Water Intake
and Discharge
Connections
Coaxial
Refrigerant-
to-Water Heat
Exchangers
High Efficiency
Scroll Type
Compressors
Heat Pump Module

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 6
Unit Dimensions and Weights
Installation
Model
Overall Exterior Dimensions Approximate
Weight
(lbs)
Configuration Length Width Height Exhaust
Hood
Outdoor Air
Hood
ERCH-20
Heating Only 76.2
54.3 54.2 20.8 17.7
1550
Cooling Coil* 96.2 1825
PDX
108.2
2350
WSHP 2375
Evap Cooling 1800
ERCH-45
Heating Only 84.3
64.4 70.2 20.7 21.7
2325
Cooling Coil* 104.3 2725
PDX
119.3
3675
WSHP 3775
Evap Cooling 2900
ERCH-55
Heating Only 97.5
75.2 71 23.6 21.7
3000
Cooling Coil* 116.5 3475
PDX
133.5
4125
WSHP 4725
Evap Cooling 3325
ERCH-90
Heating Only 109.5
94.5 89 25.5 26.7
4300
Cooling Coil* 129.5 5050
PDX
151.5
6325
WSHP 6450
Evap Cooling 5400
*With or without heat.
PDX = Packaged Direct Expansion
WSHP = Water-Source Heat Pump
All dimensions are in inches. Unit weights assume rooftop configuration with weatherhood, filters, outdoor air damper and
heating or cooling options (where applicable) including but not limited to: a six row dx coil, integral condensing section and
an indirect gas-fired furnace. The approximate weight (lbs) is assuming all possible accessories are added per housing and
may vary by 10% depending on unit.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®7
Model Configuration
Outside
Curb
Dimensions
Recommended
Roof
Openings
Optional
Piping
Vestibule
12 inch
Curb
Weight
12 inch
Curb
Weight
with Piping
Vestibule
Curb
weight
only
Curb Weight
with Piping
Vestibule
Length Width A B C D Adder per inch
ERCH-20
Heating Only 71.8 49.9 28.3
43.5 30
12.3 134 157 +6.9 +8.3
Cooling Coil* 91.8 49.9 32.8 147 179 +7.7 +9.5
PDX
103.8 49.9 42.5 166
199
+8.3
+10.1
WSHP NA NA NA
Evap Cooling 28.3
ERCH-45
Heating Only 79.9 60 31.8
54.8 35.1
12.3 157 180 +8.0 +9.4
Cooling Coil* 99.9 60 32.8 170 202 +8.8 +10.6
PDX
114.9 60 43.8 195
228
+9.5
+11.4
WSHP NA NA NA
Evap Cooling 31.8
ERCH-55
Heating Only 93.1 70.8 38.3
63.5 41.8
12.3 184 207 +9.3 +10.7
Cooling Coil* 112.1 70.8 32.8 196 228 +10.1 +11.9
PDX
129.1 70.8 57.8 228
260
+10.9
+12.7
WSHP NA NA NA
Evap Cooling 38.3
ERCH-90
Heating Only 105.1 90.1 39.1
79.4 51.1
12.3 231 254 +11.2 +12.6
Cooling Coil* 112.1 70.8 32.8 196 228 +12 +13.8
PDX
147.1 90.1 61.4 291
323
+13.1
+14.9
WSHP NA NA NA
Evap Cooling 39.1
*With or without heating.
PDX = Packaged Direct Expansion
WSHP = Water-Source Heat Pump
All dimensions are in inches. All weights are in pounds. Various curb heights are available, use the adder per inch column to
determine the weights above 12 inches.
Curb Outside Dimensions, Recommended Roof Openings and Curb Weights
Curb
Height
1/2 inch
1.63
inches
1.9 inches
Unit Base
Curb Duct
Adaptor
1 inch
Curb
1-inch Foam Insulation
Curb Cap Details for Factory-Supplied Roof Curbs
SUPPLY AIR
DISCHARGE
RETURN AIR INTAKE
OPTIONAL
PIPING VESTIBULE
A
B
L
W
26.1 inches
C D
Installation

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 8
INDIRECT GAS FURNACE
ELECTRICAL BOX
EXHAUST FILTERS
OUTDOOR AIR FILTERS
EXHAUST AIR
WEATHERHOOD
WHEEL CASSETTE
OUTDOOR
WEATHERHOOD
HEATING COIL
A
52 inches
CLEARANCE WITH
IG HEATER
0 inches
CLEARANCE WITHOUT
IG HEATER
ACCESS DOOR
B
ACCESS DOOR
*CASSETTE REMOVAL
ACCESS DOOR
36 inches
ACCESS DOOR
PIPING VESTIBULE
(OPTIONAL)
ACCESS DOOR
*Cassette removal only available
on housing sizes 20 and 45. Model A (in.) B (in.)
ERCH-20 48 36
ERCH-45 64 42
ERCH-55 42 42
ERCH-90 42 48
Service Clearances / Access Panel - Heating Only
Units require minimum clearances for access on all sides for routine maintenance. Filter replacement, drain pan
inspection and cleaning, energy wheel cassette inspection, fan bearing lubrication and belt adjustment are examples
of routine maintenance that must be performed. Blower and motor assemblies, energy recovery wheel cassette, coil
and filter sections are always provided with a service door or panel for proper component access.
Drawing shows both heating coil and indirect gas furnace options. Electric heat is also available. Only one can
be selected.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®9
Service Clearances / Access Panel - Cooling Coil (with or without heating)
Units require minimum clearances for access on all sides for routine maintenance. Filter replacement, drain pan
inspection and cleaning, energy wheel cassette inspection, fan bearing lubrication and belt adjustment are examples
of routine maintenance that must be performed. Blower and motor assemblies, energy recovery wheel cassette, coil
and filter sections are always provided with a service door or panel for proper component access.
EXHAUST FILTERS
OUTDOOR AIR FILTERS
WHEEL CASSETTE
OUTDOOR
WEATHERHOOD
COOLING COIL
INDIRECT GAS FURNACE
ELECTRICAL BOX
HEATING COIL
A
48 inches
52 inches
B
ACCESS DOOR
ACCESS PANEL
*CASSETTE REMOVAL
CLEARANCE WITH
IG HEATER
ACCESS DOOR
PIPING VESTIBULE
(OPTIONAL)
0 inches
CLEARANCE WITHOUT
IG HEATER
36 inches
CLEARANCE
WITH
VESTIBULE
CLEARANCE
WITHOUT
VESTIBULE
ACCESS DOOR
ACCESS DOOR
ACCESS DOOR
*Cassette removal only available
on housing sizes 20 and 45. Model A (in.) B (in.)
ERCH-20 48 36
ERCH-45 64 42
ERCH-55 42 42
ERCH-90 42 48
EXHAUST AIR
WEATHERHOOD
Drawing shows both heating coil and indirect gas furnace options. Only one can be selected.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 10
Service Clearances / Access Panel - Integral Air-Cooled Packaged DX
Units require minimum clearances for access on all sides for routine maintenance. Filter replacement, drain pan
inspection and cleaning, energy wheel cassette inspection, fan bearing lubrication and belt adjustment are examples
of routine maintenance that must be performed. Blower and motor assemblies, energy recovery wheel cassette, coil
and filter sections are always provided with a service door or panel for proper component access.
HEATING COIL
COOLING COIL
EXHAUST FILTERS
OUTDOOR AIR FILTERS
WHEEL CASSETTE
OUTDOOR
WEATHERHOOD
ELECTRICAL BOX
HGRH COIL
COMPRESSORS
EXHAUST AIR
WEATHERHOOD
A
48 inches
B
ACCESS DOORS
ACCESS PANEL
*CASSETTE REMOVAL
ACCESS DOOR
PIPING VESTIBULE
(OPTIONAL)
36 inches
CLEARANCE
WITHOUT
VESTIBULE
ACCESS DOOR
CONDENSING SECTION
CLEARANCE
WITH
VESTIBULE
ACCESS PANEL
42 inches
ACCESS PANEL
ACCESS PANEL
MINIMUM
ACCESS DOOR
*Cassette removal only available
on housing sizes 20 and 45. Model A (in.) B (in.)
ERCH-20 48 36
ERCH-45 64 42
ERCH-55 42 42
ERCH-90 42 48
Drawing shows both heating coil and indirect gas furnace options. Electric heat is also available. Only one can
be selected. Optional hot gas reheat coil also shown, available with split or packaged DX.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®11
Service Clearances / Access Panel - Water-Source Heat Pump
Units require minimum clearances for access on all sides for routine maintenance. Filter replacement, drain pan
inspection and cleaning, energy wheel cassette inspection, fan bearing lubrication and belt adjustment are examples
of routine maintenance that must be performed. Blower and motor assemblies, energy recovery wheel cassette, coil
and filter sections are always provided with a service door or panel for proper component access.
EXHAUST FILTERS
OUTDOOR AIR FILTERS
EXHAUST AIR
WEATHERHOOD
WHEEL CASSETTE
OUTDOOR
WEATHERHOOD
HEATING AND COOLING COIL
ELECTRICAL BOX
HGRH COIL
HEAT PUMP
A
B
ACCESS DOORS
ACCESS PANEL
*CASSETTE REMOVAL
ACCESS DOOR
36 inches
ACCESS DOOR
ACCESS PANEL
ACCESS DOOR
42 inches
ACCESS DOOR
*Cassette removal only available
on housing sizes 20 and 45.
Model A (in.) B (in.)
ERCH-20 48 36
ERCH-45 64 42
ERCH-55 42 42
ERCH-90 42 48
Drawing shows optional hot gas reheat coil.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 12
Service Clearances / Access Panel - Evaporative Cooling
Units require minimum clearances for access on all sides for routine maintenance. Filter replacement, drain pan
inspection and cleaning, energy wheel cassette inspection, fan bearing lubrication and belt adjustment are examples
of routine maintenance that must be performed. Blower and motor assemblies, energy recovery wheel cassette, coil
and filter sections are always provided with a service door or panel for proper component access.
EXHAUST FILTERS
OUTDOOR AIR FILTERS
EXHAUST AIR
WEATHERHOOD
WHEEL CASSETTE
OUTDOOR
WEATHERHOOD
INDIRECT GAS FURNACE
ELECTRICAL BOX
INDIRECT
EVAP
DIRECT
EVAP
B
*CASSETTE REMOVAL
ACCESS DOOR
ACCESS DOOR ACCESS DOOR ACCESS DOOR
36 inches
ACCESS DOOR ACCESS DOORS
52 inches
CLEARANCE WITH
IG HEATER
0 inches
CLEARANCE WITHOUT
IG HEATER
A
*Cassette removal only available
on housing sizes 20 and 45. Model A (in.) B (in.)
ERCH-20 48 36
ERCH-45 64 42
ERCH-55 42 42
ERCH-90 42 48
Drawing shows optional indirect gas furnace. Electric heat is also available. Only one can be selected.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®13
Lifting
WARNING
All factory-provided lifting lugs must be used when
lifting the units. Failure to comply with this safety
precaution could result in property damage, serious
injury, or death.
Handling
While this unit was constructed with quality and
dependability in mind, damage still may occur during
handling of the unit for installation. Exercise extreme
caution to prevent any damage from occurring to the
refrigerant system. This unit could contain a system
pressurized with refrigerant that, if damaged, 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.
The system design and installation should follow
accepted industry practice, such as described in
the ASHRAE Handbook. Adequate space should be
left around the unit for piping coils and drains, filter
replacement, and maintenance. Sufficient space should
be provided on the side of the unit for routine service
and component removal should that become necessary.
1. Before lifting, be sure that all shipping material has
been removed from unit.
2. To assist in determining rigging requirements,
weights are provided in the Installation, Unit
Dimensions and Weights section of this manual.
3. Unit must be lifted by all lifting lugs provided on
base structure.
4. Rigger to use suitable mating hardware to attach to
unit lifting lugs.
5. Spreader bar(s) must span the unit to prevent
damage to the cabinet by the lift cables.
6. Always test-lift the unit to check for proper balance
and rigging before hoisting to desired location.
7. Never lift units by weatherhoods.
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 curb prior to lifting
the unit and setting on curb.
11. Do not use fork lifts for handling unit.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 14
Roof Curb Mounting
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.
Position the unit roof opening such that the supply
discharge and exhaust inlet of the unit will line up with
the corresponding ductwork. Be sure to allow for the
recommended service clearances when positioning
opening.
Do not face the outdoor air intake of the unit into
prevailing wind and keep the intake away from any other
exhaust fans. Likewise, position the exhaust discharge
opening away from outdoor air intakes of any other
equipment.
1. Factory-Supplied Roof Curbs: Roof curbs are
Model GKD, which are shipped in a knockdown kit
(includes duct adapter) and require field assembly
(by others). Assembly instructions are included with
the curb.
2. Install Curb: Locate curb over
roof opening and fasten
in place. Reference
Installation, Curb
Outside Dimensions,
Recommended
Roof Openings
and Weights in this
manual. 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 as required to
level.
3. Install Ductwork: Installation of all ducts should
be done in accordance with SMACNA and AMCA
guidelines. Duct adapter 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 is level. Gasketing (by others) needs
to be installed to curb creating a seal between the
ductwork and the base of the unit.
5. 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.
Optional Piping Vestibule
Insulated enclosure that is mounted externally to the
unit in order to protect the water supply and return
piping. Not available in models with water-source heat
pump or evaporative cooling.
Heating Only
Supply Blower
Access Door
Cassette/Filter
Access Door
Outdoor Air
Weatherhood
Exhaust Blower
Access Door
Piping
Vestibule
Supply Blower
Access Door
Drain Pan
Connection
Cassette/Filter
Access Door
Outdoor Air
Weatherhood
Exhaust Blower
Access Door
Piping
Vestibule
Cooling Coil (with or without heating) or PDX
Configuration
Unit Size Heating Only Cooling Coil
ERCH-20 130 190
ERCH-45 160 225
ERCH-55 160 225
ERCH-90 190 265
All weights are in pounds.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®15
R
o
t
a
t
i
o
n
Length of Straight Duct
GOOD
Ductwork Connections
Examples of poor and good fan-to-duct connections
are shown. Airflow out of the fan should
be directed straight or curve the
same direction as the
fan wheel rotates. Poor
duct installation will result
in low airflow and other
system effects.
R
o
t
a
t
i
o
n
POOR
ERCH-20 Recommended Duct Size
Intake Duct Size Discharge 9-9 Blower 10-6 Blower
OIE 22 x 26 SDE 16 x 16 16 x 16
OIT 24 x 20 SDS 16 x 16 16 x 16
RIE 16 x 32 SDT 16 x 16 16 x 16
RIS 18 x 30 SDT/IG 28 x 24 28 x 24
RIB 16 x 32 SDB 12 x 14 12 x 14
RIT 16 x 32 EDE 16 x 16 16 x 16
EDT 16 x 16 16 x 16
EDS 16 x 16 16 x 16
ERCH-45 Recommended Duct Size
Intake Duct Size Discharge 12-8 Blower
12-12 Blower 9-9 Blower
OIE 28 x 36 SDE 20 x 20 16 x 16
OIT 34 x 24 SDS 20 x 20 16 x 16
RIE 24 x 40 SDT 20 x 20 16 x 16
RIS 26 x 32 SDT/IG 28 x 28 28 x 28
RIB 20 x 48 SDB 16 x 18 16 x 18
RIT 28 x 30 EDE 20 x 20 16 x 16
EDT 20 x 20 16 x 16
EDS 20 x 20 16 x 16
ERCH-55 Recommended Duct Size
Intake Duct Size Discharge 12-12 Blower 15-15 Blower
OIE 32 x 52 SDE 20 x 20 28 x 28
OIT 40 x 28 SDS 20 x 20 28 x 28
RIE 30 x 40 SDT 20 x 20 28 x 28
RIS 30 x 38 SDT/IG 38 x 30 38 x 30
RIB 20 x 54 SDB 16 x 18 18 x 20
RIT 30 x 40 EDE 20 x 20 28 x 28
EDT 20 x 20 28 x 28
EDS 20 x 20 28 x 28
ERCH-90 Recommended Duct Size
Intake Duct Size Discharge 15-15 Blower 18-18 Blower
OIE 34 x 64 SDE 28 x 28 32 x 32
OIT 34 x 50 SDS 28 x 28 32 x 32
RIE 32 x 60 SDT 28 x 28 32 x 32
RIS 40 x 40 SDT/IG 34 x 34 34 x 33
RIB 22 x 74 SDB 18 x 20 20 x 24
RIT 40 x 40 EDE 28 x 28 32 x 32
EDT 28 x 28 32 x 32
EDS 28 x 28 32 x 32
All dimensions shown in inches.
• Recommended duct sizes are based on velocities across the cfm
range of each model at approximately 800 feet per minute (FPM) at
minimum airflow and up to 1600 fpm at maximum airflow.
• Recommended duct sizes are only intended to be a guide and
may not satisfy the requirements of the project. Refer to plans for
appropriate job specific duct size and/or velocity limitations.
Inlet/Outlet Descriptions
Code Description Code Description
OIE Outdoor Air Intake End SDT Supply Discharge Top
OIT Outdoor Air Intake Top SDT/IG Supply Discharge Top w/IG
RIE Return Air Intake End SDS Supply Discharge Side
RIS Return Air Intake Side SDB Supply Discharge Bottom
RIB Return Air Intake Bottom EDE Exhaust Discharge End
RIT Return Air Intake Top EDT Exhaust Discharge Top
SDE Supply Discharge End EDS Exhaust Out Side
Rail Mounting
Unit Size A B
ERCH-20 5.0 41.0
ERCH-45 7.0 41.9
ERCH-55 5.5 53.0
ERCH-90 6.0 59.0
All dimensions are in inches.
Rail Mounting / Layout
1. Rails designed to handle the weight of the unit
should be positioned as shown on the diagram (rails
by others).
2. Make sure that rail positioning does not interfere with
the supply air discharge opening or the exhaust air
intake opening on the unit. Avoid area dimensioned
“B” below.
3. Rails should run the width of the unit and extend
beyond the unit a minimum of 12 inches on each
side.
4. Set unit on rails.
BA

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 16
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 Electrical 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 105°C, except for an
energy cut-off or sensor lead wire which must be rated
to 150°C.
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.
WARNING
If unit is equipped with a microprocessor, terminals
Y1, Y2 and W1 cannot be wired to a thermostat.
Wiring to these terminals will bypass unit’s internal
safeties.
Electrical Installation 1. 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.
2. 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.
3. Provide the Opening(s) for the Electrical
Connections
Electrical openings vary by unit size and arrangement
and are field-supplied.
4. 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.
5. 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.
6. 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.
If unit is equipped with a microprocessor, terminals Y1,
Y2 and W1 cannot be wired to a thermostat. Wiring to
these terminals will bypass unit’s internal safeties.
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.
The low voltage control circuit is 24 VAC and control
wiring should not exceed 0.75 ohms. If wire resistance
exceeds 0.75 ohms, an isolation 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.

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling
®17
Typical Control Center Components with
Microprocessor Control
Individual components and locations will vary.
1. Main disconnect (non-fusible, lockable)
2. Motor starter - outdoor air fan
3. Motor starter - exhaust air fan
4. Motor contactor - energy wheel
5. 24 VAC control transformer
6. 24 VAC terminal strip
7. Fuses for blower motors
8. Grounding lug
9. Distribution block
10. Compressor fuse blocks
Optional Components
11. Microprocessor controller
12. Dirty filter pressure switches
13. GreenTrol®
14. Frost control pressure switch
15. Energy recovery wheel VFD
16. Compressor contactors
17. Condenser fan contactors
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.
Discharge Air Temperature Sensor
Without Indirect Gas Furnace
For units without an indirect gas furnace, the discharge
air temperature sensor is factory-mounted in the blower
discharge section of the unit behind the blower cut off
plate.
With Indirect Gas Furnace
For units with an indirect gas furnace, the discharge
air temperature sensor is to be
field-installed prior to unit start
up at least three duct diameters
downstream of the heat exchanger
or where good mixed average
temperature occurs in the ductwork.
The discharge air sensor is shipped
loose and can be found in the unit’s
control center. See the unit-specific
wiring diagram for connection locations.
WARNING
Discharge air temperature sensor is to be field-
installed prior to unit start-up on units with an indirect
gas furnace.
1
2
34
5
7 7
8
9
10 10
6
11
12
13
14
15
16 16
17 17

General Description - NOT model specificEnergy Recovery Ventilator with Heating and Cooling ® 18
W1
12
7
6
Y2
Y1
G
C
R
TERMINAL BLOCKS IN
UNIT CONTROL CENTER
TIMER
BLACK BLUE
RED
(CAPPED)
7-Day Timer
Optional Accessory Wiring Schematics
Remote Panel
The remote panel is available with a number of different
alarm lights and switches to control the unit. The remote
panel ships loose and requires mounting and wiring in
the field. The remote panel is available with the following
options:
• Unit on/off switch
• Unit on/off light
• 7-day time clock
• Hand/off/auto switch
• Dirty filter light
• Economizer light
• Frost control light
• Wheel rotation sensor light
NC C
NC C
NO
NO DIRTY FILTER
EXHAUST DIRTY
FILTER SWITCH
SUPPLY DIRTY
FILTER SWITCH
HOT COMMON
Dirty Filter Indicator
(Powered by others)
A
W1
12
7
6
Y2
Y1
G
C
R
UNIT ON/OFF
COOL STAGE 1 / ECONOMIZER
COOL STAGE 2
UNOCCUPIED RECIRCULATION
S1
S6
S7
S4
S5
HEAT
TERMINAL BLOCKS IN
UNIT CONTROL CENTER
Unit Interfacing Terminals
Heating/Cooling Switches and Night Setback Switch/
Timer
W1
12
7
6
Y2
Y1
G
C
R
NC C
NC C
NO
NO
UNIT ON/OFF
FROST CONTROL
ECONOMIZER
WHEEL ROTATION
DIRTY FILTER
ON
OFF
AUTO *
* -- BMS, TIMECLOCK,
TERMINAL BLOCKS IN
UNIT CONTROL CENTER
ON/OFF/AUTO SWITCH ALLOWS THREE MODES OF OPERATION
"ON" - UNIT IS TURNED ON MANUALLY
"OFF" - UNIT IS TURNED OFF MANUALLY
"AUTO" - UNIT IS CONTROLLED VIA SCHEDULER OF BMS, TIMECLOCK, TSAT, ETC.
TSTAT, RTU, ETC.
EXHAUST DIRTY
FILTER SWITCH
SUPPLY DIRTY
FILTER SWITCH
On/Off/Auto Switch & Indictor Light Wiring