Watts Aerco SmartPlate EV Instruction manual

Heating and Hot Water Solutions
AERCO International, Inc. • 100 Oritani Drive • Blauvelt, NY 10913
USA: T: [phone] • Toll Free: [phone] • AERCO.com
Technical Support • [phone] • Mon-Fri, 8 am - 5 pm EST
© 2021 AERCO
Installation, Operation & Maintenance Manual
SmartPlate®EV
High Pressure Domestic
Hot Water Heaters
Five Double Wall Models:
•
SPDW-EV30
•
SPDW-EV40
•
SPDW-EV60
•
SPDW-EV90
•
SPDW-EV140
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Disclaimer
The information contained in this manual is subject to change without notice
from AERCO International, Inc. AERCO makes no warranty of any kind with
respect to this material, including, but not limited to, implied warranties of
merchantability and fitness for a particular application. AERCO International is
not liable for errors appearing in this manual, not for incidental or
consequential damages occurring in connection with the furnishing,
performance, or use of these materials.

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TABLE OF CONTENTS
GENERAL INFORMATION................................................................................ 5
1.1 WARNINGS & CAUTIONS.....................................................................................................................5
1.2 INTRODUCTION ...................................................................................................................................6
1.3 ELECTRONIC CONTROL SYSTEM II (ECS II) ...........................................................................................7
1.3.1 The Control Box Assembly ...........................................................................................................8
1.3.2 Flow Meter...................................................................................................................................8
1.3.3 Outlet Temperature Sensors .......................................................................................................9
1.3.4 Boiler Water Inlet Temperature Sensor.......................................................................................9
1.4 SmartPlate EV PIPING ASSEMBLIES...................................................................................................10
1.5 3-WAY ELECTRONIC CONTROL VALVE...............................................................................................11
INSTALLATION................................................................................................13
2.1 INTRODUCTION .................................................................................................................................13
2.2 RECEIVING AND UNPACKING ............................................................................................................13
2.3 SITE SELECTION AND PREPARATION .................................................................................................14
2.3.1 Installation Clearances...............................................................................................................14
2.3.2 Setting the Unit..........................................................................................................................15
2.4 HEATING FLUID AND DOMESTIC HOT WATER (DHW) PIPING...........................................................15
2.5 SmartPlate EV & BENCHMARK PLATINUM BOILERS .........................................................................15
2.6 ELECTRICAL WIRING CONNECTIONS .................................................................................................16
2.6.1 Modbus Connection...................................................................................................................18
2.7 PRESSURE RELIEF INSTALLATION.......................................................................................................19
FUNCTIONAL DESCRIPTION..........................................................................21
3.1 INTRODUCTION .................................................................................................................................21
3.2 MECHANICAL OVERVIEW ..................................................................................................................21
3.3 ELECTRONIC CONTROL OVERVIEW ...................................................................................................21
3.4 OVER-TEMPERATURE CONTROL AND SAFETY FEATURES .................................................................22
ADJUSTMENT..................................................................................................25
4.1 INTRODUCTION .................................................................................................................................25
4.2 3-WAY CONTROL VALVE ADJUSTMENT AND WIRING.......................................................................25
4.2.1 3-WAY Control Valve Actuator Installation and Wiring.............................................................26
4.2.2 3-Way Valve Stroke Adjustment................................................................................................28
4.2.3 Zero and Span Calibration..........................................................................................................28
4.3 ELECTRONIC CONTROL SYSTEM ........................................................................................................29
4.3.1 Setpoint Temperature Adjustment............................................................................................29
4.3.2 Over-Temperature Alarm Limit Adjustment..............................................................................31
OPERATION.....................................................................................................33
5.1 INTRODUCTION .................................................................................................................................33
5.2 PRE-OPERATIONAL CHECKS, INITIAL START-UP ................................................................................33
5.3 SHUTTING DOWN THE SYSTEM.........................................................................................................34
SCHEDULED MAINTENANCE.........................................................................37
6.1 INTRODUCTION .................................................................................................................................37
6.2 PLATE PACK LEAKAGE CHECKS ..........................................................................................................37
6.3 OVER-TEMP SWITCH CHECK..............................................................................................................38
6.4 STRAINER INSPECTION AND CLEANING ............................................................................................38
6.5 3-WAY CONTROL VALVE OPERATIONAL CHECK................................................................................39

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6.6 SENSOR CHECKS ................................................................................................................................39
6.7 PERIODIC CLEANING OF HEAT EXCHANGER......................................................................................40
TROUBLESHOOTING......................................................................................41
7.1 INTRODUCTION .................................................................................................................................41
7.2 TROUBLESHOOTING PROCEDURES ...................................................................................................41
CORRECTIVE MAINTENANCE........................................................................47
8.1 INTRODUCTION .................................................................................................................................47
8.2 CORRECTIVE MAINTENANCE.............................................................................................................47
8.2.1 HEAT EXCHANGER MAINTENANCE............................................................................................47
8.2.1.1 HEAT EXCHANGER CLEANING AND DE-SCALING .................................................................48
8.2.1.2 HEAT EXCHANGER REPLACEMENT.......................................................................................48
8.2.2 CONTROL VALVE ACTUATOR REPLACEMENT AND VALVE REMOVAL........................................50
8.2.2.1 3-Way Control Valve Replacement......................................................................................50
8.2.3 STRAINERS..................................................................................................................................52
8.3 Electronic Control System (ECS II) .....................................................................................................53
8.3.1 CONTROL BOX ASSEMBLY COMPONENTS .................................................................................53
8.3.2 TEMPERATURE CONTROLLER REPLACEMENT............................................................................53
8.3.3 OVER-TEMPERATURE SWITCH REPLACEMENT..........................................................................54
APPENDIX A –Modbus Control and Communication..............................................................................55
APPENDIX B –SCHEMATIC.......................................................................................................................63
APPENDIX C –SmartPlate EV PART LISTS ................................................................................................65
APPENDIX D –RECOMMENDED SPARE PARTS........................................................................................70

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GENERAL INFORMATION
1.1 WARNINGS & CAUTIONS
Installers and operating personnel MUST, at all times, observe all safety regulations. The
following warnings and cautions are general and must be given the same attention as specific
precautions included in these instructions. In addition to all the requirements included in this
AERCO Instruction Manual, the installation of units MUST conform with local building codes.
Authorities having jurisdiction should be consulted before installations are made.
IMPORTANT!
This Instruction Manual is an integral part of the product and must be maintained in legible
condition. It must be given to the user by the installer and kept in a safe place for future
reference.
WARNING!
•Fluids under pressure may cause injury to personnel or damage to equipment when
released. Be sure to shut off all incoming and outgoing water shutoff valves. Carefully
decrease all trapped pressures to zero before performing maintenance.
•Before attempting to perform any maintenance on the unit, shut off all electrical inputs to
the unit.
•Electrical voltages 100 to 230 VAC and 24 volts DC may be used in this equipment.
Therefore, the cover on the unit’s power panel (located behind the unit’s front panel) must
be installed at all times, except during maintenance and servicing.
•A single-pole switch must be installed on the electrical supply line of the unit. The switch
must be installed in an easily accessible position to quickly and safely disconnect
electrical service. Do not affix switch to unit sheet metal enclosures.

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1.2 INTRODUCTION
This manual provides detailed coverage for the AERCO SmartPlate®EV line of Water-to-Water
Heaters. All SmartPlate EV models are equipped with an Electronic Control System (ECS II)
and an electronic 3-Way Control Valve. This Control System and Valve combination is used with
all SmartPlate EV models and sizes.
There are five SmartPlate EV Double-Wall Heat Exchanger Water Heater models available:
SPDW-EV30, SPDW-EV40, SPDW-EV60, SPDW-EV90
Figure 1.1 shows the major components and direction of water flow in a SmartPlate EV, shown
enclosure covers removed.
1. Boiler Water Inlet (from boiler)
2. Domestic Hot Water Outlet
3. Boiler Water Outlet (return to boiler)
4. Domestic Hot Water Inlet
5. 3-Way Control Valve and By-Pass Outlet (shown plugged)
6. Heat Exchanger
7. Pressure Relief Valve
8. ECS II, the Electronic Control System
9. Power Box
10. Flow Meter
FRONT-RIGHT VIEW FRONT-LEFT VIEW
Figure 1.1. SmartPlate EV Components and Water Circulation
7
8
9
1
2
3
4
6
5
10

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1.3 ELECTRONIC CONTROL SYSTEM II (ECS II)
All SmartPlate EV models contain identical Electronic Control Systems, referred to as ECS II.
This system contains a Control Box, which includes all of the electronic circuitry for the ECS II.
In addition, it includes several sensors and safety devices which provide temperature and flow
control information to the Control Box circuitry, as shown below. The devices included in the
ECS II are:
•Feed-Forward Flow Meter
•DHW (Domestic Hot Water) Outlet Dual Temperature Sensors (Type J Thermocouples)
•Boiler Water Inlet Temperature Sensor (Type J Thermocouple)
•Over-Temperature Alarm (With Safety Shutdown)
•3-Way Control Valve and By-Pass Outlet
The ECS II includes a Modbus communication option. This option permits the ECS II to be
externally controlled by an Energy Management System (EMS), Building Automation System
(BAS), or a computer supplied by other manufacturers.
The ECS II assemblies and components are described in the following sections.
NOTE:
On preliminary release units the Control Box is shaped differently but has the same
components and functionality.
Figure 1.2. Electronic Control System (ECS II)
CONTROL BOX
INLET AND OUTLET
TEMP SENSORS
3-WAY CONTROL
VALVE
TEMPERATURE
CONTROLLER
OVER-TEMPERATURE
INDICATOR/SWITCH
ENABLE/DISABLE
SWITCH
FLOW METER

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1.3.1 The Control Box Assembly
The front panel on the Control Box contains the following components:
•Temperature Controller: This device is the “brain” of the ECS II, processing data
received from the temperature sensors. Using feed forward and PID (Proportional
Integral Derivative) algorithms, the Temperature Controller provides a 4 to 20 mA control
signal to the Control Valve Actuator, which precisely modulates the Control Valve for
optimum DHW outlet temperature control. The upper display on the front panel of the
Temperature Controller displays the current DHW outlet temperature. The lower display
continuously displays the DHW setpoint temperature currently stored in the Temperature
Controller.
Figure 1.2.1. Temperature Controller
•Over-Temperature Indicator/Switch: This device constantly monitors and displays the
unit’s outlet temperature to ensure it does not exceed the preset high temperature limit.
The over-temperature limit is factory-set 20°F above the unit’s setpoint temperature
specified on the sales order. If an over-temperature condition occurs, this device sounds
an audible alarm and cuts off power to the Control Valve Actuator thereby closing the
Control Valve and shutting off the boiler water flow to the unit.
The Boiler Water inlet temperatures is sensed on the surface of the inlet pipe and is provided for
informational and troubleshooting purposes only.
The Control Box components are housed in a steel enclosure mounted on the top of the unit’s
base. All sensor and control signal connections are made via cable connections at the right side
of the Control Box. External AC power (120 VAC, 60 Hz, 220 VAC 50 Hz or 220V, 60 Hz) is
supplied via the cutout on the right-side of the Control Box.
1.3.2 Flow Meter
A Flow Meter is installed on the domestic cold-water inlet. It senses inlet flow into the unit and
provides a signal to the temperature controller. The Controller uses this signal to calculate the
amount of heat input required from the boiler loop.
DHW OUTLET TEMPERATURE
SETPOINT

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1.3.3 Outlet Temperature Sensors
The Control System includes a Dual Temperature Sensor which is installed in the hot water
outlet of the unit. This sensor contains two identical Type J thermocouples. The first
thermocouple connects directly to the Temperature Controller to provide feedback PID control
for the outlet water temperature. The second thermocouple connects to the Over-Temperature
Indicator/Switch in the Control Box.
1.3.4 Boiler Water Inlet Temperature Sensor
An additional Temperature Sensor (Type J thermocouple) is provided with the Control System.
This Sensor is attached to the unit’s boiler water inlet. This sensor is connected to the
Temperature Controller to provide a real-time indication of the inlet water temperature.

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1.4 SmartPlate EV PIPING ASSEMBLIES
All SmartPlate EV models include a 2” diameter piping assembly. This assembly includes the
following components:
•Flow Meter
•Strainers (Boiler Water & DHW Sides)
•Blow-down Valves
•2” Piping and support brackets
•3-Way Valve
•Heat Exchanger
•DHW Relief Valve
•Boiler Relief Valve –optional
Figure 1.3. SmartPlate EV Piping Assembly plus Other Components
PRESSURE RELIEF
VALVE
ISOLATION BALL
VALVES & STRAINER
HEAT EXCHANGER
3-WAY CONTROL
VALVE
ISOLATION BALL VALVES
POWER BOX
STRAINER WITH
BLOW-DOWN VALVE
CONTROL BOX
RETURN TO
BOILER
DHW
OUTLET
BOILER
WATER INLET
DHW INLET
FLOW METER

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1.5 3-WAY ELECTRONIC CONTROL VALVE
The 3-Way Electronic Control Valve is powered by 24 VAC from the ECS II Control Box. The
Temperature Controller in the Control Box supplies a 4 to 20 mA control signal to precisely
modulate the 3-Way Valve to accurately control the temperature of the DHW output to the
desired setpoint. The Control Valve is shown below. The connection unions have flat face
gaskets that provide the fluid seal.
Figure 1.4. 3-Way Electronic Control Valve
ELECTRONIC
MODULE
HAND LEVER
PORT AB
PORT A
PORT B

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INSTALLATION
2.1 INTRODUCTION
All of the SmartPlate EV Water Heater models are shipped fully assembled and ready for
installation. Therefore, installation will consist of the following tasks:
•Unpack the SmartPlate EV Water Heater from its shipping container.
•Position and secure the unit at the site.
•Install the Pressure Relief Valve.
•On units installed in New York City, install a second Relief Valve on the boiler water intake
piping.
•Connect the hot boiler water piping to the unit.
•Connect the domestic hot water (DHW) piping to the unit.
•Connect external AC power to the ECS II Control Box.
•If desired, connect Modbus control wiring to the Temperature Controller in the ECS II
Control Box.
2.2 RECEIVING AND UNPACKING
Each SmartPlate EV Water Heater is shipped as a single crated unit. The packaged shipping
weight will vary from approximately 500 to 760 pounds, depending on the model ordered.
The unit must be moved with the proper equipment (forklift, pallet jack, etc.) to avoid possible
injury to personnel or damage to the shipping container or unit. The shipping carton should be
inspected for damage incurred during transit prior to signing the bill of lading.
NOTE:
AERCO is not responsible for lost or damaged freight. The freight carrier must be notified
immediately of any damage detected.
Unpack the SmartPlate EV Water Heater from its shipping container taking care not to damage
the unit when cutting away the packaging material.
Remove the package containing the Relief Valve and associated piping.
Remove the bolts securing the unit to its shipping skid and then lift it off the skid and position it
in place. Perform a complete visual inspection of the unit to ensure there is no evidence of
damage.

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2.3 SITE SELECTION AND PREPARATION
Ensure that the site selected for installation of the SmartPlate EV Water Heater includes the
following:
•Access to AC input power at 120 VAC/60 Hz, 220 VAC/50 Hz or 220 VAC/60 Hz, single
phase.
•Close proximity to the boiler to be used as the heating fluid (hot water) source
•If applicable; access to Modbus Network wiring within the prescribed wire lengths (see
section 2.5).
2.3.1 Installation Clearances
The heater must be installed with the prescribed clearances for service as shown in Figure
2.3.1. The minimum clearance dimensions recommended by AERCO are listed below.
However, if local building codes require additional clearances, these codes shall supersede
AERCO’s recommendations.
•Sides: 0 in. (0 cm) –Left side dependent on need of bypass piping
•Front: 24 in. (61 cm)
•Rear: 24 in. (61 cm) –Recommended
•Top: 12 in. (30.5 cm) –Depending on use of elbow piping
All water piping and electrical conduit must be arranged so that it does not interfere with the
removal of any Water Heater assemblies/parts or inhibit service or maintenance of the unit.
Figure 2.3.1. SmartPlate EV Water Heater Clearances
CAUTION!
While packaged, the unit must be moved using a forklift or pallet jack. After unpacking, the unit
can be moved with forklift by inserting the tines through the openings in the sides of the unit's
base. If the unit needs to be lifted, attached lifting eye bolts to the four corners of the base.
FRONT VIEW
OVERHEAD VIEW

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2.3.2 Setting the Unit
The preferred way to lift and move the unit is to lift it with a forklift under the base.
In multiple unit installations, it is important to plan the position of each unit in advance. Sufficient
space for piping connections and future service/maintenance requirements must be taken into
consideration. All piping must include ample provisions for expansion.
2.4 HEATING FLUID AND DOMESTIC HOT WATER (DHW) PIPING
The diameter of the heating fluid (hot boiler water) and DHW piping for all SmartPlate EV
models is 2.0 inches.
CAUTION!
Two pipe wrenches MUST be used when installing boiler water and DHW piping unions to
prevent pipe rotation and avoid leaks.
IMPORTANT!
When SmartPlate EV Water Heaters are shipped from the factory, all four isolation ball valves
(see Figure 1.3) are open.
· CLOSE ALL VALVES DURING INSTALLATION.
·Do not open the valves until instructed to do so in Chapter 5 of this manual.
2.5 SmartPlate EV & BENCHMARK PLATINUM BOILERS
SmartPlate EV units come equipped with a linearized 3-Way Electronic Control Valve, described
in Section 1.4 and shown in Figure 2.5, below. All units are shipped with a factory-installed plug
in the valve’s Port B.
Figure 2.5.SmartPlate EV 3-Way Plug
The way this valve is used depends on how many SmartPlate EV units are at the site:
•Single SmartPlate EV installations: Remove the factory-installed plug from port B by
inserting the hexagonal bar (provided in the loose parts kit) into the plug’s port and rotating
with a pipe wrench. Then, connect a pipe from this port to the upper return inlet on
Benchmark Series Platinum boilers. During operation, the SmartPlate EV unit determines
how much heating load is required to maintain setpoint temperature and provides the
required boiler water flow to the heat exchanger to maintain that temperature. Any
3-WAY VALVE
PLUG IN PORT B

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additional water from the boiler not required to maintain temperature is diverted back to
the boiler via the 3-Way Electronic Control Valve.
•Multiple SmartPlate EV installations: Remove the factory-installed plug from port B
from at least one SmartPlate EV unit. Connect a pipe from this unit to the upper return inlet
on Benchmark Series Platinum boilers. The others may remain plugged if desired, as long
as the flow rate in each bypass line is less than 90 GPM. In all units with the plug in port
B, the 3-Way Electronic Control Valve will operate as a two-way valve.
Note that for installations not utilizing the return-port B (2-way valve operation only), be sure to
provide an alternate (diverting) flow path to the unit for zero-load conditions so as not to dead-
head the pump.
2.6 ELECTRICAL WIRING CONNECTIONS
The SmartPlate EV ECS II Control Box and all other electrical components are installed on the
unit prior to shipment from the factory. As a result, electrical connections to the ECS II consists
of connecting external AC power to the Power Box.
WARNING
The SmartPlate EV is electrically powered. ALWAYS take proper precautions to recognize,
evaluate, and control electricity hazards during installation, programming, use and
service/maintenance. Be sure that power is disconnected from the product when performing
any work with electrical connections.
The system is powered by a single-phase AC voltage of 120–230 VAC, 50-60 Hz. However, if
Modbus Communication is desired, several additional signal lead connections must be made
inside the Control Box. These signal leads will permit the ECS II to be controlled by an external
Energy Management System (EMS), Building Automation System (BAS), or computer. Proceed
as follows:
ELECTRICAL WIRING CONNECTIONS Instructions
1. Remove the front cover from the unit to expose the Power Box.
2. Thread the power cable through one of the cut-outs in the side or rear enclosure panels.
Figure 2.6-1, Power Cable Connection
POWER CABLE
CONNECTION

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ELECTRICAL WIRING CONNECTIONS Instructions
3. Thread the power cable through the cut-out in the side of the Power Box.
Figure 2.6-2, Power Cable Connection
4. Connect the power cable’s wires to the connectors in the Power Box as follows:
Figure 2.6-3, Power Cable Connection
•Black to power
•White to neutral
•Green to ground
NOTE:
Use 14 to 18 AWG wire for AC power wiring connections to the SmartPlate EV Power Box.
POWER CABLE
ACCESS
BLACK CABLE - POWER
WHITE CABLE - NEUTRAL
GREEN CABLE - GROUND

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2.6.1 Modbus Connection
All SmartPlate EV Control Systems includes a Temperature Controller, which is equipped with a
Communications Board that allows connection to Modbus networks. The required signal
connections will depend on the ports available on the Energy Management System (EMS),
Building Automation System (BAS), or Computer being used with the ECS II.
CAUTION!
DO NOT route Modbus communication wiring in the same conduit as power wiring. Attempting
to do so may result in excessive noise on the signal lines. Also, ensure that the RS485 signal
cable connections do not exceed 4,000 feet maximum.
MODBUS WIRING CONNECTIONS Instructions
1. Refer to Table 2-1, below, and connect the appropriate wire leads to the Temperature
Controller terminals listed. Refer to the Temperature Controller pinouts shown in Figure 2.6.1
to locate the required terminals. Also, refer to Appendix A for instructions on how to change
the Temperature Controller Modbus address, a listing of active Modbus data addresses for
the Controller, and how to change the baud rate. In addition, the documents referenced in
this Appendix provide additional communication information related to Modbus.
NOTE:
AERCO recommends that shielded, twisted-pair cable be used for communication wiring.
Examples of suitable wiring are: Belden 9841, 8761, 3105A, or equivalent.
TABLE 2-1. Modbus Communication Signal Connections
TEMP. CONTROLLER
RS485
SIGNAL NAME
PIN NO.
SIGNAL NAME
PIN NO.
COMMON
JD
COMMON
COMMON
RECEIVE
JE
TRANSMIT
A(-)
TRANSMIT
JF
RECEIVE
B(+)

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MODBUS WIRING CONNECTIONS Instructions
Figure 2.6.1. Eurotherm 3504 Temperature Controller Terminal Connection Diagram
2.7 PRESSURE RELIEF INSTALLATION
SmartPlate EV units are shipped with the Pressure Relief Valve assembled.
Pressure Relief Valve and Air Bleeder Valve Installation Instructions
1. Attach a drain pipe to the end of the Pressure Relief Valve and run it to any convenient
drain.
Figure 2.7-1. Pressure Relief Valve Installation
PRESSURE
RELIEF VALVE
ELBOW
NIPPLE

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Pressure Relief Valve and Air Bleeder Valve Installation Instructions
2. If the unit is being installed in New York City only in addition to the steps above you must
install a second Relief Valve (P/N (kits 58202-2 or 58202-3) in the Boiler Water Intake Ball
Valve/Strain combo, as shown in Figure 2.7-2.
Figure 2.7-2. Relief Valve Installation –New York City Option
NOTE:
There is a port on the boiler inlet’s combination valve that can be used to install a boiler side
relief valve. In order to use this port, remove the 1” NPT cap and install the 1” to ¾” busing
and ¾” relief valve found in the spare parts kit (P/N 58202-2 or 58202-3). If needed, use the
¾” nipple and elbow provided in the spare parts kit to provide more space for relief valve
piping.
Bushing, 1” to ¾”
Relief Valve
BOILER WATER INLET
NOTE:
Rotate the Relief Valve so that
the outlet connection to the
drain hose does not interfere
with other components
Relief Valve
Outlet