RenewAire EK Series User manual

EK Series shown
EK Series for Commercial Indoor Applications
EK SERIES Electric Duct Heater
Installation, Operation and Maintenance Manual

1.800.627.44992
EK-Series Electric Duct Heater
ACCESSORY
WARNING
Arc flash and electric shock hazard
Arc flash and electric shock hazard. Disconnect all electric
power supplies, verify with a voltmeter that electric power
is off and wear protective equipment per NFPA 70E before
working within electric control enclosure. Failure to comply can
cause serious injury or death.
Customer must provide earth ground to heater, per NEC, CEC
and local codes, as applicable.
Before proceeding with installation, read all instructions, veri-
fying that all the parts are included and check the nameplate to
be sure the voltage matches available utility power.
The line side of the disconnect switch contains live high-volt-
age.
The only way to ensure that there is NO voltage inside the
heater is to install and open a remote disconnect switch and
verify that power is off with a volt meter. Refer to unit electrical
schematic. Follow all local codes.
CAUTION
CAUTION
Risk of electric shock or equipment damage
Whenever electrical wiring is connected, disconnected or
changed, the power supply to the heater and its controls must
be disconnected. Lock and tag the disconnect switch or circuit
breaker to prevent accidental reconnection of electric power.
Risk of contact with HOT SURFACES
This heater, including the heating elements and their support
structure are extremely hot during operation. Allow sufficient
time for them to cool before working within the cabinet. Use
extreme caution and wear protective gloves and arm protection
when working on or near the heater.

31.800.627.4499
EK-Series Electric Duct Heater ACCESSORY
SAVE THIS MANUAL
UNIT RECORDS
Record information as shown below. In the unlikely event that factory assistance is ever
required, this information will be needed.
Serial Number:
Heater Model No:
Locate the RenewAire unit label, found on the door of the electric duct heater.
NOTE: This information is for purposes of identifying the specific furnace. Unit-specific option
data can then be obtained, as needed, from the Model Number. See Electric Heater Code in this
manual for further details.
TYPICAL ELECTRIC DUCT HEATER LABEL
ELECTRIC DUCT HEATER
MODEL NUMBER
SERIAL NUMBER
SO#
NOTE: This page
is to be completed
by the installing
contractor. The completed
document is to be turned
over to the owner after
start-up.
OWNER INFORMATION
SO Number:

1.800.627.44994
OPTIONS & ACCESSORIES
Specifications may be subject to change without notice.
0
25
50
75
100
125
150
175
200
02500 5000 7500 10000 12500
HEATER CAPACITY -kW
AIRFLOW -CFM
EK Series Heater Capacity
SAFE OPERATING
RANGE
EK SERIES HEATER CAPACITY
ELECTRIC DUCT HEATER SPECIFICATIONS
Heater Type:
Electric Duct Heater
Typical KW Range:
1–175 kW
Standard Features:
A disconnecting magnetic control contactor per
stage or each 48 Amp circuit within a stage
Open-coil element
Staged on/off
Control terminal board
Grounding lugs
Automatic limit switch for primary over-
temperature protection
Manual reset limit switch for secondary over-
temperature protection
Non-adjustable airflow switch
Standard control transformer - 24 VAC
Disconnect switch
Duct thermostat with sensor for on/off control
60-20-20 (Ni/Cr/Fe) C Grade element wire with
nickel-plated terminals
Slip-in mount
No left/right hand
Vertical up/down flow
Voltages & Phase:
Single phase - 120, 208, 240, 277
Three phase - 208, 240, 480, 600
Control Voltage:
24 VAC
Dimensions:
Minimum - 8" x 8" (W x H)
Maximum - 99" x 99" (W x H)
Options:
Flange mount
80-20 (Ni/Cr) A Grade element wire with
stainless steel terminals
Recessed control box 1"
Gasketed cover - dust tight
Power fusing, standard for heaters drawing more
than 48 Amps
2-stage
Electronic step controller (4-stage)
SCR (up to 96 Amps)
SCR Vernier (over 96 Amps)
Pilot light
Accessory:
Room thermostat
Room/duct thermostat-sensor kit for SCR control
Note: Electric duct heater designed for indoor ductwork installation only.
SERIESEK Electric Duct Heater (1-175 kW) Accessory
Download specification at:
renewaire.com/specifications
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
02004006008001000120014001600180020002200
PRESSURE DROP THROUGH HEATER
Static Pressure Drop - Inches of Water
Air Velocity - FPM (1, 2, 3 and 4 - the number of rows of heater coils)
When the number of rows of heater coils is unknown, assume 4.
1
2
3
4
PRESSURE DROP THROUGH HEATER
FLIPPABLE
CAPABILITIES
Unique to the EK series, this unit has the ability
to flip 180°. Additionally, EK heaters features
both vertical up and vertical down airflow.
SLIP-IN
CONSTRUCTION
SHOWN
AIR DUCT
FIGURE: 4
BASE
HEATER
BASE
HEATER
ROTATED
180o
BASE
HEATER
BASE HEATER
FLIPPED 180°
* ONE HEATER- 4
POSITIONS
3
HORIZONTAL DUCT & AIRFLOW
with HORIZONTAL INSTALLATION
AIRFLOW
p
g
VERTICAL DUCT & AIRFLOW
AIRFLOW
AIRFLOW
* SAME HEATER- FOR
VERTICAL DUCTS
AIRFLOW

51.800.627.4499
NOTES: 1. W and H determined by duct size A. For slip-in
W = Duct width minus 1/4 inch H = Duct height minus 1/16 inch
B. flange mount
W and H=Duct size
2. U = (W+H Up to 60"=4 7/8), (61" and over U=6")
(W greater than 36" U=6")
3. BD = 4 1/4, 6, 8 1/2, or 10 1/4 depth of control box depends on the
components required and size of power entry holes
4. Z = (H+2" standard for slip in) (H+4" for flange mount)
5. T = 1" standard 6. M = 1" standard 7. Q = (12" minimum) Size depends on required components.
Consult factory for dimensions
8. F = 9/16" for slip-in type
1" for flange mount
9. R = 1 1/2" when using 4 7/8" U dimension
15/16" when using 6" U dimension
10. N = Q minus R and U
NOTE: R and N dimensional values exchange position for right hand offset.
500 Gould Drive, Cookeville, TN 38506
Phone: [phone] • 1 [phone] • Fax: [phone]
www.tutco.com
TECHNICAL DATA
®
ITEM QTY SERIES KW PH VOLTS STG CTL VLT S/F KW/STG W H Q Z U BD F R N T M
1. W and H determined by duct size A. For slip-in W = Duct width minus 1/4 inch H = Duct height minus 1/16 inch B. flange mount W and H=Duct size 2. U = (W+H Up to 60"=4 7/8), (61" and over U=6") (W greater than 36" U=6") 3. BD = 4 1/4, 6, 8 1/2, or 10 1/4 depth of control box depends on the components required and size of power entry holes
4. Z = (H+2" standard for slip in) (H+4" for flange mount) 5. T = 1" standard 6. M = 1" standard 7. Q = (12" minimum) Size depends on required components. Consult factory for dimensions 8. F = 9/16" for slip-in type 1" for flange mount 9. R = 1 1/2" when using 4 7/8" U dimension 15/16" when using 6" U dimension 10. N = Q minus R and U
Note: R and N dimensional values exchange position for right hand offset.
FORMULAS FOR FIGURING KW AND TEMPERATURE RISE The following fomula may be used to determine the approximate total KW required when the CFM (air volume) and desired temperature rise are known: KW =
DETERMINING THE TEMPERATURE RISE OF A DUCT HEATER The following formula may be used to determine the approximate temperature rise of a duct heater when the KW and CFM are known: T.R. =
CFM X T.R.
3150
KW X 3150
CFM
R
R
F
F
W
W
M*
M*
T*
T*
U
U
Q*
Q*
BD*
BD*
Z*
Z*
N
N
OFFSET LEFT
STANDARD
OFFSET RIGHT
OPTIONAL
H
H
R
R
F
F
W
W
M*
M*
T*
T*
U
U
Q*
Q*
BD*
BD*
Z*
Z*
N
N
OFFSET LEFT
STANDARD
OFFSET RIGHT
OPTIONAL
H
H
TYPE S SLIP-IN
TYPE F FLANGE MOUNT
= Dimensions do not include allowance for
control box cover. Control box cover will be larger than the control box.
*
PRODUCT DIMENSIONS ELECTRIC DUCT HEATER
ABBREVIATIONS W Width H Height

1.800.627.44996
EK-Series Electric Duct Heater
ACCESSORY
TABLE OF CONTENTS
1.0 OVERVIEW 11
1.1 DESCRIPTION .......................................................11
1.2 ELECTRICAL SUPPLY.............................................11
1.3 HEATER CAPACITY IN KILOWATTS .........................12
1.4 HEATER ELEMENTS ..............................................12
1.5 SAFETY FEATURES ...............................................12
1.5.1 Airflow Switch ..................................................................12
1.5.2 Automatic Reset Limit Switch............................................12
1.5.3 Manual Reset Limit Switches ............................................12
1.6 HEATER CONTROL ................................................13
1.7 HEAT RISE............................................................13
1.8 USER INTERFACE .................................................13
2.0 SYSTEM REQUIREMENTS 14
2.1 GENERAL OPERATING REQUIREMENTS..................14
2.2 SIZING AN ELECTRIC DUCT HEATER ......................14
2.3 AMPERAGE DRAW ................................................14
2.4 KW AND TEMPERATURE RISE................................14
2.5 DUCT HEATER TEMPERATURE RISE.......................14
2.6 DETERMINING MAXIMUM HEATER KW...................14
2.7 MINIMUM AIR VELOCITIES ....................................15
3.0 HEATER PLACEMENT 16
3.1 GENERAL .............................................................16
4.0 ELECTRICAL DATA 19
4.1 TYPICAL CONTACTOR POWER CIRCUITRY ..............19
4.2 HEATING ELEMENT WIRING CONFIGURATIONS AND
PROPERTIES ..............................................................19
4.3 HEATER WIRING SCHEMATICS...............................20
4.4 LOW VOLTAGE CONTROL SYSTEM..............................22
4.4.1 Specifications...................................................................22
4.4.2 Limits of Power Output .....................................................22
4.5 LOW VOLTAGE CONTROLS CONNECTION...................23
4.5.1 Interface Module Control Signal Wiring Connection Diagram
.................................................................................................23
4.5.2 Electronic Step Controller or SCR Control ..........................24
4.5.3 Staged Control .................................................................25
5.0 INSTALLATION 26
5.1 PLACEMENT OF THE ELECTRIC DUCT HEATER .......26
5.2 HEATER INSPECTION ............................................26
5.3 DUCT INSTALLATION.............................................27
6.0 OPERATING INSTRUCTIONS 28
6.1 ELECTRICAL REQUIREMENTS................................28
6.2 GENERAL OPERATING REQUIREMENTS..................28
7.0 MAINTENANCE 29
7.1 SERVICE PARTS....................................................29
8.0 FACTORY ASSISTANCE 30

71.800.627.4499
EK-Series Electric Duct Heater ACCESSORY
TABLE OF ILLUSTRATIONS
TABLE OF WIRING SCHEMATICS
Figure 4.3.0 Single Phase On-Off Heater Wiring .....................................................................................20
Figure 4.3.1 Single Phase SCR Heater Wiring .........................................................................................20
Figure 4.3.2 Three Phase On-Off Heater Wiring......................................................................................21
Figure 4.3.3 Three Phase SCR Heater Wiring..........................................................................................21
Figure 4.5.0 Stand Alone Thermostat for Modulating Control ..................................................................23
Figure 4.5.1 DDC BAS for Modulating Control (2-10Vdc)..........................................................................23
Figure 4.5.2 DDC BAS for Modulating Control (4-20mA) .........................................................................23
Figure 4.5.3 Viconics Room Thermostat without Remote Sensor for Modulating Control ..........................24
Figure 4.5.4 Viconics Room Thermostat with Remote Sensor for Modulating Control for Return Air..........24
Figure 4.5.5 Viconics Room Thermostat with Remote Sensor for Modulating Control for Supply Air .........24
Figure 4.5.6 Single Stage Thermostat with Remote Sensor for On/Off Control.........................................25
Figure 4.5.7 2-Stage Thermostat with Remote Sensor for On/Off Control................................................25
Figure 1.1.0 Electric Heater (typical)....................................................................................................... 11
Figure 1.1.1 Control Panel Cover............................................................................................................. 11
Figure 1.1.2 Basic Control Panel............................................................................................................. 11
Figure 1.5.0 Heater Controls Identification ............................................................................................. 12
Figure 1.7.0 Heat Rise Calculation.......................................................................................................... 13
Figure 2.7.0 FPM vs. KW / Ft.2 Chart ...................................................................................................... 15
Figure 3.1.0 Placement: Minimum Airflows............................................................................................. 16
Figure 3.1.1 Placement: Elbow Minimum Requirement ............................................................................ 16
Figure 3.1.2 Placement: Location Requirements ..................................................................................... 16
Figure 3.1.3 Placement: Transition Requirements ................................................................................... 17
Figure 3.1.4 Placement: Downstream Requirements ............................................................................... 17
Figure 3.1.5 Placement: Humidifier Requirements................................................................................... 17
Figure 3.1.6 Placement: Air Filter Requirements ..................................................................................... 17
Figure 3.1.7 Placement: Obstruction Requirements................................................................................. 18
Figure 3.1.8 Placement: Control Box Requirements................................................................................. 18
Figure 3.1.9 Placement: Double Blower Requirements ............................................................................ 18
Figure 4.1.0 Typical Contactor Power Circuitry........................................................................................ 19
Figure 4.2.0 Heating Element Wiring Properties...................................................................................... 19
Figure 5.3.0 Slip-in Heater Installation ...................................................................................................27
Figure 5.3.1 Flange Heater Installation ...................................................................................................27
Figure 5.3.2 Common Installation Approaches........................................................................................27
Figure 7.1.0 Service Parts ......................................................................................................................29
TABLE OF CONTENTS

1.800.627.44998
EK-Series Electric Duct Heater
ACCESSORY
MODEL NUMBER
Heater Type
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
"EK "= Electric Heater (Standard)
DIGIT NUMBER
Digits 1 - 2:
Width in Inches (see Restriction 1)
Digits 4 - 5:
08-99
Mount
Digit 11:
"S" = Slip In (Standard)
"F = Flanged
Element Style
Digit 12:
"C" = Open Coil (Standard)
Element Material
Digit 13:
"C" = 60-20-20 Ni-Cr-Fe with Nickel Plate Terminal Pins (Standard)
"A" = 80-20 Ni-Cr with Stainless Steel Terminal Pins
Airflow Orientation
Digit 14:
"H" = Horizontal (Standard)
"V" = Vertical
Control Box Offset
Digit 15:
"L" = Left Hand (Standard)
"R" = Right Hand
*NOTES:
Digit 3 is not used in this model.
All heaters come with standard features: Disconnect Switch, Air Flow Switch (non adjustable), Control Transformer
Descriptions of feature and options are found in the installation and operation manual.
Restrictions:
1: Width inches entered as a whole number.
2: Height inches entered as a whole number.
3: Heater density should be less than 30kW/ft². DENSITY= HEATER CAPACITY (kW) < 30
(W" x H")/144
4: Heater capacity kW entered as a whole number.
5: Formulas for calculating kW and temperature rise: kW = CFM x ΔT ΔT = kW x 3150
3150 CFM
7: Voltage Codes "1" & "9" only available with Phase Code "1" (Single-Phase).
8: Voltage Codes "4" & "8" only available with Phase Code "3" (Three-Phase).
9: Power Fusing Code "F" required when amperage is >48A. (based on kW and voltage)
10: Control Type Code "D" only available with Stage Code "1" & "2".
11: Control Type Code "E" only available with Stage Code "4".
12: Control Type Code "S" & "V" only available with Stage Code "1", unless amperage is greater than or equal to 96A, then Stage Code "4" is automatically selected.
Voltage (see Restrictions 7 & 8)
Digit 18:
"1" = 120V
"2" = 208V
"3" = 240V
"4" = 480V
"8" = 600V
"9" = 277V
Phase
Digit 19:
"1" = Single-Phase
"3" = Three-Phase
Stage
Digit 21:
"1" = Single (Standard)
"2" = 2-Stage
"4" = 4-Stage
Control Voltage
Digit 22:
"S" = 24VAC
Time Delay
Digit 24:
"-" = None (Standard)
-
Height in Inches (see Restriction 2)
Digits 6 - 7:
08-99
Capacity in kW (see Restrictions 3, 4 & 5)
Digits 8 - 10:
001-175
Control Box Recessed
Digit 16:
"-" = None (Standard)
"R" = Recessed 1"
Power Fusing (see Restriction 9)
Digit 20:
"-" = None
"F" = Fusing
Control Type (see Restrictions 10, 11 & 12)
Digit 23:
"D" = Duct Thermostat with Sensor (Standard)
"E" = Electronic Step Control with Sensor
"S" = SCR (For BAS System)
"V" = SCR with Analog Sensor (0-10Vdc)
Pilot Light
Digit 25:
"N" = None (Standard)
"L" = Light
Control Box Dust Tight
Digit 17:
"-" = None (Standard)
"D" = Dust Tight
ELECTRIC POST HEAT
CONFIGURATION CODE CHART
Each RenewAire Electric Duct Heater is assigned a 25 digit Model Number. The Model Number
can be used to identify the various options as ordered by the customer.
ELECTRIC DUCT HEATER CONFIGURATION CODE
CONFIGURATION CODE

91.800.627.4499
EK-Series Electric Duct Heater ACCESSORY
Heater Type:
EK—(Standard) heater 8"–99" height
and width.
Width:
W—Width of duct ID in inches. For slip-in
type the W dimension is undersized by ¼"
to allow heater to slip into ductwork.
Range 8"–99"
Height:
H—Height of duct ID in inches. For slip-
in type the H dimension is undersized
by 1/16" to allow heater to slip into
ductwork.
Range 8"–99"
Capacity:
KW—Kilowatt rating of heater.
Determined by airflow (CFM) and
temperature rise (rT).
Range 1–175 KW
Mount:
Slip-in (Standard)—heater is installed
through opening cut into side of duct and
the control box is attached to duct.
Flanged (Option)—heater is installed
between two sections of flanged duct and
bolted in place.
Element Style:
Open Coil (Standard)—open coil
resistance wire. Used in most
applications.
Element Material:
60-20-20 NI-CR-FE with nickel plate
terminal pins (Standard)—standard “C”
grade element wire. 60% nickel, 20%
chromium, 20% iron.
80-20 NI-CR with stainless steel terminal
pins (Option)—premium “A” grade
element wire.
80% nickel, 20% chromium.
Airflow Orientation:
Horizontal (Standard)—heater installed
where airflow in ductwork is horizontal
through the heater.
Vertical (Option)—heater installed where
airflow in ductwork is vertical through
the heater. Vertical up and down airflow
available in EK series
Control Box Offset:
Left Hand (Standard)—the control panel is
offset to the left side of the heating elements
as determined when looking into the control
box.
Right Hand (Option)—the control panel is
offset to the right side of the heating elements
as determined when looking into the control
box.
Control Box Recessed (Option):
Recessed 1"—Control box is designed
to extend 1" beyond internally insulated
duct. Heater element width construction is
automatically reduced by 1". Heater element
height construction is automatically reduced
by 2". Recess depth dimension is 1". Only
allowed for internally insulated ducts of 1"
insulation thickness.
Control Box Dust Tight (Option):
Dust Tight—Compression type gasket
installed on control box flanges to seal door
opening. Control box seams are filled to
prevent dust intrusion. Typically specified
when local code requires it.
Voltage and Phase:
Single Phase—120V, 208V, 240V, 277V
3-Phase—208V, 240V, 480V, 600V
Power Fusing:
Required by UL and NEC if amperage is over
48A. Otherwise is an option.
Stage:
Single Stage (Standard)—All heating
elements are energized simultaneously. SCR
control is always single stage.
2-Stage (Option)—Heating capacity is divided
into two sections. Half of the heating capacity
can be energized when less heating is
required. Both stages are energized when full
heating is required. Can be for on/off control.
4-Stage—Heating capacity is divided into
four sections. 4-stage for Electronic Step
Control only.
Control Voltage:
24 VAC (Standard)—secondary voltage
DEFINITIONS FOR CONFIGURATION CODE
CONFIGURATION CODE

1.800.627.449910
EK-Series Electric Duct Heater
ACCESSORY
Control Type:
Duct Thermostat with sensor—standard
thermostat with on/off control. Sensor
is duct mounted. Thermostat must be
programmed by installer for the number
of stages. (Standard)
Electronic Step Control—provides
sequencing control in steps of 4 for duct
heater. Converts analog input signal
into discrete steps or stages. As an
example, if you have a 4-stage heater
the step controller would be 4-stage. For
an analog signal greater than 4Vdc the
first stage would energize, for an analog
signal greater than 6Vdc the first and
second stages would energize, for an
analog signal greater than 8Vdc the first,
second, and third stages would energize,
and for an analog signal at 10Vdc all
stages would energize.
Silicon Controlled Rectifier (SCR)—100%
step-less modulating control. Accepts
0-10Vdc or 4-20mA as control signal.
Utilizes solid state relays (SSR) to switch
current to the heating elements, on a
time-proportioned basis.
SCR Vernier—When SCR control is
selected and the heater is greater than
96A then an SCR vernier control is
implemented. This combines an SCR with
4-stage electronic step control as a cost
effective method for providing modulating
control on heaters greater than 96A.
A SSR is an electronic switching device
similar to an electromechanical relay
(contactor) but has no moving parts
which allows very fast switching of high
current loads without arcing or wearing
out. A heater with an SCR controller must
be installed in such a way as to provide
good ventilation to the heat sink so that
the life of the SSR is prolonged. Over-
heating of an SSR causes it to fail so the
heater must be installed such that the
heat sink is positioned either vertically
on the side of the control cabinet or on
top of the control cabinet—never on the
bottom.
Pilot Light Option:
Light to indicate heater energized. Control
voltage same as transformer secondary
voltage (24 VAC).
Airflow Switch: (Standard)
Non-adjustable pressure switch that
prevents the heater from being energized
when no or very low air flow is present
through the heater. Minimum air flow
pressure is 0.05 in.w.c + .02.
Auto Reset: (Standard)
Automatic reset limit switch for primary
over-temperature protection. Required by
UL.
Manual Reset: (Standard)
Manual reset limit switch for secondary
over-temperature protection. Required by
UL.
Disconnect Switch: (Standard)
Non-fused interlocking switch mounted in
the door of the heater control box. Must
be turned off to open door on control
box. Interrupts power to the heater when
turned off.
Terminal Block: (Standard)
Low voltage control terminal block
included.
Ground Lug: (Standard)
Connection point for grounding field
connected line voltage.
All heaters are designed for zero
clearance.
Control box is constructed of galvanized
steel.
Control box has hinged access door with
interlocking disconnect switch.
All heaters are UL and cUL listed and
tested in accordance with Standard
UL1996.
CONFIGURATION CODE