Electric Duct Heater
Specification and Installation Instructions
Heater-manual-170427 1
Nomenclature:
READ AND SAVE THESE INSTALLATION INSTRUCTIONS
Technical data
Model C
Open Coil Elements
Models T or F
Tubular Elements
Maximum inlet air temperature
95˚F (35˚C)
81˚F (27˚C)
Maximum outlet air temperature
200˚F (93˚C)
Minimum distance from obstacle or
obstruction in duct
3x duct diameter upstream and downstream of electric heater
Inlet bushing
2 knock out 7/8’’ (22.2mm) or 1 ⅜’’ (34.9mm)
Control signal
Signal pneumatic or electric - On/Off or modulating
See Electric diagram
Air flow direction
Horizontal or Vertical (refer to name plate)
Contact delay (ON/OFF stage(s))
ON: 1 minute; OFF: 30 seconds
Voltage
See the name plate
Current
Power
Control voltage
Minimum air velocity
Ensure minimum air flow – as marked on name plate.
Caution, Risk of malfunction, In case of alteration (drilling holes or other) to the electrical compartment, ensure proper
protection of all electrical components installed. Chips may cause short circuit or affect operation of electrical components.
Caution, Risk of damage and malfunction, Ensure minimum air flow, insufficient airflow will lead to opening of mechanical air
flow switch (PDN or PDA) or electronic air flow switch sensors (EAS) and automatic thermal cut-out. This may damage heating
elements and controls.
Important, direction of installation (refer to arrow on name plate) must be respected. Failure to do so will impair proper operation
of thermal cut-out and/or cause overheating of solid state relay(s).
Caution, Risk of malfunction, Do not proceed with modification or alteration to internal electric connection or component of the
electric heater. Any non-authorized modification will void the warranty.
D F H00IC
C: Open coil element
T: Tubular element
F: Finned tubular element
0: No screen left of the heater
1: Screen left of the heater
0: No screen right of the heater
1: Screen right of the heater
H: Horizontal air flow
V: Vertical air flow
I: Slip in type
F: Flange type
!
Features:
Zero clearance construction
Horizontal or Vertical air flow
Standard control panel door with removable hinges
Approved to CSA and UL standards
Electric Duct Heater
Specification and Installation Instructions
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1 Dimensions
Slip in type - I
Flange type - F
Standard
With round adapter
2 Installation Tips
2.1 Air flow condition to avoid:
Minimum distance for the conditions below is 3 times the duct diameter.
Electric heater too close to Fan.
Avoid any abrupt transition after a fan.
Electric heater too close to filter.
Electric heater too close to elbow.
Electric heater too close to transition.
Heat sink only on
modulating electric heater
C
D
1 ½'’
(38mm)
1'’
(25.4mm)
Heat sink only on
modulating electric heater
B
A
W - 0.25'
(6.4mm)
H - 0.25'’
(6.4mm)
Heat sink only on modulating electric heater
B
W
1'’ (25.4mm)
H
1'’
(25.4mm)
1'’
(25.4mm)
A
C
D
1 ½'’
(38mm)
1'’
(25.4mm)
Heat sink only on modulating electric heater
W
B
A
H
1'’ (25.4mm)1'’ (25.4mm)
1'’
(25.4mm)
1'’
(25.4mm)
Heat sink only on
modulating electric heater
C
D
2'’
(51mm)
2'’
(51mm)
1 ½'’
(38mm)
1'’
(25.4mm)
Heat sink only on
modulating electric heater
3x duct
diameter
Overheat
Fan
d
3x duct
diameter
Overheat
Filter
3x duct
diameter
Overheat
9
0
°
e
l
b
o
w
3x duct
diameter
Overheat
d
Electric Duct Heater
Specification and Installation Instructions
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2.2 Minimum clearance to access control panel
Caution, for safety reasons, minimum clearance to access control panel must respect local electric code.
Slip-in type electric heater - Type I
Flange type electric heater - Type F
(with or without round adapter)
Provide a minimum clearance equal to W + C + 3’’ (76mm).
Provide a minimum clearance equal to C + 3’’ (76mm).
Caution, Risk of electric shock and burns. A minimum distance of 39’’ (1m) must be maintained between heating section
and any opening or access door in the duct. This applies to all types of heaters. If such distance cannot be maintained, a
protective guard (C22.2 No.155 section 4.1.8) must be installed to protect personnel from contact to heating elements and
bare live parts.
3 Handling
Warning, Risk of failure or malfunction. Do not operate electric heater if heating elements have been damaged during
transport or handling.
Protective packaging must be kept until installation.
Electric heater must be handled with care, particularly for the Open Coil electric heater.
4 Mechanical installation
Caution, Risk of damage and malfunction, Do not block air flow to heating elements, insufficient airflow may damage
heating elements and controls.
Important, direction of installation (refer to arrow on name plate) must be respected. Failure to do so will impair proper
operation of thermal cut-out and/or cause overheating of solid state relay(s),
Flange type electric heater - Type F
With round adapter option
1) Position electric heater in front of the duct flange.
2) Secure electric heater to the duct by using metal screws or
bolts through the duct flanges.
3) If necessary, install supports to maintain the electric heater.
1) Insert electric heater between the two sections of the round
duct.
2) Secure electric heater by using metal screws through round
flanges.
3) If necessary, install supports to maintain the electric heater.
Slip-in type electric heater - Type I
1) Cut an opening in the duct.
Allow ¼’’ (6.3mm) more than the frame width ‘’D’’.
2) Insert electric heater through the opening.
3) Secure electric heater onto the duct using metal screws.
2 flanges of 1’’ (25.4mm) are provided on each side of control
panel.
4) If necessary, re-enforce the duct rigidity by installing
appropriate support(s).
!
Minimum clearance
=
Duct Width (W)
+
Cont. Panel Width (C)
+
3'’ (76mm)
No obstruction
in this area
C
W
39" (1 m)
39" (1 m)
No access door
in this area
No access door
in this area
Minimum
clearance
=
Cont. Panel Width (C)
+
3'’ (76mm)
No obstruction
in this area
C
39" (1 m)
39" (1 m)
No access door
in this area
No access door
in this area
!
!
!
Electric Duct Heater
Specification and Installation Instructions
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5 Electrical Installation
DANGER: Risk of electric shock. Disconnect all supplies before working on any circuit.
CAUTION: Risk of malfunction. Use only copper wires suitable for 221˚F (105˚C).
CAUTION: Electric installation must be done by a qualified electrician and must conform to local electrical codes.
CAUTION: If a disconnect switch and/or fuses have not been supplied on the control panel of the electric heater,
disconnect switch and/or fuses must be installed on supply.
CAUTION: Gauge of electric supply wires must be of appropriate section, function of line current, as per local
electrical codes.
5.1 Power supply wiring
See the name plate for information on voltage and current.
Connect all wires to appropriate terminals as per the electrical diagram affixed inside the control panel door.
Correct connection tightening must be verified before start up, and after a short period of operation (typically after 2 weeks).
5.2 Typical electric diagram & legend
Thermal cut-out
automatic reset
or
Air flow switch
or EAS**
Single phase power supply
terminals
Thermal cut-out
Manual reset
Disconnect switch
3 phases power supply
terminals
Normally open
contact
Fuse
Ground terminal
Normally closed
contact
Heating element
Interlock
Contactor coil
Transformer
Control circuit supply
Back-up safety
contactor coil
Pneumatic electric
switch (ON/OFF)
Common
Pilot light
Pneumatic electric
controller
(modulating)
Solid State Relay input
terminal
Solid State Relay output
terminal
**Note: Electronic air flow sensor (EAS) is available/installed for heaters less than 50A and dimensions less than 48”x40”. Some
restriction may apply.
S
P
E
C
I
M
E
N
S
P
E
C
I
M
E
N
or
I
L
Electric Duct Heater
Specification and Installation Instructions
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5.3 Control signal selection and connection
5.3.1 Electric ON/OFF signal
Connect the contact demand wires to terminals com & 1, 2, 3, etc…of the electric heater.
Information about mechanical Air flow switch (PDN or PDA)
Upon application of 0.05’’w.c. (12Pa) minimum pressure, mechanical airflow switch will activate internal normally
open and normally closed contact.
Install pitot tube into the air duct up flow of electric heater.
Make sure that the arrow is in the direction of air flow.
5.3.2 Pneumatic ON/OFF signal
Connect a ؼ’’ (6mm) pneumatic signal tube onto pneumatic electric switch to activate each of the heating stages.
Information about Pneumatic electric switch
(PSO or PSC)
Upon application of demand pressure, pneumatic switch
will activate internal normally open (PSO) or normally
closed (PSC) contact.
Set point is adjustable from 2 to 20PSI (14 to 138kPa)
5.3.3 Electrical modulating signal, 0-10 or 2-10Vdc or 4-20mA
Connect the control signal demand wires to terminals & of the electric heater.
Information about Neptronic
®
electronic controller (HEC)
Neptronic® electronic controller (HEC) is a universal controller accepting any input signal used in the HVAC industry and
converting it to a modulating and/or ON/OFF control signal to solid state relay(s) and contactor(s).
If the electric heater is equipped with only one modulating stage, part number is HEC0000; and if the electric heater is equipped
with more than one stage, part number is HEC0002 or HEC0005.
Signal 2-10 Vdc
4-20mA Input
Signal 0-10 Vdc
Signal 0-10 Vdc by Neptronic
®
thermostat TRO5404
AIR FLOW
Pneumatic signal
inlet port
+
-
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
Jumper on
2-10 of J1
No Jumper
on J4
J1 J2
J2
Jumper on
VDC of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
+
-
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
Jumper on
2-10 of J1
No Jumper
on J4
J1 J2
J2
Jumper on
MA of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
+
-
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
Jumper on
0-10 of J1
No Jumper
on J4
J1 J2
J2
Jumper on
VDC of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
Common (-)
24 Vac (+)
External
Sensor
(optional)
12 3 4 5 6 7 8 9
TRO5404
HEC
INPUT
A17
COM
A16
ELECTRIC
HEATER
-
2
+
0-10 Vdc (+)
Electric Duct Heater
Specification and Installation Instructions
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5.3.4 Electric digital signal, AC or DC
Connect the control signal demand wires to terminals A16 & A19 for an AC signal or & for a DC signal.
Information about Neptronic
®
electronic controller (HEC)
If the electric heater is equipped with only one modulating stage, part number is HEC0000; and if the electric heater is equipped
with more than one stage, part number is HEC0002 or HEC0005.
AC Digital Input (Hot to 24 VAC)
The position on J1 and J2 will not matter. The signal on A19 will be priority.
AC Digital Input (Ground)
The position on J1 and J2 will not matter. The signal on A19 will be priority.
DC Pulse Input
Signal pulse by Neptronic
®
thermostat TRO5404
5.3.5 Electric Neptronic
®
signal, resistive
Connect the control signal demand wires to terminals A17 & A18 of the electric heater.
Internal set point option:
Temperature set point is adjustable directly on the electric heater, preventing over adjustment by user.
Part number of the electronic controller is HEC000P.
Internal set point & STC8-13 or STR1-13
Control range: 61ºF to 100ºF [16ºC to 38ºC]
Adjustment of the internal set point:
Adjust potentiometer INT SP at the desired temperature as
measured in the duct (if you use a STC8-13) or in the room
(if you use a STR1-13).
Note
: Internal set point option is available with the following
limitations:
1. Model open coils only.
2. 1 heating stage only of 10 kW maximum.
3. Dimension of W=48’’ (1.2m) and H=40’’(1m) maximum.
No internal set point
If the electric heater is equipped with only one modulating stage, part number of electronic controller is HEC0000; and if the
electric heater is equipped with more than one stage, part number is HEC0002 or HEC0005.
STS3-13
ITO3 & STC8-13 or STR1-13
RETURN
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
No Jumper
on J1
Jumper on
HIGH of J4
J1 J2
J2
No Jumper
on J2
0-10
2-10
VDC
MA
HOT
DIGITAL
INPUT
A16
A17
A18
A19
TPM
STS3
RETURN
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
No Jumper
on J1
Jumper on
LOW of J4
J1 J2
J2
No Jumper
on J2
INPUT
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
+
-
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
Jumper on
TPM of J1
No Jumper
on J4
J1 J2
J2
Jumper on
VDC of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
Common (-)
24 Vac (+)
External
Sensor
(optional)
12 3 4 56 7 8 9
TRO5404
DC pulse output (+)
HEC
INPUT
A17
COM
A16
ELECTRIC
HEATER
-
2
+
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
No Jumper
on J1
No Jumper
on J4
J1 J2
J2
Jumper
on STS3
of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
Internal Set Point
(only on model HEC0000P)
Jumper on
INT of J3
61
83
68 72 78
90
64
P
1
INT/
EXT
J
3
or
STC8-13
STR1-13
J3
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
No Jumper
on J1
No Jumper
on J4
J1 J2
J2
Jumper
on STS3
of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
STS3-13
or
STC8-13
ITO3
STR1-13
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
No Jumper
on J1
No Jumper
on J4
J1 J2
J2
Jumper on
STS3 of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
Electric Duct Heater
Specification and Installation Instructions
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5.3.6 Pneumatic modulating signal, 0-15 PSI
Connect the tube of the pneumatic signal to the port high pressure and leave the other port free.
Information about pneumatic electric controller (PCD or PCR)
Upon a pneumatic signal from 0-15 PSI (0 to 103kPa); and a minimum differential of 4 PSI (27kPa), pneumatic electric controller
will send a 0 to 10Vdc electric signal to HEC. Direct (PCD) or reverse (PCR) acting preset at factory.
Part number of the Neptronic® electronic controller when used with pneumatic electric controller is HEC1000.
Operation:
6 Operation condition
Air Flow :
Air flow must not be lower than the minimum air flow indicated on name plate.
Air flow going through the electric heater must be free of combustible particle, flammable vapour or gas.
Open Coil: Air flow going through the electric heater must be free of dust.
Zero clearance construction:
Neptronic electric heaters are designed and approved for zero clearance to combustible material. Insulation material may be
installed directly onto electric heater surfaces or onto air duct. However control panel must be accessible for maintenance.
Warning, Risk of fire and/or malfunction, Do not install insulation directly on heating elements.
7 Maintenance
Neptronic
®
electric heater does not require specific maintenance; however, we recommend a yearly inspection, typically before winter
season or after a long term shut down.
1) Visual inspection
Risk of electric shock. Disconnect all supplies before any visual inspection.
Verify good condition of heating element.
Heating element must be clean, free of dust or lint.
Open Coil: Verify carefully that there is no dust accumulation. Any dust of lint accumulation can lead to fire hazard.
Verify any indication of overheating condition (discoloration) as well as any trace of oxidation (rust).
2) Electrical inspection
Risk of electric shock. Disconnect all supplies before any electrical inspection.
Verify correct electrical connection tightening.
Verify the good condition of fuses (if any).
Verify resistance of each circuit against ground.
Verify correct operation of contactor(s).
If necessary, electrical component must be replaced only with identical original component.
STS3
INPUT
COM
AC IN
J1
LOW HIGH
J4
Jumper on
0-10 of J1
No Jumper
on J4
J1 J2
J2
Jumper on
VDC of J2
DIGITAL
INPUT
A16
A17
A18
A19
0-10
2-10
TPM
VDC
MA
STS3
24Vac
Pressure input (+)
Electric Duct Heater
Specification and Installation Instructions
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8 Quick Troubleshooting Guide
Risk of electric shock. Disconnect all supplies before any electrical inspection and troubleshooting.
Any service and troubleshooting must be done by a qualified electrician.
Symptom: Electric heater does not react to heating demand.
Troubleshooting steps
Note: these steps must be followed as presented, failure to do so will lead to improper and incorrect diagnostic.
1. Check that automatic and manual reset thermal cut-out is in closed
position.
2. Check for 24Vac (control voltage) at the secondary fuse.
If Electric ON/OFF signal
3. Check for air flow in air duct and for proper action of air flow switch (refer to section 5.3.1 of this manual). If the air flow
switch does not react (closing the normally open contact) to air flow, verify the air flow switch and pitot tube installation. If
the air flow switch still does not react to air flow after being verified, it indicates that it is defective and must be replaced.
If Electric modulating signal
3. Depending on the control signal (refer to the appropriate
section from 5.3.3 to 5.3.6 of the manual) verify that control
signal jumper(s) setting and connections are correct.
4. Check for control signal to the appropriate control signal
input terminal on the HEC Pcb. If control signal is not
present, check for control wirings between thermostat and
electric heater.
5. If the electric heater is equipped with the electronic air flow
sensor, disconnect the sensor Ts1 and Ts2 one at a time
and then both simultaneously. If the heater starts to
operate, search for a short in wiring or in the sensors
themselves. The sensors may have to be replaced.
6. Verify proper operation of HEC Pcb. When control demand
is at 50%, the TPM green LED (LD5) must blink
accordingly. If LED is not blinking, HEC Pcb is defective
and must be replaced.
7. Verify proper action of Solid state relay(s) (SSR). When
demand is at 0%, output voltage to SSR at the output
terminals on HEC Pcb must be between 0 to 0.2Vdc. When
demand is 100%, output voltage must be 25Vdc. If output
voltage to SSR does not correspond to these values, HEC
Pcb is defective and must be replaced.
8. If the electric heater is equipped with more than one
modulating heating stage (typically first stage is modulating
and supplemental stages are on/off), verify operation of
on/off relay(s). When heating demand is at 100%, 24Vac
must be present to corresponding contactor coil and the
contactor contact must close.
If control voltage (24Vac) is not present or contactor contact
is not closing, the HEC Pcb or wiring is defective.
9 Technical Support
For any questions or specific requests, please consult our website: www.neptronic.com
Or call: 1 800 361-2308, and ask for the Electric Heater Department.
or (514) 333-1433
Fax : (514) 333-3163
Check for 24Vac
at control fuse
Output terminals to heating
stages contactors
Step 7
Output terminals to SSR(s)
Step 5
Input terminals from electronic airflow
sensors
Step 3
Control signal selection jumpers
Step 6
TPM Green
LED
