Keltech C2N363/600D, C2N363/480D, C2N503/600D, C2N503/480D, C2N363/415D Installation Manual

C2N shown with optional leg kit

Installation

Keltech® C2N Series
Tankless Heater Models

C2N36, C2N50

Voltage options:
600V 3-phase
480V 3-phase
415V 3-phase
400V 3-phase
380V 3-phase

Table of Contents

Pre-Installation Information .........................2–3

Storage Instructions .................................3

Mounting Heater....................................4

Plumbing Installation ................................5

Electric Installation ..................................6

Start Up Check List .................................7

Start Up ..........................................8

Digital Controller Operation ...........................9

Operational Tests ...............................10–11

Product Options ...................................11

Maintenance......................................12

Troubleshooting ................................12–13

Special Installation & Operating Instructions ..........14–17

215-1821 Rev. B; ECN 16-17-005
© 2016 Bradley
Page 1 of 17 5/3/2016

Keltech Incorporated

A Subsidiary of Bradley

729 S. Grove St., Delton, MI 49046

[phone] 999 4320

Fax: [phone]
www.bradleycorp.com

C2N Series Tankless Heater Installation

DANGER

Tip over hazard. System can crush you resulting in serious injury or death. Read and follow precautions in this
installation manual that accompanied the heater for instructions on how to safely transport and anchor heater.
Do not transport with the heater in the vertical position. This heater is top heavy and should not be placed in
the vertical potition until the site is prepared to anchor the heater to the wall or the legs to the floor.

WARNING

Read this manual BEFORE using this equipment. Failure to read and follow all safety and user information
could result in death, serious personal injury, minor burns, property damage, or damage to the equipment.
Keep this Manual for future reference. Failure to comply with proper installation and maintenance instructions
could contribute to the heater’s failure.

A qualified plumber or electrician should install and service this system. Install system according to these
instructions and in compliance with national and local codes.

ASSE standard 1016, 1069 or 1070 listed devices should be used at fixtures to prevent possible injury. Severe
bodily injury including scalding, chilling, and/or death may result depending upon system water pressure
changes and/or supply water temperature changes.

For safe operation of the heater, observe all warning labels as indicated.

Water heater system under pressure. Do not open enclosure while in operation.

These heaters should never be used to provide “anti-scald” or “anti-chill” service.

Hazardous voltage inside enclosure may result in serious burns or death. Disconnect power supply before
performing any work in the enclosure.

Failure to ground this system may result in death or serious injury.

Make sure that all water supply lines have been flushed and then completely turned off before beginning
installation. Debris in supply lines can cause valves to malfunction.

CAUTION

Hot pipes! Do not touch. May cause minor burns.

NOTICE

These heaters do not provide protection from supply or outlet pipe freezing.

Consult local building and plumbing codes prior to installation. Should these codes differ from the information
in the Manual, follow the local codes. Inquire with governing authorities for additional local requirements.

Regular checking and cleaning of the heater’s internal components and check stops is necessary for maximum
life and proper product function. Periodic inspection and yearly maintenance by a licensed contractor is
required. Corrosive water conditions, and/or unauthorized adjustments or repairs could render the heater
ineffective for its intended service. Frequency of cleaning and inspection depends upon local water
conditions. For heaters with adjustable output temperatures, check and adjust as needed at initial installation
and on a quarterly basis.

IMPORTANT

Read this entire installation manual to ensure proper installation. When finished with the installation, file this
manual with the owner or maintenance department. Compliance and conformity to local codes and ordinances
is the responsibility of the installer. Product warranties may be found under “Products” on our Web site at
www.keltech-inc.com.

Separate parts from packaging and make sure all parts are accounted for before discarding any packaging
material. If any parts are missing, do not begin installation until you obtain the missing parts.

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Installation C2N Series Tankless Heater

Pre-Installation Information

General Information

The Keltech Tankless Water Heater provides instant and precise temperature-controlled hot water. To insure proper
performance, install the heater according to the following installation instructions and in compliance with applicable
national and local codes.

Keltech can supply heaters for most commercial and industrial hot water applications. Flow rates and temperature
figures are important for proper sizing. If needed to meet certain temperature demands, flow control devices are
readily available. See Temperature Rise Specifications Chart. Contact KELTECH, INC. for further information on
available flow control devices.

Operation and Setup

C2N Series heaters supply an unlimited amount of hot water with specific flow and temperature rise capabilities.
These heaters are energy efficient, reliable, and provide optimum performance in the most demanding applications.

Application Specific Requirements

The C2N Series can be used in many different applications that require custom tuning for specific applications to
maximize performance of the heater.

For use in a recirculation loop, the incoming loop temperature should not exceed 140°F (60°C).

For applications utilizing quick close valves or solenoid valves, it is important to install a hammer arrestor or surge
tank close to the point of use to absorb pressure spikes.

Installation Considerations

Maximum operating pressure: 150 psi (10 bar)
Standard flow activation: 0.75 gpm (2.8 lpm)

Certifications

Keltech Electric Tankless Water Heaters are certified by ETL to UL499, UL50E, CSA22.2 No 88 and NFPA 496
(for hazardous locations) and third party certified to NSF/ANSI 372. Heaters are compliant to NEC/NFPA 70 and
Canadian Electrical Code C22.1.

WARNING For safe operation of the heater, observe all the warning labels as indicated.

Storage Instructions

NOTICE! Keep Keltech Electric Tankless Water Heaters stored in original packaging until installation.

Recommended storage criteria:

Store Keltech Electric Tankless Water Heaters where temperatures exceed 35°F (2°C) at all times.

Indoor storage is recommended.

Minimize excessive on-site transport to reduce risk of shock and impact damage.

Alternate storage:

If in the original crate, Keltech Electric Tankless Water Heaters will withstand outside storage for approximately 1
month in most climates. Crate may not be capable of protecting the heater if left outside longer than this time frame.

If the Keltech Electric Tankless Water Heater is stored in an outdoor environment, care should be taken to protect the
heaters from:

• Rain or other falling precipitation via tarp or other waterproof media.

• Runoff and accumulation of groundwater from any source that may exceed 1 inch (25mm).

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C2N Series Tankless Heater Installation

Packaging

Crates are constructed from 3/4" (19mm) OSB.

Crate dimensions approx: 44" x 28" x 12" (1118mm x 711mm x 305mm)

Crates should not be stacked more than 2 high.

All crates must be stacked evenly and horizontally.

Safety issues related to packaging:

• Product should be transported with the care associated to packages labeled “FRAGILE” even if packaging is not
marked accordingly.

• Standard safety procedures for forklift transport and large items less than 1000lbs (454 kgs) should be followed at
all times.

• When stored, crate must be supported in entirety of its length and width.

1

Mounting Heater

WARNING HIGH VOLTAGE SHOCK. Disconnect power supply before performing any work inside

the heater enclosure.

Installation should be performed by a qualified plumber or electrician.

For best results, install heater as close as possible to the point of use.

Long pipe runs are not recommended. A heat loss of 1°F for every 10ft (3 meters) of uninsulated
pipe can occur.

When determining a mounting location, give consideration to the location of the main electrical panel
and ensure accessibility of the cabinet enclosure door and other plumbing for service/maintenance. 36"
(914mm) minimum in front of the cabinet enclosure is required.

Set heater in a vertical, upright position

A

with the water outlet located at top.

Standard Wall Mount

Mount heater to the wall using the (4)
mounting brackets on the back of the
enclosure. Bolt the heater to the vertical
surface. Vertical surface must support
150 lbs or more.

B

Optional Leg Kit

Use the floor mounting template on the
side of the crate to help with alignment.
Secure heater by bolting each leg to the
floor using 3/8" (10mm) anchor bolts.

Install the pressure and temperature relief
valve on hot water outlet immediately

C

following the union.

NOTICE! Valve must empty into a drain.

4"

(102mm)

8"

(203mm)

24"

(609mm)

16¼"

(413mm)

10¼"

(260mm)

4"

(102mm)

⁷⁄₁₆" x ¾"

(10mm x 20mm)

Slot

(6 Places)

Rectangle outlines on template are not
actual size of heater.

Template may require cutting to fit into
tight areas.
Holes are for alignment purposes and may
not represent actual drill size for mounting
hardware.

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Installation C2N Series Tankless Heater

2

Plumbing Installation

Components Needed:

• (2) Union 3/4"

• Shutoff Valve

• Pressure and Temperature Relief Valve (150 psi/10 bar)

• Y-Strainer (100 mesh) or Inline Filter (150 microns)

• (2) Gate or Ball Type Valves

• Drain pipe

• Water hammer arrestor (recommended)

• Elbows, nipples and fittings as needed

CAUTION To avoid damage to the electronics

or internal wiring, do not perform any
brazing or sweat soldering inside the
enclosure.

NOTICE! Failure to install proper filtration may

result in a flow switch malfunction.

NOTICE! To avoid water damage, install a drain

pipe from the pressure relief valve to
an unrestricted drain.

If end use fixture is not at the highest point in
the plumbing loop, then an automatic air vent
valve must be added at the highest point in the
system or at any drop to eliminate trapped air.

Install shutoff valve above (upstream of) the heater.

A

inlet

Install one union on the water inlet side of the
heater. Install one 100 Mesh (150 micron) Y-strainer
above (upstream of) union.

Install one union on the water outlet side of the heater.
Install one P & T Relief Valve above (downstream of)
union.

Install the pressure relief valve (150 psi/10 bar) and

B

outlet plumbing of heater per code requirements and
route relief valve discharge to drain. Make sure no
shutoff valve is between the water heater outlet and
the relief valve, as well as no shutoff valve between
the relief valve discharge and drain. Install hammer
arrestor. Ensure plumbing is secure and not subject
to vibrations.

Use 3/4" hard copper tubing or pipe as needed.

C

Dim. "A" Dim. "B"

31-1/2" (800) 30" (762)

37-1/2" (953) 36" (914)

Outlet

36kW

50kW

Inlet

Dimensions, Plumbing and
Electrical Configurations

3/4"

Female

NPT Outlet

2"

(51)

A

B

10"

(254)

22-1/2" (572)

24" (610)

3/4" Female

NPT Inlet

Optional Fused

Disconnect

Suggested

Location for

Power Entrance

- Provided By
Installer

8"

(203)

8-3/4"

(222)

P&T Relief

Valve

3-3/8"

(86)

To Drain

Ball Valves

TEMPERATURE CONTROLLER

R

1

LOAD L

2

3
4

5

LOAD R

GROUND FAULT

READY

TESTFAULT RESET

Suggested Installation Configuration

Components provided by installer unless

otherwise specified. Reference the product

options sections or contact your local

Bradley Representative for product options.

Y-Strainer

Recommended

Threaded

Unions

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C2N Series Tankless Heater Installation

3

Electric Installation

WARNING Install product to rated line voltage in accordance to current local and national codes and

regulations.

WARNING All Keltech heaters must be fused in accordance with National Electric Code (NEC) for the

full load amperage listed on the nameplate rating for each heater.

WARNING Failure to properly ground the unit(s) per the National Electric Code could result in injury

or death.

Open enclosure door.

A

ELECTRICAL SPECIFICATIONS FOR HEATER (3 Phase)

NOTICE! Any option that requires field wiring

must be done with 600V cable per the
schematic that was shipped with the
heater.

NOTICE! Use a 4-core cable or multi-stranded

machine tool wire from an approved
isolating 3-pole switch or circuit
breaker.

NOTICE! Make sure the electrical cable is the

correct size to carry 100% of the full
load current. See table for proper
wire sizes.

Using a hole punch, cut a hole the proper
size for conduit connection; large enough
for the wire size for each heater. The

B

connectors need to be rated NEMA4/4X
to ensure proper sealing of the enclosure.

Model Voltage Amps kWatts

C2N363/600D 600 35 36 6 AWG*

C2N503/600D 600 49 50 4 AWG*

C2N363/480D 480 43 36 6 AWG*

C2N503/480D 480 60 50 3 AWG*

C2N363/415D 415 38 27 6 AWG*

C2N503/415D 415 52 37 4 AWG*

C2N363/400D 400 36 25 6 AWG*

C2N503/400D 400 50 35 4 AWG*

C2N363/380D 380 33 23 8 AWG*

C2N503/380D 380 47 31 4 AWG*

* Based on the NEC Table 310.15 for 75°C insulated copper wire @ 30°C
Ambient. Aluminum wire requires larger gauges.

Not all available (optional) voltages are listed in table.

Min Wire

Size

Run wires through the appropriate size

C

conduit.

Connect wires to the system terminal
block or fused disconnect inside the

D

enclosure.

Connect the ground wire to the stud

E

provided with the “Ground” label beneath it.

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4

Start Up Check List

Plumbing

 System is set in a vertical, level, and upright position with the outlet located at the top. System is mounted to the

wall using the (4) mounting brackets on the back of the enclosure or bolted to the floor with the optional leg kit.

 Confirm installation of shutoff valve above (upstream of) the union on the inlet connection. Confirm installation of

a Y-strainer (100 mesh screen) or inline filter (150 micron) between the inlet shutoff valve and the heater.

 Pressure and temperature relief valve is installed on tepid water outlet immediately following the union. No valve

or restriction is between the relief valve and the system or the relief valve and drain. Shutoff valve is installed
after pressure and temperature relief valve on outlet if required by local or national plumbing codes.

 If the hot water process is not at the highest point in the plumbing loop, then an automatic air vent valve must be

added at the highest point in the system plumbing loop to eliminate trapped air.

Electrical

 Verify supply voltage matches the indicated voltage on the Serial Tag. Serial Tag is located within the heater

enclosure on the upper left corner of the back plate (mounting plate).

 Appropriate conduit is installed properly, secured and sealed to unit enclosure per NEC and hazard

location requirements.

 Appropriate conductors for unit routed through conduit and secured to power block inside the enclosure. All

electrical is installed in accordance with national and local electrical codes, including fuse size and rating.

 Appropriate earth ground is installed to the lug provided on enclosure backplate.

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C2N Series Tankless Heater Installation

5

Start Up

WARNING Make sure the circuit breaker for the heater is OFF.

Be sure that plumbing and electrical are complete per Start Up Check List.

Slowly turn on water supply to the unit
with the enclosure door open and the

A

circuit breaker in the off position.

Slowly turn on the water outlet valve,
activate the connected process requiring
heated water (faucet, shower, etc.), then
flush the system for 5 minutes to ensure all
air is purged from the system.

B

NOTICE! Failure to bleed air properly

will damage elements and
cause heater malfunction.

Turn off the connected process and
check the entire system to verify leak-free

C

installation.

Energize the electrical service to the unit

F

by switching on the circuit breaker.

Unit is now in the ready state.

G

Turn on the connected process; observe
output temperature rise to setpoint.

NOTE: Top portion of temperature

H

controller displays output temperature,
bottom displays setpoint temperature.

When startup is complete, leave circuit
breaker in the ON position. The Green

I

power light should be illuminated.

Close enclosure door and secure.

D

If your heater has the EXP2 option and
is located in a Class I Division 2 area,
please review Special Instructions &
Operation Instructions section for all
proper electrical connections and sealing
to ensure the installation will provide the

E

proper protection. Proceed to Step F once

you have completed the steps in the Spercial
Instructions & Operation Instructions or if you
do not have this option.

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Installation C2N Series Tankless Heater

6

Digital Controller Operation

The preprogrammed digital controller is mounted through the bezel on the enclosure door. The digital
controller will be powered but the bottom display will read OFF until water is flowing through the heater.
The bottom display will then display the setpoint temperature (See Digital Controller Operation section for
more information).

Refer to table and drawings below for instructions to change the desired set
point temperature of the controller.

Description Upper Display Lower Display Function

EZ Key Toggles output on/off

Setpoint Up Button Increases output temperature

Setpoint Down Button Decreases output temperature

Infinity Key Back to Home page

Advance Key Advances through parameter prompts

Auto, Man, Off C.r71 Turns Control Loop On/Manual/Off

XX.X% h.Pr1 Heater Power %

no AUt1 Autotune (Contact Factory)

C or F C_F1 Change Temperature Units from F to C

Output Indicators (1-5) Output 1,2,3,4 or 5 are active and operating if

these LEDs are illuminated.

Setpoint Temperature
(Lower Display)

Output Temperature
(Upper Display)

Displays:

Displays:

• Setpoint

• Percent Power

• Temperature units F or C

• Menu prompt name

• Alarm code

• Actual process temp. of outgoing water

• Prompt parameter value

• Error code (feature disabled)

Layout Diagram ON - Heating OFF - No Flow

Output Indicators

1

2

Output Temp.

3
4

Setpoint Temp.

5

1

Output

2

Temp.

3
4

Setpoint

5

Temp.

1

2

3
4

No Flow

5

Output
Temp.

Setpoint Up

EZ Key

Setpoint Down

Advance KeyInfinity Key

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C2N Series Tankless Heater Installation

7

Perform Operational Test No. 1

Ensure the enclosure door is closed
prior to performing operation test.

Set the 3-pole switch or circuit breaker to the

A

ON position.

Start the water flow through the heater by
starting the process or fixture this heater is

B

connected to in order to activate heater.

When flow rate reaches approximately

0.75gpm/2.8 lpm (standard), the flow switch
activates and begins the heating process.

When the flow switch activates:

• Phase indicator lights illuminate on the front

C

bezel verifying power supply connection to the
heating elements via the solid-state relays.

• Element load lights may be solid or flash
in unison as heating elements modulate
depending on the hot water demand.

• Lower display on controller goes from off
to setpoint temperature.

Press the up or down arrow keys to
adjust the set temperature. The controller

D

displays the temperature of water
measured at the outlet.

Located on the panel are two 36kW-50kW
green ready lights. When illuminated, the
safety circuit is engaged and ready for use.

Test water temperature and stability at
outlet by viewing the display. Controller

E

displays (in red) the temperature of water
exiting the heater.

Heater will not energize heating elements if the
inlet water temperature is equal to or greater than
the temperature set on the digital controller .

8

Perform Operational Test No. 2

Each model has precise specifications for temperature rise capabilities.

Turn on hot water faucet/fixture/process. The

A

heater should activate immediately.

If the water flow exceeds maximum heating capacity of the heater, the temperature of water at the outlet
may be lower than the temperature selected on the controller. See table below to determine maximum
temperature rise capabilities.

Temperature Rise (GPM & F°)

Models 480/600V kW

C2N36 36 122 82 62 50 40 34 30 26 24 22 20

C2N50 50 170 113 85 68 57 48 43 38 34 31 8

Models 480/600V kW

C2N36 36 50 46 34 28 22 19 17 14 13 12 11

C2N50 50 94 63 47 38 32 27 24 21 19 17 16

1 gpm

ΔT °F

3.8 lpm
ΔT °C

2 gpm

ΔT °F

7.6 lpm
ΔT °C

3 gpm

ΔT °F

11.4 lpm
ΔT °C

4 gpm

ΔT °F

Temperature Rise (lpm & C°)

15.1 lpm
ΔT °C

5 gpm

ΔT °F

18.9 lpm
ΔT °C

Turn off hot water faucet/fixture/process.
The flow switch will deactivate and shut

B

off power to the heater.

6 gpm

ΔT °F

22.7 lpm
ΔT °C

7 gpm
ΔT °F

*May exceed the maximum temperature setting of the heater

26.5 lpm
ΔT °C

8 gpm

ΔT °F

30.2 lpm
ΔT °C

9 gpm

ΔT °F

34.1 lpm
ΔT °C

10 gpm

ΔT °F

37.8 lpm
ΔT °C

11 gpm

ΔT °F

41.6 lpm
ΔT °C

12 gpm

ΔT °F

45.4 lpm
ΔT °C

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Installation C2N Series Tankless Heater

Output heating capacity is reduced if these heaters are installed on 415V, 400V or 380V 3-ph.
Contact the factory to supply this information.

Satisfactory performance of the heater is dependent upon a specific flow rate vs temperature rise capability. If the
desired temperature is not achieved, please verify the following:

1. Circuit breaker is on and rated for the maximum power draw.

2. Heater is drawing the proper current for the supply voltage on all 3 phases.

3. All 3 phase indicator lights are lit (not flashing) indicating maximum power draw and maximum
amperage is being drawn.

4. Flow rate and temperature rise in the water heating process are compatible with the heater specifications.

5. Verify there is no additional supply of cold water entering the line downstream of the heater.

Product Options

GF (Ground Fault): Detects electrical leakage from external sources to protect equipment, electronics, and the heat

exchanger from being damaged in the event of a power fault. After turning on water, then power, test ground fault:

1. Press GF Test button.

2. Watch for ground fault light to illuminate and Bank Ready light(s) to shut off. The Ground Fault system is active
and in working order.

3. Press the GF Reset button, hold for 2 seconds and release to reset ground fault.

If a trip occurs under normal operation DO NOT RESET Ground Fault without evaluation and
service.

Normal state is Ground Fault light OFF, Bank Ready lights ON.

FDS Fused Disconnect: Internal fused disconnect interlocks with enclosure door when energized, prohibiting access
to a live cabinet. Select the FDS option for an additional level of safety and convenience at the heater location.

T190 High Temperature Option: Reach and maintain temperatures as high as 190°F (88°C).

D1 Control Interface: Provides 4–20ma communication interface with temperature controller.

TE & TE2 Corrosive Fluid Protection: The TE option is a PFA Teflon® coated heat exchanger with bright annealed

stainless steel elements,FDA Approved (use for deionized water or mild corrosive fluid applications). Similar to TE,
the TE2 option is a single layer of Xylan Fluoropolymeric coated heat exchanger with bright annealed stainless steel
elements, FDA Approved for Food Contact (use in deionized water applications).

EXP2 (Explosion Proof Purge System): Keltech's EXP2 option makes heaters compliant for classified areas;
Class I Division 2, Groups A, B, C, D, Temp Code: T5. The Purge System requires a supply of clean instrument air or
inert gas (provided by installer). This supply maintains a positive internal pressure and prevents the enclosure from
filling with flammable gases, dusts or vapors from the ambient environment. Complete installation provided in this
manual.

Low Flow (L5): 0.50 GPM (1.9 lpm) option for heating water when lower flow rates are required.

N4X (NEMA 4X Enclosure): Corrosion resistant enclosure made of stainless steel and ideal for harsh environments.

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C2N Series Tankless Heater Installation

Maintenance

Preventative maintenance is important for optimal performance of the heater. To ensure the heater works properly,
always keep the inside of the enclosure dry. Moisture inside an enclosure increases the humidity, which condenses
on cooler surfaces. This can cause electrical problems and reduce the efficiency of enclosure insulation. To prevent
problems perform the following:

• Verify the interior of the enclosure is dry.

• Verify there are no leaks in seals of enclosure and that in high humidity environments all enclosure egresses are
properly sealed.

• Ensure plugs are in place on back side of enclosure.

• Check seals monthly during temperatures above 32°F (0°C) and weekly during temperatures below 32°F(0°C).

• Bimetal Manual Reset Safeties are set to trip at 175°F (79°C). If this temperature is reached, the Bimetal Manual
Safeties will trip and need to be reset.

• All heaters require filtration of 150 microns or smaller to ensure proper operation. Y-strainers or additional filtration
should be verified and cleaned at least every 6 months or more often in areas where hard water sediment is
present in the water.

To clean the Y-Strainer:

1. Turn the power off at the circuit breaker panel.

2. Shut off the installer supplied cold water isolation valve to the heater.

3. Relieve pressure in the plumbing lines.

4. Position a bucket under the cold water inlet to catch any water that may still be in the pipe.

5. Loosen the plumbing connection on the Y-strainer to get to the screen.

6. Remove screen and clean out debris. Use a wire brush to clean smaller particles from the screen.

7. Once the screen is clean, put it back into the Y-strainer housing and secure the plumbing connection.

8. Before switching the power back on, bleed the air out of the lines by turning heater water supply back on and

the plumbing fixture or process farthest from the heater.

9. With the air purged, turn on all circuit breakers supplying the water heater.

• At the same time the Y-strainer or additional filtration is cleaned, it is a good practice to also check all valves
connected to the system. With no water flow through the heater, work both the inlet ball valves and the outlet gate
valves open and shut to break up any calcium deposits that may have formed from the valve being open for an
extended period of time. Power to the heater does not need to be turned off to do this.

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Troubleshooting for Controller

Problem Solution

No Power Verify power is on.

Check incoming service connection. Voltage must match
name plate rated voltage. Labels are located on upper left
of back plate (serial number label).

Turn power off. Check continuity of all internal fuses in
control transformer, heating elements or optional fused
disconnect circuits.

Check all field service circuit breakers or fuses.

Check the safety interlock door switch to make sure
that lack of power is not due to misadjustment or open
enclosure door.

Check system temperature limit control to make sure
it has not activated due to excessive heat exchanger
temperature or faulty sensor.

Turn power off. Check for loose or disconnected wires.

Basic Troubleshooting

Problem Solution

The heater does not work or works intermittently. 1. Heater is wired with the proper breaker and wire size.

Refer to Electrical Specifications table in Step 3 for
proper requirements.

2. Unit is receiving voltage from all 3 phases of the
power source. A load voltage reading is also helpful.

3. Verify the functionality of the flow switch.

4. At the wires from the flow switch, read "Open" without
flow and "Closed" with flow.

5. Water flow through the heater is adequate to activate
the flow switch at 0.75gpm/2.8 lpm (standard).

Turn power OFF before recording any Ohm readings.

If the above steps do not solve the problem, some additional checks may be performed. Follow the
schematic to perform the following continuity checks:

 High temperature bimetals (Manual Reset Safeties).

 Optional ground fault breaker must be in the closed position for the unit to work.

 All internal breakers must be in the ON position for the unit to work.

For additional information on Troubleshooting or other information, please call Keltech Inc. technical support at
1-800-999-4320. Please have Model No. and Serial No. available when seeking technical assistance. Serial No.
tag is located in the enclosure on the upper left hand corner of the back plate. Please record and maintain this

information at all times:

C2N Model No.

Serial No.

Bradley • 215-1821 Rev. B; ECN 16-17-005 5/3/2016

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C2N Series Tankless Heater Installation

Special Installation and Operating Instructions

Tankless Water Heaters With Optional Class I Division 2 Purge EXP2 Option

General Information

All Keltech Tankless Water Heaters with a model number suffix of – EXP2 have been fitted with a Z purge system to
pressurize the enclosure suitable for use in Class I Division 2 Hazardous Locations.

A Continuous Flow (Model CF) Mini-Z Pressurizing System has been fitted to the bottom of the enclosure.

Suggested region for power

1

Purge System

1

2

3

4

5

supplied by others

2

4

5

1

5"

(127mm)

18" (458mm)Max

Relief Valve

Conduit Hub

Class 1 Div. 2

Explosion proof

sealing fitting

supplied by others

entrance at left/bottom of enclosure.
Entrance hole and components to
be provided by installer.

2

Purge Control Panel
Class 1 Division 2

All installation egress from

3

panel must be sealed (electrical
conduit) for proper explosion proof
installation.

Spark arrestor with calibration orifice

4

is located behind the purge control
unit and through the bottom of the
enclosure.

Purge gas/compressed air inlet

5

fitting here.

EXP2 Installation Notes

1. Any tubing, conduit or fittings connected to the Pressurized Enclosure (PE) must conform to local codes for
flammability ratings.

2. All egress into PE must be plugged and properly sealed to minimize leakage of purge air. Use hazardous
location sealing fittings suitable for Class I locations within 18" (458mm) of enclosure.

3. The EXP2 purge system option is a continuous flow purge system and is calibrated to flow at 0.9 SCFM
(1.5291 CMH). To minimize waste, plug and seal all openings and conduit.

4. The system is designed for use primarily with compressed air. The source of the compressed air must be
from a non-classified area (see Purge Gas Supply Notes). Purge air must be clean, dry and free of flammable
gases. When inert compressed gases are used (Nitrogen, for example) the installer and facility manager must
take suitable precautions on-site so that buildup of the inert gas does not present a health hazard. Where risk
of asphyxiation exists, a warning label must be fitted to the Pressurized Enclosure (PE).

5. Adjustment of Purge System is not necessary. System is fully calibrated.

6. Connect to Purge System where indicated. Connection port is 1/4" NPT female. Supply pressure must be
regulated to 60–115 PSI (4-8 bar).

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5/3/2016 Bradley • 215-1821 Rev. B; ECN 16-17-005

Installation C2N Series Tankless Heater

Purge Gas Supply Notes

An alarm shall be provided to indicate failure of the protective gas supply to maintain the required pressure. Piping for
the protective gas shall be protected against mechanical damage.

Where the compressor intake line passes through a classified location, it shall be constructed of noncombustible
material, designed to prevent leakage of flammable gases, vapors, or dusts into the protective gas, and protected
against mechanical damage and corrosion.

The electrical power for the protective gas supply (blower, compressor, etc.) shall be supplied either from a separate
power source or from the protected enclosure power supply prior to any service disconnects of the protected
enclosure. Any protected enclosure that can be isolated from the protective gas supply shall be equipped with an
alarm. Where an alarm is used to indicate the loss of pressure in the cabinet:

• The alarm shall be located at a constantly attended location.

• The alarm actuator shall take its signal from the protected enclosure and shall not be installed between the

enclosure and the protective gas supply.

• The alarm actuator shall be mechanical, pneumatic, or electrical.

• Electrical alarms and electrical alarm actuators shall be approved for the location in which they are installed.

• No valves shall be permitted between the alarm actuator and the enclosure.

Intrinsically Safe (IS) Installation

Hazardous Location
Class I , Division 2
Groups A, B, C, D
T5 Hazardous (classified) Areas

Simple apparatus
device

MiniPurge: Option Code /IS
Vmax = 30v
Imax = 350mA
Ci = 0 Li = 0

1. Electrical equipment connected to associated apparatus should not use or generate more than 250 volts.

2. Installation shall be in accordance with the manufacturer's instructions and the National Electrical Code
(NFPA 70)

3. For guidance on Installation see ANSI/ISA RP12.6 (Installation of IS Instrument System in Class I
Hazardous Locations).

4. Voc or Vt of associated apparatus is less than Vmax
Isc or IT of associated apparatus is less than Imax
Ci plus capacitance of interconnecting cabling is less than Ca of the associated apparatus
Li plus inductance of interconnecting cabling is less than La fo the associated apparatus

5. "Simple Apparatus" is a device that will not generate or store more than 1.2V, 0,1A, 25mW or 20uJ

Non- Hazardous Location
(or suitably protected enclosure)

Intrinsically Safe
Interface Unit

Power Supply

Outputs to relays or
power contactors

Bradley • 215-1821 Rev. B; ECN 16-17-005 5/3/2016

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C2N Series Tankless Heater Installation

IS Installation continued…

All quarter turn latches in the door of the PE must be fully latched for proper operation. Power to the PE must be
turned off before opening the enclosure.

WARNING This Pressurized Enclosure shall not be opened unless the area is known to be free of

flammable materials or unless all devices within have been de-energized.

Power shall not be restored after the enclosure has been opened until the enclosure has been purged for allotted
time (see table below). Time begins when pressure indicator turns green after the door of the enclosure has been
closed and fully latched.

WARNING Ignition of potentially explosive gas/air mixtures may result if power is turned on before the

allotted purge time!

Expo Technologies CF systems have a Minimum Pressure Sensor set to a pressure of at lease 0.1" WC (0.25bar). When
the PE pressure is above this set point the sensor produces a positive Pressurized signal. This is displayed on the Red/
Green indicator located on the Purge System. This signal can be used to operate an electrical contact for a remote Alarm.
This signal may be supplied to the pressure operated switch suitable for Intrinsically Safe circuit in accordance. When the
enclosure pressure falls below the set point of the sensor, the Pressurized signal is removed, and the Alarm conditions
occurs. This Alarm must be located where it can be readily observed according to NFPA496 requirements. No valves may

be fitted between the Expo Technologies system and the alarm switch.

WARNING Never turn on the power without purging first, unless you have proved the interior of the PE is gas

free and checked that the “Pressurized” indicator is green!

Commissioning Test

Commissioning Continuous Flow Keltech Option EXP2 System:

1. Open the air or gas supply shutoff valve.

2. Adjust the Flow Control Valve (FCV) so that the enclosure pressure rises to the point where the "Pressurized"
indicator turns green.

3. Lower the PE pressure until the Pressurized indicator turns Red.

4. Open the FCV again and set the PE pressure to a level somewhere between the minimum pressure sensor
set point and the RLV opening pressures. This working pressure is not critical. Enough pressure to keep
the“Pressurized” indicator Green is sufficient.

5. On EXP2 Purge System the timing function if performed by the user. The user must ensure that the time delay
between the indicator turning Yellow and the application of power to the PE is not less than the minimum time
required to purge the PE as shown in the table below.

Normal Operation: Turn the air supply valve ON to start or OFF to stop the system. The user must close the Power
Switch only after the enclosure has been pressurized and purged sufficiently to ensure that the interior of the enclosure
is gas free. It is the operator’s responsibility to shut off the power as soon as possible after a pressure failure.

PURGE TIME CHART - EXP2 Option

for use with EXPO Mini Z Purge 1ZCF/bp/IS

Model/Enclosure

Group Size

C2N36 3.33 (0.09) 13.32 0.9 #2 15

C2N50 4.00 (0.11) 16.00 0.9 #2 18

Cubic Feet

(Cubic Meters)

Volume

Exchanges

X 4

Orifice

Size

Orifice

No.

Purge

Time

(Minutes)

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5/3/2016 Bradley • 215-1821 Rev. B; ECN 16-17-005

Installation C2N Series Tankless Heater

Special Installation Maintenance

Routine Maintenance of the System (Every 6 months)

Recommended maintenance of the systems is as follows:

Repeat Commissioning test at least every six months. The test includes checking the opening pressure of the Relief
Valve, setting of the Minimum Pressure Sensor, the “Normal Working Pressure” of the enclosure. Test that the interlock
and alarms function correctly.

Check the Relief Valve and any other Spark Arrestors. Remove any debris or corrosion, or replace the Spark Arrestor.

Check the condition of the air supply filter element. Clean or replace it as necessary.

Periodic Maintenance (Every 18-24 months)

At least every two years, the following additional checks are recommended:

Apparatus (Heater, Purge Systems, Alarms etc.) is suitable for the Hazardous Location.

There are not unauthorized modifications.

The source of air is uncontaminated.

The interlock and alarms function correctly.

Approval labels are legible and undamaged.

Adequate spare parts are carried.

The action of pressure failure is correct.

Bradley • 215-1821 Rev. B; ECN 16-17-005 5/3/2016

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