Chromalox NWH Installation guide

Brand: Chromalox

Model: NWH

Type: Installation guide

Chromalox

DIVISION

SECTION

NWH

SALES

REFERENCE

DATE

SERVICE REFERENCE

Installation Instructions

and

RENEWAL PARTS IDENTIFICATION

PE407-10

161-048468-001

NOVEMBER, 2002

(Supersedes PE407-9)

GENERAL

INSTALLATION

Type NWH-6 Circulation Heater

(for Water Heating)

FIRE/EXPLOSION HAZARD. This heater is not

intended for use in hazardous atmospheres where

flammable vapors, gases, liquids or other com-

bustible atmospheres are present as defined in the

National Electrical Code. Failure to comply can

result in personal injury or property damage.

The NWH-6 series is a general-purpose water or water-based solution

circulation heater intended for use indoors. It is designed for 150 psig

at 350˚F per ANSI standards, -20˚F minimum.

The 6 copper-sheathed tubular elements are centered in a 5” diam-

eter galvanized steel heating chamber and sealed into a removable

steel flange. The assembly is surrounded by 1-1/2” insulation and

sheet metal jacket.

Depending upon the order specifications, the NWH-6 may or may

not be factory equipped with an AR-215A or other Chromalox ther-

mostat. Such thermostats function to control outlet temperatures and to

limit internal temperatures under abnormal flow conditions. These

controls do not fail safe.

The system designer is responsible for the safety

of this equipment and should install adequate

back-up controls and safety devices with their

electric heating equipment. Where the conse-

quences of failure could result in personal injury or

property damage, back-up controls are essential.

ELECTRIC SHOCK HAZARD. Disconnect all power

before installing or servicing heater. Failure to do so

could result in personal injury or property damage.

Heater must be installed by a qualified person in accor-

dance with the National Electrical Code, NFPA 70.

1. Vertical Mounting (Preferred) —

When the heater is vertically mounted, the terminal enclosure will

be at the top of the heater. The water inlet pipe will be located on

the side near the bottom of the heater and the outlet pipe at the top.

The axis of the chamber will be in a vertical position as in the

photo above and as in Figure A.

Note: A drain pipe located at the bottom of the heater should be

provided and enough room left, when mounting heater, to allow

draining the heater.

2. Horizontal Mounting (Optional) —

When mounting heater horizontally, inlet and outlet pipes must be

up. In any other position, heater cannot be purged of air, and ele-

ments may be seriously damaged. (See Figure B.)

Specifications — Table A

Incorrect

Correct

Figure A

Vertical Mounting

Correct

Incorrect

Dimensions (In.)

Watt

Model Volts Phase kW

Density

A B C

NWH-62415 1 or 3 24 45.8 41-3/4 30 11-3/8

NWH-63015 1 or 3 30 45.8 48-3/4 37 14-7/8

NWH-64015 3 40 45.8 60-1/4 48-1/2 20-5/8

NWH-65015 3 50 45.8 73-5/8 61-7/8 27-5/16

NWH-66015 3 60 45.8 86-5/8 74-7/8 33-7/8

240

480

25”

8-5/8”

16-1/16”

Thermostat

Type AR

Mounting Lugs

3/8” - 16

Threaded Holes -

1-1/2” Deep

1-1/4” Centers

2” Pipe Inlet

2” Pipe Outlet

1-3/8” Conduit

Openings

Figure B

Horizontal Mounting

WIRING

ELECTRIC SHOCK HAZARD. Any installation involv-

ing electric heaters must be performed by a quali-

fied person and must be effectively grounded in

accordance with the National Electrical Code to

eliminate shock hazard.

1. Be sure line voltage matches heater voltage (on nameplate).

2. All wiring should be done in accordance with local codes and the

National Electrical Code by a qualified person as defined in the

NEC.

3. Power controllers must be used when heaters are rated 3 phase and

when the heater amperage exceeds the rating of the thermostat.

4. Refer to Wiring Diagrams, Table B, to properly connect the

heater.

Wiring Diagrams - Table B

INSTALLATION

3. Whether vertically or horizontally, the heater should be rigidly

mounted so that vibration is at a minimum since excessive vibration

will result in erratic thermostat operation. The NWH-6 is provided

with mounting lugs to support the heating chamber. (See photo.)

By using a slotted mounting assembly on either of the lugs, the heater

chamber will be permitted to expand with increasing temperature.

5. Provide adequate space at terminal end to permit withdrawal of the

heater from chamber should servicing be required.

FREEZE HAZARD. This unit is equipped with a ther-

mowell for process control or over-temperature con-

trol. Do not allow moisture to accumulate in ther-

mowell. Freezing temperatures can cause damage

that may result in the heated medium leaking into ter-

minal enclosure.

To prevent moisture accumulation in cryogenic applications or

when heater is exposed to freezing temperatures:

A. Slope conduit away from housing (drip loop).

B. Seal all conduit openings to moisture/explosion resistant ter-

minal enclosure.

C. Insulate terminal enclosure.

D. Fill thermowell(s) with silicone fluid when heater is mounted

with terminal enclosure up.

FIRE HAZARD. Since heaters are capable of develop-

ing high temperatures, extreme care should be taken

to:

A. Provide 6 inch minimum spacing from chamber and related

piping to combustible materials.

B. Do not operate heater in or near combustible fluids, vapors,

gases or dust-laden atmospheres as defined by the National

Electrical Code.

Model

240V, 480V, 480V, 480V,

2-3Ø Fig. 2-1Ø Fig. 3Ø Fig. 2-3Ø Fig.

NWH-62415 1 2 3 —

NWH-63015 1 2 3 —

NWH-64015 1 — — 4

NWH-65015 — — — 4

NWH-66015 — — — 4

Contactor

Thermostat

1L1

1L2

1L3

2L1

2L2

2L3

120V

240V

NOTE: Dotted lines indicate “customer furnished.” However, Thermostat could have been furnished by Chromalox if so specified on the order.

Contactor

Thermostat

120V

240V

Line

Figure 1 - NWH-6

240V, 2-3Ø ss

Figure 2 - NWH-6

480V, 2-1Ø

OPERATION

IMPORTANT: Type NWH Circulation Heaters are

equipped with copper heating elements and galva-

nized-steel heating chambers. It is the responsibil-

ity of the purchaser of the heater to know the

chemical composition of the corrosive solution and

the character of the materials entering the solution

as well as the corrosive effect of the solution upon

the heating elements and chamber.

Sheath corrosion can result in a ground fault

which, depending upon the solution being heated,

can cause an explosion or fire.

1. Do not heat solutions that are corrosive to the heating element

sheath or the heating chamber.

2. Terminal ends of heater must be protected from drippings, con-

densation, spray or direct spill-over of material. Their presence at

the terminals may damage heater electrical insulation. Liquid-tight

terminal enclosures are available to protect heater. Consult your

Local Chromalox Sales office.

3. If foreign material is carried by the liquid flow, install suitable fil-

ters in the inlet pipe line to the heater.

4. Do not allow heater to operate when liquid flow is interrupted.

FIRE/EXPLOSION HAZARD. Do not exceed the

Pressure-Temperature rating of the flange as listed in

ANSI B16.5.

MAINTENANCE

ELECTRIC SHOCK HAZARD. Disconnect all power

before installing or servicing heater. Failure to do

so could result in personal injury or property dam-

age. Heater must be installed by a qualified person

in accordance with the National Electrical Code,

NFPA 70.

1. Remove heating element assembly periodically to check heater

sheath for scaling, corrosion or excessive oxidation. Correct oper-

ating conditions to minimize sheath deterioration. Note:

Maintenance intervals to be determined by the user based on their

knowledge of the heated medium and operating conditions.

2. Periodically check temperature control and limit control operation

to insure accurate and safe process operation.

3. Check all electrical connections periodically and retighten connec-

tions which may have loosened in service. Replace wire and wire

terminals which show signs of oxidation which would interfere

with establishment of reliable electrical connections.

Figure 3 - NWH-6

480V, 3Ø ss

Figure 1 - NWH-6

480V, 2-3Ø ss

Contactor

Thermostat

120V, 240V

Contactor

Thermostat

1L1

1L2

1L3

2L1

2L2

2L3

120V

240V

WIRING (cont.d’)

NOTE: Dotted lines indicate “customer furnished.” However, Thermostat could have been furnished by Chromalox if so specified on the order.

2150 N. RULON WHITE BLVD., OGDEN, UT 84404

Phone: 1-800-368-2493 www.chromalox.com

TA - Y2 - EF

Litho in U.S.A.

RENEWAL PARTS IDENTIFICATION

Heating

Model VoltsPhase kW

Elements

NWH-62415 240 2-3Ø 24 155-115848-016

NWH-62415 480 2-1Ø 24 155-115848-017

NWH-62415 480 3Ø 24 155-115848-018

NWH-63015 240 2-3Ø 30 155-115848-020

NWH-63015 480 2-1Ø 30 155-115848-021

NWH-63015 480 3Ø 30 155-115848-022

NWH-64015 240 2-3Ø 40 155-115848-024

NWH-64015 480 2-3Ø 40 155-115848-025

NWH-65015 480 2-3Ø 50 155-115848-027

NWH-66015 480 2-3Ø 60 155-115848-029

PARTS COMMON TO ALL HEATERS

AR-215A Thermostat . . . . . . . . . . . . . . . . . . . . . . .300-057502-015

AR Mounting Bracket . . . . . . . . . . . . . . . . . . . .027-011378-001 (2)

Flexitallic Gasket . . . . . . . . . . . . . . . . . . . . . . . . .132-073008-013

Standard Gasket . . . . . . . . . . . . . . . . . . . . . . . . . .132-017222-003

Note: When ordering parts for Model Numbers suffixed by “XX” or any other letter

or letters, order Renewal Parts on special order basis. Give the name of the part, volt-

age, wattage and any other special features to your Chromalox Representative or the

factory.

Note: Number in ( ) indicates quantity of same part number used.

Limited Warranty:

Please refer to the Chromalox limited warranty applicable to this product at

http://www.chromalox.com/customer-service/policies/termsofsale.aspx.

Chromalox NWH Installation guide

Chromalox NWH Installation guide

Chromalox NWH Installation guide

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