Chromalox Nwh 31225 Users Manual PE405 6 CHX

NWH-3925 IM-PE405

NWH-31225 im-pe405

NWH-3925 to the manual 2b0d73c3-cef8-4629-8a0a-e87394d5a1bb

: Chromalox Chromalox-Nwh-31225-Users-Manual-364657 chromalox-nwh-31225-users-manual-364657 chromalox pdf

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Dimensions (In.)

Watt

Model Voltage Phase kW Density ABC

NWH-3625 1 or 3Δ6 47.7 32-15/16 22-1/2 16-1/2

NWH-3925 1 or 3Δ9 47.5 32-15/16 22-1/2 16-1/2

NWH-31225 1 or 3Δ12 46.2 42-15/16 32-1/2 26-1/2

NWH-31525 1 or 3Δ15 45.9 55-7/16 45 39

NWH-31825 1 or 3Δ18 45.6 55-7/16 45 39

Chromalox

®

DIVISION

4

SECTION

NWH

SALES

REFERENCE

DATE

SERVICE REFERENCE

Installation Operation

and

RENEWAL PARTS IDENTIFICATION

PE405-6

JULY, 1990

(Supersedes PE405-5)

161-048380-001

GENERAL

INSTALLATION

© 2010 Chromalox, Inc.

Type NWH-3

Circulation Heater

for Water Heating

The NWH-3 series is a general-purpose water or water-based

solution circulation heater intended for use indoors. It is designed

for 150 psig at 550˚F per ANSI standards.

The 3 copper-sheathed tubular elements are centered in a 3”

diameter galvanized steel heating chamber and welded to a

removable galvanized steel flange. The assembly is surrounded

by 1-1/2” insulation and sheet metal jacket.

Depending upon the order specifications, the NWH-3 may or

may not be factory equipped with an AR or other Chromalox

thermostat. Such thermostats function to control outlet tempera-

tures and to limit internal temperatures under abnormal flow con-

ditions. These controls do not fail safe.

CAUTION: Users should install adequate back-up controls

and safety devices with their electric heating equipment.

Where the consequences of failure may be severe, back-

up controls are essential. Although the safety of the

installation is the responsibility of the user, Chromalox

will be glad to make equipment recommendations.

CAUTION

: Hazard of Electric Shock. Disconnect all

power before installing heater.

1. Vertical Mounting (Preferred) —

When the heater is vertically mounted, the terminal housing

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

Specifications — Table A

Incorrect

Correct

Figure A — Vertical Mounting Figure B — Horizontal Mounting

Correct

Incorrect

AC

B

F

12-5/16”

Thermostat

Type AR

Mounting Lugs

3/8” - 16

Threaded Holes -

1-1/2” Deep

1-1/4” Centers

1” Pipe Inlet

1” Pipe

Outlet

1-3/8” Conduit

Openings

D

240

or

480

E

OPERATION

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

sheath or the heating chamber.

WARNING: Type NWH Circulation Heaters are

equipped with copper heating elements and galva-

nized-steel heating chambers. It is the responsibil-

ity of the user to know the chemical composition

of the corrosive solution and the character of the

materials entering the solution as well as the cor-

rosive effect of the solution upon the heating ele-

ments and chamber. Chromalox cannot warrant

any electric circulation heater against failure by

sheath corrosion if such failure is the result of

operating conditions beyond our control.

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

condensation, spray or direct spill-over of material. Their

presence at the terminals may damage heater electrical insula-

tion. Liquid-tight terminal enclosures are available to protect

heater. Contact your Local Chromalox Sales office.

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

filters in the inlet pipe line to the heater.

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

MAINTENANCE

1. WARNING:

Hazard of Electric Shock. Disconnect all

power before servicing heater.

2. Remove heating element assembly periodically to check

heater sheath for scaling, corrosion or excessive oxidation.

Correct operating conditions to minimize sheath deterioration.

3. Periodically check temperature control and limit control oper-

ation to insure accurate and safe process operation.

4. Check all electrical connections periodically and retighten

connections 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.

WIRING

WARNING: Hazard of Electric Shock. Any installation

involving electric heaters must be effectively ground-

ed in accordance with the National Electrical Code to

eliminate shock hazard.

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

2. Electric wiring to heater must be installed in accordance with

local and National Electrical Codes.

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 Diagram, Table B, for the proper wiring diagram

for connecting

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-3 is provided with mounting lugs to support the heating

chamber. (See photo.)

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

the heater chamber will be permitted to expand with increas-

ing temperature.

5. DANGER: Hazard of Fire. Provide minimum of 6” spac-

ing from chamber and related piping to nearest combustible

material. Avoid operation of heater near combustible fluids or

in combustible vapor or gas laden atmosphere.

6. Provide adequate space at terminal end to permit withdrawal

of the heater from chamber should servicing be required.

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

1 Ø Fig. 3 Ø ΔFig. 1 Ø ΔFig. 3 Ø ΔFig.

NWH-3625 2 1 2 1

NWH-3925 2 1 2 1

NWH-31225 2 1 2 1

NWH-31525 2 1 2 1

NWH-31825 2 1 2 1

Ground

Contactor

Thermostat

L1

L2

L3

120V

or

240V

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

Figure 1

240V, 480V 3ØΔ

Figure 2

240V, 480V, 1Ø

Use contactor when the heater amperage

exceeds the rating of the thermostat.

Ground

Contactor

Thermostat

Line

120V

or

240V

AR2525 MF7

Model Volts Phase kW Heating Elements Thermostat Assembly Thermostat Assembly

NWH-3625 240 1 6 155-024796-001 300-057560-007 300-048481-006

NWH-3625 240 3Δ6 155-024796-002 300-057560-007 300-048481-006

NWH-3625 480 1 6 155-024796-003 300-057560-007 300-048481-006

NWH-3625 480 3Δ6 155-024796-004 300-057560-007 300-048481-006

NWH-3925 240 1 9 155-024796-006 300-057560-007 300-048481-006

NWH-3925 240 3Δ9 155-024796-007 300-057560-007 300-048481-006

NWH-3925 480 1 9 155-024796-008 300-057560-007 300-048481-006

NWH-3925 480 3Δ9 155-024796-009 300-057560-007 300-048481-006

NWH-31225 240 1 12 155-024796-011 300-057560-007 300-048481-006

NWH-31225 240 3Δ12 155-024796-012 300-057560-007 300-048481-006

NWH-31225 480 1 12 155-024796-013 300-057560-007 300-048481-006

NWH-31225 480 3Δ12 155-024796-014 300-057560-007

NWH-31525 240 1 15 155-024796-016 300-057560-007 300-048481-006

NWH-31525 240 3Δ15 155-024796-017 300-057560-007 300-048481-006

NWH-31525 480 1 15 155-024796-018 300-057560-007 300-048481-006

NWH-31525 480 3Δ15 155-024796-019 300-057560-007 300-048481-006

NWH-31825 240 1 18 155-024796-021 300-057560-007 300-048481-006

NWH-31825 240 3Δ18 155-024796-022 300-057560-007 300-048481-006

NWH-31825 480 1 18 155-024796-023 300-057560-007 300-048481-006

NWH-31825 480 3Δ18 155-024796-024 300-057560-007 300-048481-006

RENEWAL PARTS IDENTIFICATION

PARTS COMMON TO ALL HEATERS

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

Flexitallic Gasket . . . . . . . . . . . . . . . . . . . . . .132-019779-001

Standard Gasket . . . . . . . . . . . . . . . . . . . . . . .132-017222-001

Note: When ordering parts for Model Numbers suffixed by “XX” or any other letter or letters not specifically identified on this instruction sheet, order Renewal

Parts on special order basis, giving name of part, part number, model number and description.

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

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

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

PL - U0 - T3

Litho in U.S.A.

Limited Warranty:

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

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