PE437-1, General, Installation | Chromalox NWHO(F)-27

Chromalox®

Installation

and

RENEWAL PARTS IDENTIFICATION

SERVICE REFERENCE

DIVISION 4		SECTION NWHO
SALES	(Supersedes PE437)		PE437-1
REFERENCE	(Supersedes PE437)		PE437-1
			161-303184-001

DATE APRIL, 1999

Type NWHO(F)-27 Series Circulation Heater

(for Regular and Fuel Oil Heating)

Thermostat (When Specified)

Specifications — Table A

Regular Oil Heaters

3 - 1-3/8" K.O. for 1" Conduit

3" Pipe

Outlet (Std.)

2 Mtg. Lugs Ea with Three 3/4" - 10 x1-1/8" Deep Holes on 1-3/4" Centers

3" Pipe Inlet (Std.)

15-15/16"

11"		A
		A
		3/4" NPT
		3/4" NPT
		Pipe Plug

	17-1/8"
	17-1/8"

					Dimensions (In.)

Model	Volts	Phase	kW	W/In2	A	B	C
NWHO-2780R15	240 or 480	3	80	20	77-9/16	52	48-1/2
NWHO-2790R15	240 or 480	3	90	20	81-9/16	56	52-1/2
NWHO-27100R15	240 or 480	3	100	20	87-9/16	62	58-1/2
NWHO-27120R15	240 or 480	3	120	20	97-9/16	72	68-1/2

		Fuel Oil	Heaters
NWHO-2750R15	240 or 480	3	50	12	77-9/16	52	48-1/2
NWHO-2760R15	240 or 480	3	60	12	87-9/16	62	58-1/2
NWHO-2770R15	240 or 480	3	70	12	97-9/16	72	68-1/2

Dimensions and ratings vary according to customer requirements.

Check engineering drawing for specifications.

F-Denotes heater is baffled, i.e., NWH0F

GENERAL

WARNING: This heater is not intended for use in haz- ardous atmospheres where flammable vapors, gases, liquids or other combustible atmospheres are present as defined in the National Electrical Code. Failure to comply can result in explosion or fire.

Hazardous area terminal enclosures are available, consult your local Chromalox representative for details.

The NWHO-27 series is a general-purpose oil circulation heater intended for use indoors.

The 27 or 36 steel sheathed tubular elements are welded to a remov- able steel flange and centered in a 10 inch diameter steel heating chamber.

Depending upon the specifications, the NWHO-27 may or may not be factory equipped with AR or other Chromalox thermostats. Such ther- mostats function to control outlet temperatures and limits internal tem- perature under abnormal flow conditions. These controls do not fail-safe. Thermocouples are also available as an option.

CAUTION: Users should install adequate back-up con- trols 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 installation is the responsibility of the user, Chromalox will be glad to make equipment recom- mendations.

INSTALLATION

WARNING: Hazard of Shock. Disconnect all power before installing heater.

1.Vertical mounting (axis of chamber vertical as in sketch above) is preferred. (Terminal housing at top of heater) (Figure A)

2.When mounting heater horizontally, inlet and outlet MUST be up. In any other position, heater cannot be purged of air and elements may be seriously damaged. (Figure B)

3.This series of circulation heaters are provided with mounting lugs to support the heater chamber. Refer to sketch above for location of these mounting lugs.

4.Mount heaters to permit unrestrained expansion of chamber due to temperature. This can be accomplished by using a slotted mount-

ing assembly on either of the lugs.

5.DANGER: Hazard of Fire. Provide minimum of 6” spacing from a chamber and related piping to nearest combustible materi- al. Avoid operation of heater near combustible fluids or in com- bustible vapor or gas laden atmosphere.

6.Provide adequate space at terminal end to permit withdrawal of the heater from chamber should servicing be required.

7.If two or more heaters are needed to provide the needed heating capacity, arrange them for series oil flow.

8.DANGER: Possible Explosion. A pressure relief valve should be provided by customer at outlet of vessel. There should be no other valving between vessel and valve.

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