Chromalox NWH-185015 specifications Wiring, Operation, Horizontal Mounting Optional

INSTALLATION

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)

Correct

Incorrect

Figure B — Horizontal Mounting

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-18 is provided with mounting lugs to support the heat- ing chamber. (See photo on previous page)

4.By using a slotted mounting assembly on either of the mount- ing lugs, the heater chamber will be permitted to expand with increasing 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 atmospheres.

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

WIRING

WARNING: Hazard of Shock. Any installation involving electric heaters 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.Electric wiring to heater must be installed in accordance with local and National Electrical Codesby a qualified person as defined in the NEC.

3.Power controllers must be used when heaters are rated for 480 volt service or if the amperage rating of the heaters exceeds the contact rating of the thermostat.

4.Refer to Wiring Diagram Table B for the proper wiring dia- gram for connecting heater.

Table B — Wiring Diagrams

Heater Model	240V 3 Phase Fig.	480V 3 Phase Fig.
NWH-185015	1	2
NWH-187515	1	2
NWH-1810015	1	2
NWH-1812515	1	2
NWH-1815015	1	2
NWH-1817515	1	2
NWH-1820015	1	2

L3

L2

Contactor L1

Contactor

Contactor

120V or

240V Thermostat

Figure 1 – 240V 3-3 ø

L3

L2

L1

Contactor

Contactor

Contactor

120V or

240V Thermostat

Figure 2 – 480V 3-3 ø

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

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 galvanized-steel heating chambers. It is the responsibility 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 corrosive effect of the solution upon the heating elements and chamber. Chromalox cannot warrant any electric circula-

tion heater against failure by sheath corrosion if such failure is the result of operating condi- tions 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. Check Factory.

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.