Wiring, Operation, Maintenance | Chromalox NWH-31525, NWH-31825

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.

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

Model	240V,		240V,	480V,	480V,
Model	1 Ø	Fig.	3 Ø Δ Fig.	1 Ø Δ Fig.	3 Ø Δ Fig.
	1 Ø	Fig.	3 Ø Δ Fig.	1 Ø Δ Fig.	3 Ø Δ Fig.
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

Contactor

Ground	L1
	L1
	L2
	L3
	120V
	or
	240V
	Thermostat

Figure 1

240V, 480V 3ØΔ

Ground

Figure 2

240V, 480V, 1Ø

Contactor

Line

120V

240V

Thermostat

Use contactor when the heater amperage exceeds the rating of the thermostat.

Note: Dotted lines indicate “customer furnished.” However, Thermostat could have been 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 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.

NWH-31525, NWH-31825, NWH-31225, NWH-3925, NWH-3625 specifications

Chromalox is a leader in thermal technologies, renowned for manufacturing high-quality heating solutions tailored for various industrial applications. Among their extensive product offerings are the NWH series heaters, which includes models NWH-3625, NWH-3925, NWH-31225, NWH-31825, and NWH-31525. These units are designed to deliver exceptional performance and reliability in demanding environments.

The NWH series heaters feature robust construction and are engineered to withstand challenging conditions. Made from durable materials, these heaters are resistant to corrosion, ensuring long-term operational life. One of the standout characteristics of these models is their ability to provide precise temperature control, which is critical in applications requiring stringent thermal management.

Each model in the NWH series is equipped with advanced heating technologies, including high-efficiency heating elements that allow for rapid heat-up times and consistent temperature maintenance. This efficiency not only improves performance but also reduces energy consumption, making the NWH heaters an environmentally friendly choice.

In terms of operational versatility, the NWH series heaters are designed for a wide range of applications, from process heating and fluid heating to equipment protection. Their compact design enables easy integration into existing systems, while their robust electrical and mechanical configurations provide the necessary flexibility for various installations.

Safety is paramount in the design of Chromalox heaters. The NWH models incorporate multiple safety features, such as built-in thermal cutoffs and over-temperature protection, which safeguard both the equipment and personnel in industrial settings.

Additionally, these heaters are equipped with user-friendly controls, allowing for seamless operation and monitoring. The digital displays provide real-time feedback, facilitating timely adjustments and ensuring optimal performance.

In summary, Chromalox NWH-3625, NWH-3925, NWH-31225, NWH-31825, and NWH-31525 heaters represent the pinnacle of thermal technology. Their combination of efficiency, reliability, and safety features, along with their capacity for precise temperature maintenance, make them ideal solutions for a variety of industrial heating applications. Investing in these models ensures not only effective thermal management but also contributes to a more sustainable operational approach, aligning with modern industrial demands.