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SOUTHWIRE Thermostat Wire: 18 AWG Conductor Size, 4 Conductors, 250 ft Overall Lg - Plenum-Rated Thermostat Wires
SOUTHWIREPlenum-Rated Thermostat Wires

SOUTHWIRE Thermostat Wire: 18 AWG Conductor Size, 4 Conductors, 250 ft Overall Lg

The SOUTHWIRE Thermostat Wire (MPN 555040423) is a CL2P plenum-rated cable with 18 AWG conductors, 4 conductors, 250 ft overall length, and 300 V rating. 3G Electric interprets your demand for this specific wire…

SKU 3G-OTH-48574

Brand
SOUTHWIRE
Item
Thermostat Wire: 18 AWG Conductor Size, 4 Conductors, 250 ft Overall Lg
Category
Plenum-Rated Thermostat Wires
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

SOUTHWIRE
Manufacturer Part Number
555040423
Type
CL2P
Overall Lg
250 ft
Volt
300 V
Conductors
4

Technical Documents

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SOUTHWIRE Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SOUTHWIRE Thermostat Wire (MPN 555040423) is a CL2P plenum-rated cable with 18 AWG conductors, 4 conductors, 250 ft overall length, and 300 V rating. 3G Electric interprets your demand for this specific wire, sources it from our supply network, provides a firm quote, and supports your installation with specialist expertise across 14 industrial departments — including combustion, pumps, and controls — ensuring you get the right answer, not just a catalog.

Frequently Asked Questions

What is Southwire thermostat wire used for?

Southwire thermostat wire connects HVAC thermostats to heating, cooling, and ventilation equipment. The 18 AWG, 4-conductor, 300 V, CL2P-rated cable is suitable for plenum spaces where fire safety is critical, ensuring reliable signal transmission in commercial and residential systems.

What are the specifications of Southwire thermostat wire 555040423?

This Southwire thermostat wire has 18 AWG conductor size, 4 conductors, 250 ft overall length, 300 V voltage rating, and CL2P plenum rating. The manufacturer part number is 555040423. It is designed for low-voltage control circuits in HVAC applications requiring fire-resistant insulation.

Where to buy Southwire thermostat wire worldwide?

3G Electric supplies Southwire thermostat wire worldwide, handling full logistics and customs clearance for international orders. As a global industrial solutions provider, we source and deliver genuine Southwire products to your location. Contact us for pricing and lead time on this 555040423 cable.

How to install Southwire thermostat wire?

Install Southwire thermostat wire by routing it through plenum spaces per local electrical codes, using proper supports and avoiding sharp bends. Strip insulation carefully to expose conductors, and connect to thermostat and HVAC terminals per manufacturer wiring diagrams. Always verify voltage is off before handling.

Used in

Common applications for SOUTHWIRE
Commercial construction — Southwire THHN/THWN-2 building wire (750 kcmil) for feeder circuits in conduit systems
Industrial maintenance — Southwire 8 AWG THHN/THWN-2 for motor branch circuits in wet locations
Outdoor job sites — Southwire 50 ft extension cord (12/3 SJTW, L5-20P) for powering 20 A equipment
Fixture wiring — Southwire 18 AWG TFFN wire for control panels and lighting fixtures in dry environments
Temporary power distribution — Southwire 25 ft extension cord (14/3 SJTW) for portable tools on construction sites
Workshop lighting — Southwire AL60CSW LED work light for high-bay illumination in maintenance bays

SOUTHWIRE Products

3G Electric supplies SOUTHWIRE plenum-rated thermostat wires. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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Compatible alternatives & equivalents

Cross-referenced by specification & description
This 8-conductor, 18 AWG thermostat wire is rated 150 V and CL2 for nonplenum installations. It is used for low-voltage control wiring in HVAC systems, such as connecting thermostats, zone valves, and boiler controls. The 250 ft length supports residential and commercial wiring runs
SOUTHWIRE
This 8-conductor, 18 AWG thermostat wire is rated 150 V and CL2 for nonplenum installations. It is used for low-voltage control wiring in HVAC systems, such as connecting thermostats, zone valves, and boiler controls. The 250 ft length supports residential and commercial wiring runs
CL2-rated thermostat wire for low-voltage control circuits in nonplenum spaces. Four 22 AWG conductors, 150 V rating, 250 ft length. Suitable for connecting thermostats to HVAC equipment such as furnaces, air conditioners, and heat pumps in residential and light commercial systems
SOUTHWIRE
CL2-rated thermostat wire for low-voltage control circuits in nonplenum spaces. Four 22 AWG conductors, 150 V rating, 250 ft length. Suitable for connecting thermostats to HVAC equipment such as furnaces, air conditioners, and heat pumps in residential and light commercial systems
CL2-rated thermostat wire for low-voltage HVAC control wiring in non-plenum spaces. Features 4 conductors, 150 V rating, and 250 ft length. Suitable for thermostats, zone valves, and heating/cooling equipment
SOUTHWIRE
CL2-rated thermostat wire for low-voltage HVAC control wiring in non-plenum spaces. Features 4 conductors, 150 V rating, and 250 ft length. Suitable for thermostats, zone valves, and heating/cooling equipment
This nonplenum-rated thermostat wire features 8 conductors with 18 AWG size, rated for 150 V and CL2 classification. The 250 ft length supports wiring for HVAC thermostats, zone valves, and boiler controls in residential and light commercial installations
SOUTHWIRE
This nonplenum-rated thermostat wire features 8 conductors with 18 AWG size, rated for 150 V and CL2 classification. The 250 ft length supports wiring for HVAC thermostats, zone valves, and boiler controls in residential and light commercial installations
This nonplenum-rated thermostat wire is used for low-voltage control wiring in HVAC systems, connecting thermostats to heating and cooling equipment. It features 4 conductors, a 250 ft overall length, and a 150 V voltage rating. Suitable for residential and commercial installations where CL2-rated cable is required, such as in walls or ceilings
SOUTHWIRE
This nonplenum-rated thermostat wire is used for low-voltage control wiring in HVAC systems, connecting thermostats to heating and cooling equipment. It features 4 conductors, a 250 ft overall length, and a 150 V voltage rating. Suitable for residential and commercial installations where CL2-rated cable is required, such as in walls or ceilings
Nonplenum-rated thermostat wire with 5 conductors of 18 AWG, rated 150 V and 250 ft length. CL2 classification suitable for low-voltage control wiring in HVAC systems, including thermostats and zone valves, for non-plenum installations
SOUTHWIRE
Nonplenum-rated thermostat wire with 5 conductors of 18 AWG, rated 150 V and 250 ft length. CL2 classification suitable for low-voltage control wiring in HVAC systems, including thermostats and zone valves, for non-plenum installations

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CL2P plenum-rated thermostat wire for low-voltage HVAC control wiring. 3 conductors, 18 AWG, 500 ft length, 300 V rating. Suitable for installation in air-handling spaces without conduit per fire-safety codes
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CL2P plenum-rated thermostat wire for low-voltage HVAC control wiring. 3 conductors, 18 AWG, 500 ft length, 300 V rating. Suitable for installation in air-handling spaces without conduit per fire-safety codes
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CL2P plenum-rated thermostat wire for low-voltage HVAC control wiring. 2 conductors, 300 V rating, 500 ft length. Suitable for installation in air-handling spaces such as drop ceilings where fire safety and low smoke emission are required
CL2P plenum-rated thermostat wire with 8 conductors, 300 V rating, and 250 ft length. Suitable for low-voltage control wiring in HVAC systems, including thermostats and zone valves. Plenum rating permits installation in air-handling spaces without conduit
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CL2P plenum-rated thermostat wire with 8 conductors, 300 V rating, and 250 ft length. Suitable for low-voltage control wiring in HVAC systems, including thermostats and zone valves. Plenum rating permits installation in air-handling spaces without conduit
CL2P plenum-rated thermostat wire with 6 conductors, 300 V rating, and 250 ft length. Suitable for low-voltage control wiring in HVAC systems, including thermostats and zone valves, where fire safety is required for installation in air-handling spaces
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CL2P plenum-rated thermostat wire with 6 conductors, 300 V rating, and 250 ft length. Suitable for low-voltage control wiring in HVAC systems, including thermostats and zone valves, where fire safety is required for installation in air-handling spaces