Thermostat Wire 20AWG Solid Bare Copper CMR Brown – 2 5 6 8 Conductors

Install thermostat and HVAC control wiring in walls and risers with this 20AWG solid bare copper thermostat wire, rated CMR / FT4 and C(ETL)US Listed for code-compliant permanent installations in residential and commercial buildings. The 20AWG gauge is ideal for systems with shorter runs or lower current requirements — a practical, cost-effective option when 18AWG is more than your system needs.

Available in four conductor counts to match your system. The sunlight-resistant brown PVC jacket is the recognized industry standard color for thermostat wire, resistant to UV exposure, moisture, and temperature changes for both indoor and outdoor exposed runs. Color-coded conductors simplify wiring at every terminal. Each reel is clearly marked for easy identification on the job.

C(ETL)US Listed · CMR / FT4 · CL2 / CL2R · Sunlight Resistant

Common Specifications (all variants):
• Cable Type: Thermostat Wire, Riser (CMR)
• Conductor: Solid Bare Copper, 20AWG
• Insulation: Color-coded PVC
• Jacket: CMR-rated PVC, Brown, Sunlight Resistant
• Standards: CL2 / CL2R, CMR / FT4
• Certifications: C(ETL)US Listed

Conductor variants, OD, and recommended applications:
• 20/2 (0.172 in. OD, 500ft) — White/Red — Basic heating, doorbells, simple controls
• 20/5 (0.224 in. OD, 500ft or 250ft) — Blue/Green/White/Red/Yellow — Heat pumps, 5-wire systems
• 20/6 (0.191 in. OD, 250ft) — Blue/Green/White/Red/Yellow/Brown — Multi-stage HVAC, emergency heat
• 20/8 (0.256 in. OD, 250ft) — 8 color-coded — Smart thermostats, zoned HVAC systems

Note: For longer runs or high-current HVAC applications such as heat pump compressors, use 18AWG thermostat wire.