Thermostat Wire 18/2 Brown Solid Copper 18 Gauge - 200 ft

In this review the Thermostat Wire 18/2 from THE CIMPLE CO is evaluated for homeowners and HVAC technicians who need reliable low-voltage control wiring. The bottom line: this simple brown, 18 gauge, 2-conductor cable is built for thermostat, air conditioning and security system runs where a solid copper conductor and riser rating matter. Its chief selling point is the combination of solid copper conductors and a UL listed, CMR riser-rated jacket that makes it a dependable, code-friendly choice for residential and commercial riser installations.

Key Features

• 18 AWG solid copper: Provides consistent conductivity and low resistance for thermostat and control circuits to minimize voltage drop over typical run lengths.
• 2 conductors: Ideal for simple thermostat and low-voltage control pairs where only a two-wire connection is required.
• CMR riser rated jacket: Allows safe vertical runs in multi-level buildings and meets riser installation requirements beyond basic CL2 ratings.
• UL listed: Gives confidence that the cable meets recognized safety standards for power-limited circuits.
• 200 ft length: Long spool reduces the need for joins on longer runs and is convenient for most residential or light commercial installations.
• UV and sunlight resistant jacket: Adds durability for indoor locations where incidental sun exposure or bright utility areas are a concern.

Who It's For

This cable is best for homeowners replacing thermostat wiring, HVAC installers running control circuits for heat pumps or air conditioning, and technicians wiring doorbells or basic alarm sensors. The combination of solid copper conductors and a riser-rated jacket suits mid-rise residential and light commercial projects where CL2 or CL3 substitution and NEC compliance are desired.

It is not intended for plenum spaces where CMP plenum-rated cable is required, nor for complex multi-conductor control panels that need more than two conductors or shielded cable. Customers who require stranded wire for frequent flexing should consider a stranded alternative.

Pros & Cons

Pros

• Solid 18 AWG copper conductors deliver reliable, low-resistance connections for thermostat and control circuits.
• UL Listed and CMR riser rating provide code-friendly use for vertical building runs.
• Long 200 ft length reduces waste and the need to splice for typical home installations.
• UV and sunlight resistant jacket improves durability in exposed indoor areas.

Cons

• Only two conductors; not suitable where three or more wires are required without purchasing additional cable.
• Not plenum rated, so it cannot replace CMP cable for ceiling plenum runs.

Specifications

Conductor	Solid copper
Gauge	18 AWG
Conductors	2
Length	200 ft
Jacket rating	CMR riser rated, UV resistant
Listings	UL Listed, suitable substitute for CL2/CL3 riser classifications

Our Verdict

The Thermostat Wire 18/2 is a practical, no-frills choice for anyone installing or repairing thermostat and basic HVAC control wiring who needs a riser-rated, UL listed solid copper cable. It offers good value with a long 200 ft spool and durable jacket, but those needing plenum rating or more conductors should select a different product.

Frequently Asked Questions

Can this cable be used for thermostat and HVAC control wiring?
Yes. The 18 AWG solid copper conductors and two-wire configuration are designed for thermostat and basic HVAC control circuits.

Is this cable plenum rated for ceiling runs?
No. This cable is CMR riser rated, not CMP plenum rated, so it should not be used in plenum air handling spaces.

Will the 200 ft spool avoid splices for a typical home?
In most single-family home installations the 200 ft length is sufficient to cover long runs without splices, reducing connections and potential failure points.