Okay, let's break down whether you can run MC cable inside a convector enclosure.

Generally, Running MC Cable Inside a Convector Enclosure is

NOT Recommended and May Violate Code.

Here's why, and what to consider:1. Purpose of Convector Enclosure

Convector enclosures are specifically designed to contain and direct the flow of heated air from the heating element (usually a hydronic convector). They are not intended to be raceways or enclosures for electrical wiring.2.

Heat Considerations

While you mentioned ambient temperature correction, the actual temperatures inside a convector enclosure can be significantly higher than normal ambient. This could easily exceed the temperature rating of the MC cable's insulation, leading to premature degradation, cracking, and potential short circuits or fire hazards. Even with derating, this is a risky practice.3.

Violation of Listing and Labeling

Convector enclosures are typically listed and labeled for a specific purpose (containing and directing heat). Introducing electrical wiring can void the listing and potentially create a safety hazard, especially if the enclosure isn't designed to handle electrical components.4.

Access and Maintainability

Running cable inside a convector can make it difficult to access the wiring for inspection, maintenance, or repairs. This violates general electrical code principles.5.

Securing and Support Issues

Convector enclosures are usually made of sheet metal and may not provide adequate and compliant points for securing and supporting the MC cable at required intervals. You would likely have to drill into the enclosure, which could affect its structural integrity, thermal performance, and UL listing.6.

Potential Code Violations

Running MC cable inside a convector enclosure is not a normal installation method and is likely to violate NEC articles regarding the proper use of raceways, enclosures, and cable installation.

What the NEC Says (General Guidance, always consult your local AHJ)



NEC 300.11 (Securing and Supporting)

Wiring methods must be securely fastened and supported. Convector enclosures are generally not designed for this purpose.

NEC 300.3(B) (Conductors of Different Systems)

Conductors of different systems shall not occupy the same enclosure, cable, or raceway unless specifically permitted elsewhere in the Code. While this doesn't directly address the convector issue, it highlights the general principle of keeping different systems separate.

NEC 110.3 (Examination, Identification, Installation, and Use of Equipment)

Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling. Installing wiring inside a convector would almost certainly violate the convector's listing.

NEC 310.15 Temperature Limitations. Conductors must be used within their insulation temperature rating. Running cable in a hot convector enclosure could easily exceed this limit.

Instead of Running MC Inside the Convector



Route the MC cable around the convector enclosure. Maintain appropriate clearances from the heated surfaces. Use surface-mounted raceway (e.g., Wiremold) to route the cable neatly along the wall near the convector. If you absolutely must pass through the convector enclosure (which is highly discouraged), use a properly sized metal conduit nipple with appropriate fittings (e.g., EMT, IMC, or Rigid) to create a "bridge" through the enclosure. The conduit should be securely supported independently of the convector. However, I would still strongly advise against this. Consult with your local electrical inspector (AHJ) for guidance on acceptable alternative wiring methods in your specific situation.In Summary:

Running MC cable directly inside a convector enclosure is almost certainly a code violation and a poor practice due to heat, listing limitations, access concerns, and securing issues. Explore alternative wiring methods that keep the electrical wiring separate from the heating appliance and its enclosure. Always consult your local AHJ for approval of your wiring plan. They have the final say. Flag for review