Yes. Just don’t be sloppy about it.

Can you run a wire through an air duct?

Air ducts are meant as a conduit for air, not wires. Inserting cables inside the ductwork may even violate building codes. The reason we don’t advise this is because a technician can damage the cables during an air duct cleaning.

Is plenum the same as duct?





A plenum is an air distribution box designed for forced-air systems on residential homes and commercial businesses. It is part of the ductwork, but far different than an air duct as these important boxes handle air as it enters the ducts and helps to recirculate it within a system.

Can you run duct work on an outside wall?

It’s mainly an older-house problem
The bad news is that if you have an older home with your supply vents in the exterior walls, you ought to plan some way of addressing the problem. The best thing to do is open the wall and remove the duct and boot, do your air-sealing, and then insulate.

Is it OK to run wire through cold air return?

Re: Electrical wire crossing cold air return duct
In any event it will not hurt anything to be on the safe side.

Is Romex plenum rated?

Regular type NM cable (what’s generally called Romex) is not plenum rated. Type AC cable (often incorrectly called BX) is allowed in plenums, however. The main concern is the toxic fumes that the plastics used in most wire insulation release when they’re heated or burned.

Should an AC plenum be insulated?





Supply and return air ducts and plenums shall be insulated with a minimum of R-6 insulation where located in unconditioned spaces and where located outside the building with a minimum of R-8 insulation in Climate Zones 1 through 4 and a minimum of R-12 insulation in Climate Zones 5 through 8.

How big should a supply plenum be?

Single plenums should not exceed 24 ft in length. Double plenums should not exceed 48 ft in total length.

What is the purpose of a plenum?

Plenum boxes are usually situated on either side of the fan or heat exchanger and have the important function of bringing in, distributing, and removing air. They are the air’s first stop after being heated or cooled and its last stop before going back into your AC, heat pump, or furnace.

Can MC cable touch ductwork?

Armored cable is meant to resist damage to the conductors from contact with other materials (like a duct). The armor itself is grounded when properly installed, and touching other metal should pose no risk (assuming the armor is not so bent or compressed as to expose the conductors).

Can dryer vent touch electrical wires?



Long, complex dryer vents are just an invitation to problems. Having it touching the wires is likely to overheat that portion of the wires each time the dryer operates, so at minimum providing some insulation between the two would be better.

Is metal clad cable plenum rated?

In summary, it is important to know that while Interlocked Metal-Clad Cable, without any PVC jacketing, is not technically “Plenum” rated it is perfectly acceptable to be located in an environmental air space, such as the space above a suspended or dropped ceiling in accordance with National Electrical Code section

What’s the difference between plenum and non plenum?

Thus, fire and building safety codes mandate plenum-rated cables be used in plenum spaces and air ducts. They can also be used in non-plenum areas. Non-Plenum cables, on the other hand, are much cheaper and not as fire-resistant. When burned, they release toxic fumes such as hydrochloric acid and dioxin.

Can you run Ethernet through heating ducts?



You should never run an ethernet cable through the vents in your home. The heated air in your vents can damage the wires, which will interrupt your internet service and release toxic fumes from the cable’s plastic casing.

Is nm b plenum rated?

Section (B) Ducts or Plenums Used for Environmental Air. Basically NM Or Non-Metallic sheathed cable (Romex) is not allowed. The reason being, is that if it were exposed to fire or excessive heat the molded plastic cover and wire insulating would break down.

Which wire type can you run in a plenum?

Plenum cables are coated with flame retardant and made using special plastics that don’t smoke nearly as much as other plastics to help prevent this problem. Any cable that you run through plenum spaces must be plenum rated, even wiring used for information transfer, like Cat5 wiring.

Can you run Romex through cold air return?

On the other hand, it’s common practice to run Romex perpendicularly across a panned stud cavity or joist bay used as a cold air return duct. In such a case, we drill into the framing on both sides of the panned return, pull the cable through the holes, then seal the holes around the Romex with caulk.

Where is Romex not allowed?



To give you an overview of what the National Electrical Code (NEC) regulations state, Romex wire shouldn’t be left exposed anywhere in the house, be it the basement, attic, or the home itself. In other words, the installation above is not compliant with the relevant codes.

Can you bury Romex without conduit?

Buried or exposed wiring will need to be listed for its application. Underground feeder wiring can be directly buried without a conduit with a minimum of 24 inches of cover. Any wiring placed inside intermediate metal or rigid metal conduits will require at least six inches of ground cover.

Is it legal to run Romex in conduit?

No, you can not run your Romex wiring in conduits. What you’re looking at in the code book is referring to THHN and other wiring, that while insulated with a single coat is not insulated with a second covering and bound to 2 or 3 other wires.