The answer to 'natural carpenter ant repellent' is to use natural deterrents like cinnamon, diatomaceous earth, or vinegar. These can help repel carpenter ants without using harsh chemicals. Sprinkle cinnamon or diatomaceous earth around entry points and affected areas, and wipe down surfaces with undiluted vinegar. You'll need to reapply these natural repellents regularly, as their effects are temporary.
If the infestation is severe or continues after trying natural methods, it's best to call in a professional pest control technician. They can properly identify the ant species, locate the nest, and use targeted treatments to eliminate the problem.