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Insulation Problem

The purpose of insulation is to safeguard older wiring from the heat generated by a light fixture. Newer homes come equipped with wiring rated for higher temperatures, hence any additional insulation purchased should be non-combustible. Insulation problems and insulation questions can arise during new construction or when one has to deal with existing wiring or fixtures requiring an insulation repair due to age or damage. Insulation repair can be carried out mainly with the use of insulation parts and materials such as electrical tape, heat shrink tubing or PVC insulation tape.

To know more about insulation problems, below are a few questions answered by Experts.

When a 14/2 exterior insulation is stripped, is the exposed conductor insulation suitable for direct burying?

This is dependent on how the connections were spliced together. If the splices were made using silicone loaded wire nuts and a little portion of the outer insulation was removed to allow the nuts to fit, there may be further digging required. The only approved splice that is required in this case is called the UF splice kit. This is available at most electrical supply houses or home improvement stores. They enable adhesive heat shrink to cover the splice. This subsequently helps seal the connection completely, to restore the UF rating.

The septic wiring insulation failed after three years. Please provide insulation information for connected wires inside a septic tank.

Typically a septic tank should not have an exposed taped joint or an internal outlet because fumes and moisture from the tank are corrosive and detrimental to the wiring. The insulation parts or material present inside the tank should be of stainless steel or plastic. Hence one of the best solutions or insulation options is to have a J-box which is not part of the septic tank. Usually the installations are such where a weather proof PVC box is used inside the tank along with plastic weather proof connectors. In this case, direct bury rated wire nuts should be used.

Is there another insulation part available which can be substituted for flush mount lighting?

Insulation on light fixtures is important and necessary. Its main purpose is to prevent the wiring from overheating. As an alternate the insulation part which can be replaced on the fixture is fiberglass. To do so, a piece of this fiberglass of the same diameter or size as the fixture canopy should be cut. If the thickness of the piece is approximately two inches, it should be sufficient to complete the insulation on the flush mount lighting fixture.

Are there any rules regarding spray foam insulation and electrical wiring?

This type of insulation does not violate any electrical code and is very commonly used in most new homes. Typically a majority of the insulation sprays available in the market are acceptable to be used with NM or Romex type of wiring. It would be a good idea to check the label of the product which is being used as most will have clear instructions and indications on which are compatible to use with different type of wiring.

How can an insulation test on branch circuit wiring be undertaken in a home without opening the drywall or without any destruction?

One of the options which suit this need is to use a Megger type insulation checker. The cost of these are a few hundred dollars however, Chinese branded ones are available on Ebay for as less as $100. The more expensive models are meant for specific calibrated use, mainly meant for the purpose of Compliance Certificate issuance. In order to go about this, the neutral and ground should be disconnected from the buss or hot to ground and/or neutral. Next with the breaker off, from either end, one should measure between the three conductors. Another option would be to measure between hot and ground alone when all the wires are connected and the breaker is off. The ideal reading should be 1 million OHMS. Any figure less than 200,000 is an indication of a problem.

As seen above there can be several insulation questions which can arise at different junctures. These issues and problems need to be addressed with insulation information because insulation is an important safety requirement. To understand any particular insulation problem being faced or seek insulation repair tips, seeking assistance and expertise of Experts may be necessary. They can provide specific and useful answers to most insulation questions.
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