Zinsco and Zinsco-Sylvania circuit breakers of the design described here do not offer the level of over current and fire protection provided by most other electrical panels and circuit breakers. This means homes with this equipment are at greater risk of fire or other electrical hazard.  Where Zinsco electrical panels and Zinsco circuit breakers are in use, arcing, contact-point burn, and even circuit breaker case blow-out have been observed in the field. 

A principal Zinsco circuit breaker (or Sylvania or GTE-Sylvania or Kearney electrical panel using this circuit breaker) point of failure appears to be at the point of contact where the circuit breaker contacts clip onto the electrical panel bus, combined with the use of an aluminum electrical panel bus.

In addition to advice on identifying Zinsco panels, inspecting Zinsco electrical panels, and repair/replacement advice, we provide field photographs of circuit breaker failures: overheating, burnups, failures to trip, overcurrent protection failure. This document includes field reports of failures and additional anecdotal evidence. Information found at Inspectapedia.com
 

Leaks Plague Polybutylene Plumbing

A controversy regarding the use of polybutylene pipe (PB) raises concerns about its reliability and use. The problem is the pipes often sprout leaks, to the dismay of many home owners who have the material installed in their homes

Poly piping is not installed with any glue, welds, or solder. This is a great feature, due to the lack of hazardous or flammable steps to install the material, there is less of a fire risk.  During construction of two homes at the Dos Lagos project in Corona California, we had a plumber who was sweating copper and forgot to have a fire extinguisher handy. Well the mistake cost us two homes and month's in time.  Poly piping is also light, which makes it easier on labor costs. The material is drastically cheaper than your standard copper piping. This important as copper prices rise, not only initial costs but also because builders can barely keep the copper in the storage bins a day before its stolen and never sees the inside of a house.  The down sides of using the material is that is new and there is an expensive learning curve.

Sufficient numbers of homeowners have shared this unnerving experience to provoke various lawsuits. Consumer complaints in Texas prompted the largest class action in U.S. history against the manufacturers of PB. This action resulted in a $750 million settlement.

In Arizona, two lawsuits are pending in Maricopa County Superior Court to recover damages from PB manufacturers for Arizona homeowners with PB failure. One of the cases is a class action suit similar to the one filed in Texas.

Average costs for PB-related home repairs are about $4,000, says Carl Triphahn of the Piping Industry Progress Education Trust, a contractor's organization in Phoenix. In some cases, homeowners are finding that homeowners insurance companies will either cancel their coverage when extensive damage is caused by PB or refuse coverage to homes piped with PB.

PB is a flexible, easy-to-cut gray plastic that is put together with simple crimp connectors. Introduced in the late 1970s, PB has been used to pipe approximately six million homes in the U.S. While it is unclear how many homes in Arizona have PB, an estimated 80,000 Arizonans have had problems with PB. Homeowners often cannot determine what type of plumbing they have by inspection, as stubs to sinks and toilets generally use poly-to-copper connectors.

Despite the decidedly bad news associated with PB use, manufacturers and other defenders of PB piping insist the product on the market today doesn't deserve its bad reputation. Manufacturers of raw PB, including Shell Oil, Hoeschst Celanese Corp., and Dupont De Nemours, blame the bulk of leaks and ruptures on improper installation.

PB manufacturer spokesperson Carrie Chassin says, "The main problem has been at the joints. Some plumbers just took old brass fittings and used them for plastic -- that's one piece of the puzzle." Chassin says the makers of PB piping have corrected problems with leaks.

PB manufacturers sponsor the Plumbing Claims Group (PCB) to replace plumbing for homeowners with leaking PB pipes. Despite manufacturers' assurances that PB is reliable, PCG uses only C-PVC, an indoor version of polyvinylchloride, a more rigid plastic piping with glued joints, in its repairs. Homeowners sign a binding agreement that releases the companies from further claims and requires repairs be done by plumbers chosen by PCG.

A contractor familiar with PB problems says ninety percent of all leaks are at joints in the piping. The contractor figures that about thirty percent of the problems at leaking joints are due to installation errors. Leaks occurring inside a line are almost always in hot water lines, sometimes in areas with no stress.

PB manufacturers have addressed joint problems with a new type of manifold design, which eliminates the use of T-joints and other traditional fittings used with copper and C-PVC pipes. Also known as the "manablock" system, the new design runs flexible 3/8 inch PB pipes from one common source to each fixture. Pipes are joined with a copper tube secured by two crimped copper bands to seal the connection.

Some contractors are not convinced that the copper bands are the solution to the problem. There have been complaints of leaking shutoff valves located at individual fixtures in the manifold system. Carl Triphahn says that the biggest failures in the new manifold design is that the PB tubing itself has been splitting.

Tom Sagau, Tucson City Council member and a plumbing contractor, disagrees. He claims the problems in the improved manifold system are the result of faulty fittings from improper installation. The new copper fittings are an improvement over the old PB joints, said Sagau, but "crimps need constant calibration to make sure [copper bands] are not too tight." If bands are crimped too snugly, excessive pressure on PB results and leaks are more likely to occur.

As debate continues about whether and to what extent faulty installation contributes to PB failure, another PB issue is getting attention -- whether chlorine added to water supplies deteriorates PB causing weakness or holes in the pipes.

PB manufacturers contracted H.D.R. Engineering Inc., a Bellevue, Washington company, to study the effects of chlorine on PB joints. "There's been some evidence," says Steve Reiber of H.D.R., "that the actual polymers that have been used to form some of the joint materials used with the plastic pipe, have a lack of resistance to some of the chlorine species common in distribution water systems."

Reiber found that "some forms of oxidants [e.g., chlorine] are more adverse than others and cause exfoliation that weakens the structure. Because [the joints] are under tension, it causes a leak." In other words, the pre-manifold PB joints, which were made from different plastics than the pipe itself, did deteriorate in the laboratory in the presence of chlorine.

Reiber says he has not looked at the susceptibility of the pipe to deterioration in the presence of chlorine. "To my knowledge, nobody has checked the pipe itself," he said.

Meanwhile, PB piping remains popular among many home builders because it offers savings of $200 to $600 per home compared to C-PVC and copper piping. PB piping is almost the exclusive material used in plumbing inexpensive tract houses and mobile homes. The piping itself is about half the cost of copper, but somewhat more expensive than C-PVC. Major cost savings come from lower installation costs -- PB can be installed quickly by semi-skilled labor.

Some plumbers were attracted to PB because customers cannot do their own repairs. The crimping tool required to seal joints is difficult to find in stores or rental shops.

Several Arizona municipalities have become sufficiently wary of PB to ban its use in new construction. Glendale and Goodyear left PB out of their new 1994 plumbing codes, and Chandler has banned the piping.

"We have not used PB in our city system," said Tom Mundinger, a Tucson Water design supervisor, "because there were some settlements in California early on, and there have been other types of pipes we've been happy with." Polybutylene however was approved for private use in Tucson, and the City Council added it to the uniform plumbing code in 1991.

Caution seems to be the final word with regard to PB use. "When the stuff first came out in the 1970s, we had our doubts about it," said Wayne Bryant, a marketing representative for the Plumbers & Steamfitters Local 741 in Tucson. "It was a buyer beware type deal," Bryant says and he believes buyers still need to beware.  Source http://ag.arizona.edu/AZWATER/awr/nov94/leaks.html