Exploring Subrogation Potential: Plumbing and Appliance Failures

Minor plumbing or appliance issues are part of everyday life for residential policyholders. But when water-carrying components and products catastrophically fail and create water losses, adjusters and carriers may want to consider component testing to evaluate subrogation potential.
 
Use this resource to explore common household plumbing and appliance failures that are linked to manufacturing defects or installation errors and can be identified by Component Testing Laboratories (CTL), part of Alpine Intel’s suite of services. Learn how Professional Engineers use specialized equipment and the scientific method to aid subrogation decisions.

Brass Fittings

Brass fittings connect water-carrying pipes throughout homes, making them an integral part of residential plumbing systems.

 

Common Failure Modes Found During Product Testing:

1

Stress Corrosion Cracking

2

Dezincification
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Stress Corrosion Cracking (SCC) in brass fittings typically occurs due to a material deficiency and produces fractures that may result in a water leak.

Brass Fittings

Brass fittings connect water-carrying pipes throughout homes, making them an integral part of residential plumbing systems.

 

Common Failure Modes Found During Product Testing:

1

Stress Corrosion Cracking

2

Dezincification
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Dezincification is a corrosion process in which copper remains in a brass alloy while zinc is leached away. Mild dezincification will change the color of brass fittings, while severe dezincification can lead to leaks.

PEX Tubing

PEX tubing, made from cross-linked polyethylene, was created to offer a more flexible alternative to metal pipes. It was designed to withstand high water pressure and can be found in the walls, ceilings, basements, and crawlspaces of residential and commercial buildings.

 

Common Failure Mode Found During Product Testing:

1

Longitudinal Fracture
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PEX tubing sometimes sustains longitudinal fractures due to oxidative degradation caused by chlorides present in the water supply. Chlorides have been used by municipal water companies to disinfect the water supply for many years. The fractures produced by this exposure can lead to leaks that may start small but grow over time.

Water Valves

Water valves control the flow of water to appliances within a home, so failure in these components can cause significant damage.

 

Common Failure Modes Found During Product Testing:

1

Rubber Component Degradation

2

Improper Valve Assembly

Explore How Freeze Damage Can Affect Valves, Too:

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The rubber components within valves can degrade prematurely as a reaction to chloride in cleaning agents or the water supply. This failure can result in an intermittent leak and potentially cause appliance overflow.

Water Valves

Water valves control the flow of water to appliances within a home, so failure in these components can cause significant damage.

 

Common Failure Modes Found During Product Testing:

1

Rubber Component Degradation

2

Improper Valve Assembly

Explore How Freeze Damage Can Affect Valves, Too:

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Valves can fail if they are insufficiently tightened during manufacturing.

Water Filters

Many residential policyholders have refrigerator water filters, and these components can sometimes fail and cause water losses.

 

Common Failure Mode Found During Product Testing:

1

Fractures Due to Freezing
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Refrigerator water filters are often subject to environmental conditions inside the appliance. If the refrigerator’s thermistor or control system is faulty, the filter may freeze and fracture as a result.

Faucets

Many different types of faucet failures that can occur throughout a home have the potential to be traced back to manufacturer’s defects or installation errors.

 

Common Failure Modes Found During Product Testing:

1

Material Deficiency

2

Insufficient Tightening of a Compression Sleeve
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Stress Corrosion Cracking (SCC) can cause brass components within a faucet to fracture. Brass components can also cause faucet failure via dezincification, or a process by which zinc is leeched away from an alloy while copper remains. Dezincification can cause damage ranging from discoloration to leaks.

Faucets

Many different types of faucet failures that can occur throughout a home have the potential to be traced back to manufacturer’s defects or installation errors.

 

Common Failure Modes Found During Product Testing:

1

Material Deficiency

2

Insufficient Tightening of a Compression Sleeve
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Plastic compression sleeves are often used for water-tight connections. When properly installed, they provide a long-lasting seal. However, installers must tighten them with the specified number of turns. Insufficient tightening can cause water loss years after installation.

Toilets

Toilets are made from vitreous china – a glazing method that makes the porcelain sleek. Unfortunately, this material can sometimes fracture due to several causes.

 

Common Failure Modes Found During Product Testing:

1

Delayed Thermal Failure

2

Overtightening Bolts

3

Impact or Shipping Damage

4

Bolt Corrosion Failure
Find Out More: Common Toilet and Bathroom Plumbing Failures
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This is the formal term for improper curing that can cause ceramic toilets to spontaneously fracture 1-10 years after they are installed in a home. Delayed thermal failure is essentially a manufacturing defect that reduces the ceramic’s ability to withstand the cooler temperature inside the tank.

Toilets

Toilets are made from vitreous china – a glazing method that makes the porcelain sleek. Unfortunately, this material can sometimes fracture due to several causes.

 

Common Failure Modes Found During Product Testing:

1

Delayed Thermal Failure

2

Overtightening Bolts

3

Impact or Shipping Damage

4

Bolt Corrosion Failure
Find Out More: Common Toilet and Bathroom Plumbing Failures
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While manufacturers often include bolt-tightening guidelines with their toilets, policyholders or contractors may overtighten toilet bolts in an effort to stop a leak. This overtightening can produce radial fractures at the bolt hole.

Toilets

Toilets are made from vitreous china – a glazing method that makes the porcelain sleek. Unfortunately, this material can sometimes fracture due to several causes.

 

Common Failure Modes Found During Product Testing:

1

Delayed Thermal Failure

2

Overtightening Bolts

3

Impact or Shipping Damage

4

Bolt Corrosion Failure
Find Out More: Common Toilet and Bathroom Plumbing Failures
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These damages often start at a chipped section, marking the impact point from which cracks spread outward.

Toilets

Toilets are made from vitreous china – a glazing method that makes the porcelain sleek. Unfortunately, this material can sometimes fracture due to several causes.

 

Common Failure Modes Found During Product Testing:

1

Delayed Thermal Failure

2

Overtightening Bolts

3

Impact or Shipping Damage

4

Bolt Corrosion Failure
Find Out More: Common Toilet and Bathroom Plumbing Failures
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Chloride in water or cleaning products can cause high zinc brass toilet tank bolts and rubber washers to corrode over time, sometimes leading to leaks.

Dishwashers

Dishwashers are one of the most common appliances that fail due to manufacturer defects or installation errors and can cause water loss.

 

Common Failure Modes Found During Product Testing:

1

Mechanical Shaft Seal Leak

2

Armature Guide Tube Degradation

3

Heating Element Hot Spots

4

Heating Element Warpage
Learn About More Dishwasher Component Failures
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This is an internal seal failure that can be caused by debris within the appliance or degradation of the seal’s rubber boot. Fracture or melting of this boot can also lead to the same failure.

Dishwashers

Dishwashers are one of the most common appliances that fail due to manufacturer defects or installation errors and can cause water loss.

 

Common Failure Modes Found During Product Testing:

1

Mechanical Shaft Seal Leak

2

Armature Guide Tube Degradation

3

Heating Element Hot Spots

4

Heating Element Warpage
Learn About More Dishwasher Component Failures
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Plastics used in the armature guide tube of some dishwashers are susceptible to chemical attacks by chlorides in the water supply. These attacks cause degradation and fractures in the plastic and can lead to leaks from the appliance’s exterior until the water supply is shut off.

Dishwashers

Dishwashers are one of the most common appliances that fail due to manufacturer defects or installation errors and can cause water loss.

 

Common Failure Modes Found During Product Testing:

1

Mechanical Shaft Seal Leak

2

Armature Guide Tube Degradation

3

Heating Element Hot Spots

4

Heating Element Warpage
Learn About More Dishwasher Component Failures
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The heating element sits at the bottom of the inside of a dishwasher and heats to wash and dry dishes. However, localized hot spots in the heating element can cause isolated thermal degradation of the plastic.

Dishwashers

Dishwashers are one of the most common appliances that fail due to manufacturer defects or installation errors and can cause water loss.

 

Common Failure Modes Found During Product Testing:

1

Mechanical Shaft Seal Leak

2

Armature Guide Tube Degradation

3

Heating Element Hot Spots

4

Heating Element Warpage
Learn About More Dishwasher Component Failures
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When water enters a dishwasher, it wets only a small section of the heating element. But if an improper cycle sequence occurs, the heating element can be partially wetted while it is hot or energized, causing it to warp.

Washing Machines

Failures in washing machines can result in significant water damage to both the appliance itself and nearby property.

 

Common Failure Mode Found During Product Testing:

1

Washer Supply Hose Fitting Corrosion
Listen to The Savvy Adjuster Podcast Episode: Plumbing Losses and Subrogation: 
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A thermistor measures the temperature within a washing machine and is connected to an electrical circuit. When the housing around a thermistor is made from poor molding, stray direct current can travel through residual water within the fitting to the machine’s grounded water hose fitting. The presence of this stray current accelerates the corrosion of the fitting connected to the washer.

Water Heaters

A variety of water heater types are used in homes, including tankless, gas, and electric. Sometimes when they fail and create water loss, it may be due to a manufacturer’s defect or installation error.

 

Common Failure Modes Found During Product Testing:

1

Internal Coating Failure

2

Drain Valve Seal Failure
Get Your Adjusters’ Water Heater Cheat Sheet
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The coating inside of a water heater is used as a protective shield against steel shell corrosion. A faulty internal coating can cause a water heater to fail prematurely.

Water Heaters

A variety of water heater types are used in homes, including tankless, gas, and electric. Sometimes when they fail and create water loss, it may be due to a manufacturer’s defect or installation error.

 

Common Failure Modes Found During Product Testing:

1

Internal Coating Failure

2

Drain Valve Seal Failure
Get Your Adjusters’ Water Heater Cheat Sheet
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This failure is caused by incompatible materials interacting and/or improper component processing and typically occurs soon after initial use. The result is a leak from the valve outlet that has the potential to cause water damage.

About CTL

Component Testing Laboratories (CTL), a part of Alpine Intel’s suite of services, includes two of the highest-volume forensic engineering facilities in the U.S. designed specifically to address your property subrogation needs. Our Professional Engineers stay up to date on trending plumbing and appliance failure modes and deliver insights you can depend on to make subrogation decisions.

Simplifying Your Product Failure Considerations

­­While it’s helpful to have a basic understanding of the failures described above, you don’t need to remember the details to look for subrogation potential in the field.

 

That’s why we created this checklist. Use it to help you, your peers, and your carrier know when to engage product failure experts and explore subrogation.

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