Corroded Pex Fittings: The Ultimate Guide to Understanding and Fixing the Issue
What To Know
- Chlorine, a common disinfectant used in municipal water supplies, can react with PEX fittings, causing a chemical reaction that leads to corrosion.
- Different metals, when in contact with each other in the presence of an electrolyte (water), form a galvanic cell, causing the less noble metal to corrode.
- If the water supply has high acidity or alkalinity, install a water treatment system to neutralize the pH levels and reduce corrosion risk.
PEX (cross-linked polyethylene) fittings are widely used in plumbing systems due to their flexibility, durability, and resistance to corrosion. However, under certain circumstances, these fittings can succumb to the insidious effects of corrosion, leading to costly repairs and potential health hazards. Understanding the underlying causes of PEX fitting corrosion is paramount to preventing these detrimental occurrences.
Causes of PEX Fitting Corrosion
1. Chlorine Exposure
Chlorine, a common disinfectant used in municipal water supplies, can react with PEX fittings, causing a chemical reaction that leads to corrosion. The presence of chlorine in water can accelerate the degradation process, especially in higher concentrations.
2. Oxygen Permeability
Unlike metal pipes, PEX is slightly permeable to oxygen, which can diffuse through the fitting walls and react with the metal components inside. This oxidation process can weaken the fitting and lead to corrosion.
3. Improper Installation
Incorrect installation practices, such as overtightening fittings, can damage the fitting and create microscopic cracks that allow water and oxygen to penetrate, promoting corrosion.
4. Incompatible Fittings
Mixing PEX fittings from different manufacturers or using non-PEX fittings can lead to galvanic corrosion. Different metals, when in contact with each other in the presence of an electrolyte (water), form a galvanic cell, causing the less noble metal to corrode.
5. Aggressive Water Conditions
Water with a high acidity or alkalinity can be corrosive to PEX fittings. These extreme pH levels can damage the protective layer on the fitting and expose the metal to corrosion.
6. Bacterial Growth
Bacteria can thrive in the moist environment of plumbing systems, producing corrosive byproducts that can attack PEX fittings. This is especially true in areas with high bacterial counts or inadequate water treatment.
7. Galvanic Corrosion
Galvanic corrosion occurs when dissimilar metals come into contact with each other in the presence of an electrolyte. In plumbing systems, this can happen when copper pipes are connected to PEX fittings using brass or galvanized steel components.
Consequences of PEX Fitting Corrosion
1. Leaks and Bursts
Corrosion can weaken PEX fittings, leading to leaks and even catastrophic bursts. This can cause extensive water damage and costly repairs.
2. Reduced Water Flow
Corrosion can clog or obstruct the flow of water through the fittings, reducing water pressure and affecting the efficiency of plumbing fixtures.
3. Health Hazards
Leaking or burst PEX fittings can contaminate the water supply with corrosion byproducts, which can pose health risks if ingested or inhaled.
Preventing PEX Fitting Corrosion
1. Use Chlorine-Resistant Fittings
Select PEX fittings specifically designed to resist chlorine exposure. These fittings have a protective layer or coating that helps prevent chlorine from reacting with the metal.
2. Install Fittings Correctly
Follow manufacturer guidelines for proper installation, including using the correct tools and applying the appropriate torque. Avoid overtightening fittings.
3. Use Compatible Fittings
Ensure that all PEX fittings used in the system are compatible with each other. Use fittings from the same manufacturer and avoid mixing different types of metals.
4. Treat Aggressive Water
If the water supply has high acidity or alkalinity, install a water treatment system to neutralize the pH levels and reduce corrosion risk.
5. Control Bacterial Growth
Regularly flush and disinfect plumbing systems to prevent bacterial growth and minimize the production of corrosive byproducts.
6. Use Galvanic Isolators
Install galvanic isolators between dissimilar metals in the plumbing system to prevent galvanic corrosion.
Ending Corrosion: A Proactive Approach
By understanding and addressing the causes of PEX fitting corrosion, homeowners and plumbers can proactively prevent these costly and hazardous occurrences. By implementing the recommended measures, it is possible to ensure the longevity and reliability of PEX plumbing systems for years to come.
Questions You May Have
Q: How can I tell if my PEX fittings are corroding?
A: Look for signs of rust or discoloration on the fittings. Corrosion can also cause leaks or reduced water flow.
Q: Can I repair corroded PEX fittings?
A: In most cases, corroded PEX fittings need to be replaced. Attempting to repair them may compromise the integrity of the fitting and lead to further problems.
Q: What should I do if I have corroded PEX fittings?
A: Contact a qualified plumber immediately to have the fittings replaced. Do not attempt to repair the fittings yourself as it could worsen the situation.
Q: How often should I inspect PEX fittings for corrosion?
A: Inspect fittings regularly, especially if you have a water softener or live in an area with aggressive water conditions.
Q: Can I use metal fittings with PEX tubing?
A: Yes, but it is important to use galvanized or brass fittings specifically designed for PEX. Avoid using copper fittings as they can cause galvanic corrosion.
