A recent service call to see what we could do to increase water pressure for a Brooklyn homeowner resulted in replacing an entire water service line. The cause for such an extensive repair? A previous repair not done by us!
Someone had used a cheap galvanized dresser coupling to connect the brass main control valve to the lead water service line. Connecting galvanized metal to brass or copper is a sure recipe for future disaster.
The result of connecting those dissimilar metals, of course, was galvanic corrosion. This type of corrosion occurs whenever two or more dissimilar metals (like the galvanized coupling and brass valve here) come into contact under the right environmental conditions.
“It only takes one piece of galvanized pipe in a plumbing system to ruin water pressure throughout a house.”
Unfortunately, this galvanized fitting was in direct contact with the lead water service line. Since that original repair, city code has changed and no repairs of any kind are allowed on lead water lines. Instead, the NYC DEP requires a complete replacement:
“A new service pipe must be installed where more than one-half (1/2) of an existing service pipe is in need of a repair or when any repairs are required and the existing service pipe is lead, galvanized steel or galvanized iron.”
A Brooklyn homeowner’s call to increase water pressure
A recent call to increase water pressure from a Brooklyn homeowner illustrated the importance of using approved brass fittings. A past repair on a lead water service line utilized a galvanized dresser coupling to connect form the lead water line to the brass main control valve. When dissimilar metals, such as galvanized pipe and brass, are connected together galvanic corrosion is the result.
All it takes are electrolytes in the soil or water and the ions from one of the metals will move to the other. This results in a weakened metal that will fail at some point – it is just a matter of time. Unfortunately, the weakened pipe can look fine right up until it fails. As this homeowner discovered, one of the early indicators of that possible failure is low water pressure.
It only takes one piece of galvanized pipe in a plumbing system to ruin water pressure throughout a house. In this particular case the galvanized fitting was connected directly to the lead water service line, which meant the entire line had to be replaced. In the end using an interior fitting resulted in a $4,000.00 plumbing installation in order to increase water pressure.
At the time the repair was done brass compression fittings were allowed by code. So simply using an approved brass compression fitting would not have resulted in galvanic corrosion, and a drop in water pressure. Since the time of the original repair performed at this location, the repair of lead water lines has been disallowed by NYC plumbing code altogether.
The importance of using a licensed and reputable Plumber
This repair demonstrates the importance of trusting a licensed plumber, and using approved brass fittings. If the original repair used such a fitting instead of that galvanized dresser coupling, there would have been no galvanic corrosion and no $4,000 pipe replacement in order to solve a simple water pressure problem! Inexperienced and unlicensed plumbers are prone to cut corners, and use inferior or illegal materials.