Ask Vince #11 Drain vent, slow drain

Drain vent, slow drain

QUESTION: Recently, a friend had a problem with his kitchen sink drain and tried all kinds of things to clear the drain. He finally had to call a sewer service, which fixed the problem when he wasn’t home. A service representative said the problem was a clogged vent, but my friend doesn’t know how it was repaired. I live in an older home with some slow drains, and I may have the same problem. How do you clear a clogged vent?
Dick Conway via email

ANSWER: “Most homeowners, as well as the majority of drain-cleaning personnel, give no thought to a stopped-up vent system preventing a drain from working properly,” says Vince McDonald of McDonald Plumbing, Heating and Air Conditioning in Sacramento. “Although a plugged vent can interfere with the proper functioning of the drain, it rarely stops up a drain completely,” he says. “Poor waste-pipe drainage can be somewhat tolerated in a basin or bathtub, but when it comes to a washing machine drain, it can result in a flood of water onto the floor.”

“The purpose of the vent is to introduce air into the drainage system. It equalizes the pressures in the system and permits the wastewater to flow freely down the line. The vent also prevents the water in the trap, sometimes called the goose neck, from siphoning out. The trap, with its built-in water seal, prevents sewer gas from entering your home through the drainage system. When wastewater runs down a waste line, it often backs up into the venting system. As it recedes, it leaves behind residue and waste particles. Over time, the vent can become stopped up and no longer provide its important function.”

“In California, code requires all plumbing fixtures to be properly vented. The vents for all plumbing fixtures pass up through the walls and terminate through the roof. “one quick way to check your vents is to run water from a garden hose down through your vents from on top of the roof,” McDonald said. “Sometimes a drain-cleaning technician will run a machine down the vent from on top of the roof. Often, the vents of more than one plumbing fixture will be connected together before passing through the roof. Because of the nature of this repair, it would be a good idea to hire a professional drain cleaning or plumbing company,” McDonald advises.

More Information on Drain Pipe Problemsin Your Sacramento Home or Office

Drain pipe problems can have multiple causes. The drain pipe is typically made of either iron or PVC pipe. A kitchen and bathroom sink drain pipe is typically either 1-1/4 or 1-1/2 inches in diameter. For laundry facilities, the diameter is usually 2-inches and toilet drain pipes are typically three inches in diameter.

The Right Size Drain Pipe for the Job

Although it seems logical to think that larger drain pipe would provide better drainage, this is not the case. Larger pipe actually dissipates the gravitational pressure that is created as waste moves through the pipe. Likewise, drain pipe that is too small for the intended use is prone to clogging.

The Drain Trap

All drains incorporate a curved section of pipe called a trap. Drain traps are designed to hold water that forms a seal to prevent noxious sewer gases from rising through sewer lines and being emitted into your home. Traps also prevent small objects that accidentally enter the drain lines from being swept into the sewer mains. Unfortunately, the curved design of drain traps also causes them to become clogged.

Clogs that occur in trap pipes can usually be removed fairly easily. In some cases the obstruction can be cleared by dissolving or forcing the material creating the clog through the trap. Minor clogs can often be loosed with chemical drain cleaners. More stubborn clogs may require the use of a plunger or sewer snake. More severe clogs may require that the trap be removed.

The Correct Slope for Your Drain Pipe

Improper sloping is another cause of drain pipe problems. The minimum suggested slope is 1/4-inch per foot of pipe. Drain pipes that slope less than the prescribed amount are more prone to clogging.

Proper Venting

To relieve excess pressure that can build up in drain pipes, plumbing fixtures are equipped with vent pipes that connect to the home’s main vent stack that exhausts through the home’s roof or exterior walls. In rare cases, the vents can become obstructed. When this happens, pressure can build in the drain pipe and cause water and waste to drain more slowly.

Clogs in the Sewer Main

If more than one plumbing fixture is experiencing problems, the reason could be a clog in the main drain pipe. The main drain line connects all the drain pipes in your home to the sewer main. In addition to clogs created by household waste including hair, tissues, food particles and grease, the main drain pipe can become obstructed by tree roots and dirt.

Enlisting the Help of a Drain Specialist

Depending on your level of plumbing skill and the tools in your plumbing arsenal, you may choose to tackle some repairs yourself. However, for the novice plumber, this can lead to a frustrating waste of time and money.

Because of their skill and experience, a professional plumber can usually diagnose and fix virtually any drain pipe problem you may be experiencing in less time and, in many cases, for less cost than attempting the repair yourself. An added benefit is that most reputable plumbers offer guarantees on their work and can usually offer advice on how to prevent the problem from returning.

Contact McDonald Plumbing, Heating and Air Conditioning in Sacramento to Resolve Your Drain Pipe Issues

Since 1957 McDonald Plumbing, Heating Air Conditioning has been providing plumbing and heating repairs and installations to Sacramento residents and businesses, including finding and resolving drain pipe issues. We also serve Sacramento and the surrounding communities with a full line of plumbing, heating and air conditioning repairs such as tankless and regular water heater installation and repair, air conditioning installation and repair, home energy audits, home comfort systems, sewer and drain cleaning, sewer and water line repair and repair of slab leaks.

Sacramento, CA

Sacramento is the capital city of the U.S. state of California and the seat of government of Sacramento County. It is at the confluence of the Sacramento River and the American River in the northern portion of California’s expansive Central Valley. With an estimated 2011 population of 477,891, it is the sixth-largest city in California and the 35th largest city in the United States. Sacramento is the core cultural and economic center of the Sacramento metropolitan area which includes seven counties with an estimated 2009 population of 2,527,123. Its metropolitan area is the fourth largest in California after the Greater Los Angeles Area, San Francisco Bay Area, and the San Diego metropolitan area, as well as the 27th largest in the United States. In 2002, the Civil Rights Project at Harvard University conducted for TIME magazine named Sacramento “America’s Most Diverse City.


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