Nothing is more frustrating to a homeowner than a clogged drain during a special dinner or family holiday — or a toilet backing up because of a blockage in the outside drain line. And when she calls your company to fix the problem, she’s expecting a professional who will diagnose the problem correctly and provide the correct solution.

Plumbing & Mechanical asked manufacturers and plumbers in the drain-cleaning community for their top tips for professionals in the field.

Many tips have to do with safety and protection — for the technician and for the customer. Dave Dunbar, assistant sales manager at General Pipe Cleaners, stresses the importance of following all equipment safety instructions.

“Only use machines with a functional ground fault interrupter and undamaged electrical cord,” he says. “More contractors die because of electrocution than all other forms of jobsite accidents combined. Don’t take chances.”

Jaime Smith, owner of Mr. Rooter Plumbing of Baltimore, says protect, protect, protect — the customer’s home, your equipment and yourself. Drain cleaning can be a messy and unsanitary business, so it’s important to use protective gear and safety equipment on every job.

Roto-Rooter service plumbers agree: Via the company’s Facebook page, they advocate the use of safety gear such as a face shield and rubber gloves to protect the technician as well as the surrounding environment.

Another safety concern is forcing the cable down the drain, which can have some serious consequences. “Drain-cleaning machines all utilize spinning cables in order to clean pipe, which are long, thin springs designed to efficiently transfer torque between the motor and the spinning head,” Dunbar explains. “When used properly, they function more like drills than hammers, cutting through blockages because of their rotational torque, not the ramming effect of their forward momentum.”

 When a cable is forced down the line, the operator tends to bend and twist the cable, weakening its ability to transfer torque and increasing the odds it will kink, he adds. The result is a “cascading effect” that may cause severe injury to the technician, as well as potentially damage the equipment.

Roto-Rooter techs add that if you’re trying to force a cable through a blockage, you could be “poking at a baffle, crushed pipe or manhole area” and eventually damage the pipe or fitting, exacerbating the problem.

Mark Speranza, Electric Eel vice president of sales and marketing,  notes that proper maintenance and routine inspection of drain-cleaning equipment, including cables, will help minimize problems.

“Shorter cable lengths and multiple drums can reduce weight, improve maneuverability and reduce operator fatigue,” adds Brandon Moherman, global marketing manager of drain cleaning at RIDGID.

Selecting the right equipment

A proper diagnosis of the problem is crucial before beginning, note Roto-Rooter technicians. Ask the homeowner or building owner which drain is the problem and if any chemicals have been added to the drain.

Drain-cleaning professionals should always have a sewer camera available to inspect drain and sewer lines, Smith notes. And be aware of the jobsite conditions. Does the drain exit the property from the front or the back? What is the distance of the pipe run? “Running cable blind often leads to mistakes,” he says.

Once the problem has been diagnosed and safety precautions taken, technicians must select the best equipment for the job. “Determing the proper size equipment for the job is critical in cleaning a drain effectively,” Speranza explains. Equipment size is determined by drain diameter, length and material of the drain pipe, as well as what kind of clog it is.

Drain-cleaning professionals also need to know the difference between drum-style continuous cable machines and those with sectional cable, as each is designed to handle specific types of lines and blockages.

“To clear clogs such as tree roots and tough debris out of larger lines, a heavy-duty sectional cable drain cleaner with a cutter tool would be the best machine for the job,” Speranza says. “To clear smaller indoor drain lines, a compact drum style continuous cable unit would be a good choice.”

Cutting blades are important, too, says Roto-Rooter. An undersized blade may poke through a clog and open the drain, but it won’t clean the pipe. “For best results, use a smaller blade to get the pipe to drain, then swap blades to the ideal size to shave the roots down to the pipe walls,” techs say.

Different types of cables can be used for different needs. “Choose integral-wound cables where greater stiffness is desired and inner-core cables when greater flexibility is preferred,” Moherman says.

It’s important to keep clearing the line all the way to the end, even if you believe you’ve broken through the stoppage and the pipe is draining, Roto-Rooter techs note. There may be other “choke points” at the other end.

And make sure to run water down the drain, Dunbar says. It will make the job go faster, leave the pipe in better condition and keep your cables cleaner.

Lastly, once the job is finished, apply lubricant to the cable to protect it from chemical drain cleaners that may have been added before a professional was called.

 “The cable is one of the most expensive replacement parts on your drain-cleaning machine — protect your investment,” Dunbar adds.