Sizing

Like the cable machines covered in the last issue, using a big enough water jetter for the job is critical. Employees with Bruce Maly Plumbing & Drains, Peterborough, Ont., found themselves continuously blowing pump seals on one machine, perhaps as a result of pushing it too hard. That resulted in an upgrade to a bigger jetter, says Maly. The operator must also use the largest hose that will fit in the line and still go around the bends. Typically, a 1/8 hose (inside diameter) would be used for 1-1/2 to two-inch lines, a ? hose for two to four-inch lines and a 3/8 i.d. hose would be used in four to eight-inch lines. Choosing the right size of machine may not be easy. The electric machines have proven more than adequate for many residential contractors, reported Chuck Stephens, director of service and training for Ridgid, Elyria, Ohio. They are light and take up little space in the truck. However, they are limited to about 1,500 psi or two gallons per minute. Thats about as high as you can go without popping circuit breakers, said Silverman. This makes them marginal for cleaning a four-inch lateral. A machine that can pump 3000 psi/4 gpm will do a better job, but move the contractor into the realm of gas machines that, obviously, cannot be operated indoors. A remote reel and shutoff is required. The operator can leave that 3,000 psi unit running outside all day and can take the hose inside the basement with a remote foot-valve and operate the hose and do the drain cleaning with the pressure and flow that he desires & remarked Stephens. The same machine can be used for smaller jobs by reducing the size of the hose along with flow and pressure. You can also idle down the engine, which will have the same effect, said Stephens. The larger gas machines allow the contractor to expand into the commercial market with the ability to clean grease traps, shopping mall, institutional and apartment drains. The higher the pressure and the higher the flow rate, the more you will be pleased with the performance of your machine, added Silverman.

Operation and maintenance

If a water jet machine is maintained regularly, it should continue to offer like-new performance for many years, said Stephens. Its all about pressure. The pumps and other components are fully rebuildable. Many features from the larger machines  filters, backflow preventers, thermal relief valves  have been added to the smaller machines. All of these things add to the reliability of the machine, noted Silverman. Pump seals wear out over time, as do nozzles. Both problems result in a pressure drop, as do air or water leaks in the fittings. The holes in the nozzles require regular cleaning with correctly sized wire cleaners. Filters and/or filter screens must be cleaned. Silverman suggests three things for reliable operation: First, the operator must ensure that theres enough water. A lack of water will cause cavitation and damage the pump. I have actually seen a machine suck a hose flat because it couldnt get enough water, he added. The easiest way to do this is to take a standard two-gallon bucket and time how long it takes to fill. If it takes a minute, thats only two gallons per minute  not enough for most gas machines. Trailer mounted machines may require as much as 12 gpm and therefore include a storage tank. Hot water can damage the pump. Theres a common misconception that hot water is better for clearing grease. The problem, besides possibly damaging the pump seals, is that the grease will congeal further down the line and cause another blockage, says Silverman. If you break up the grease in chunks with cold water, it will flow down the line and be gone. The third danger is allowing the machine to freeze by leaving it in the truck overnight in the winter. It should be either kept inside or filled with anti-freeze when not in use, said Silverman. The biggest thing with the jetters is damage to the hoses, said Maly. Inadvertently, you come across a bad pipe where it can be scraped or they just burst. A good quality hose will better handle the pressure and be more resistant to abrasion. His crews do everything they can to minimize damage. A plastic protector in the cleanout or vent stack helps. They regularly inspect the hoses for nicks or cuts and tape them up to prevent them from getting worse where the damage isnt severe. But, journeyman plumber Nathan Bonaldo admits: Sometimes we have to pull these out with a truck. A color-coded tape ten feet from the end of the hose will warn the operator, when pulling the hose back, that they are getting close to the nozzle. You can hear it coming back, but there will be instances when the jetter head is under water and that will muffle the sound, noted Maly.

Hose attachments

Manufacturers list a number of special nozzles to make jetters more versatile. Some work on a water turbine principal. One thing to keep in mind with any rotating device is that it will instantly twist the hose into knots if it gets caught up on an obstruction. Generals chain-wheel root cutting heads avoid this by operating like a weed wacker. Ridgids Root Ranger uses a narrow stream of 3,000 psi water to cut through roots, something the company demonstrates by cutting through two-by-fours. Malys crew finds their wedge, with one nozzle pointing forward and the rest to the rear, very effective for ice blockages. Some contractors add a wand kit so they can use the machine as a pressure washer to clean their truck(s). Malys employees often tape a camera head about 10 feet back from the nozzle and use the jetter to pull it up to 100 feet. A line that has been jetted offers a substantially better picture for the camera. Sometimes they use a cable machine and jetter together, particularly where a line is completely blocked and where introducing more water with a jetter will create a big mess. The blockage is cleared with a cable machine and then the line is cleaned with the jetter. At the end of the day, says Maly, manufacturer backup is key in achieving the best performance from a water jetter. There are always going to be issues. It all comes down to whether (the manufacturer) has a good representative behind the product.