Six Things To Consider Before Using A Water Jet
By Marty Silverman
Grease, sludge, sand and ice stoppages can present a signiﬁcant challenge for many cable drain cleaners, but water jetter machines are designed to slice right through these difﬁcult blockages.
Whether electric or gas-powered, compact mini-jets for clearing inside sink lines or big trailer units that can scour large mains, water jets unleash high-pressure water streams that pulverize those clogs, ﬂushing the debris down the drainage line. An excellent option to service restaurant, hotel, hospital and factory clients, or for customers on septic systems, they are also great for schools, sports arenas, care facilities and shopping centres.
Water jets can clear clogs that many cable drain cleaners can’t, and with proper maintenance they can prove reliable business assets, but there are a few considerations to observe before ﬁring up your water jet to battle hidden clogs.
1: The Blockage Type
Water jets work best on so-called “soft” stoppages. They’re not the preferred tools on, say, tree roots – which really require cable-type drain cleaners. If you can’t identify the type of clog, use an inspection camera to take a look. If you still can’t I.D. the problem, consider how the line is used. That’s where professional judgment proves vital.
If the drain in question deals with food service, for instance, grease is probably the culprit. In fact, clogs in drains leading from restaurants, multi-family dwellings, and institutions with food preparation facilities are likely comprised of grease.
The same goes for clogged conduits in factories and industrial facilities that ﬂush lubricants, solvents, or various organic materials down drains. But sand can also pose problems in certain areas. In frigid weather, ice could prove the culprit. And if it’s a construction site, mud can trigger troubles.
2: Don’t Get Stuck
The ability to vibrate the hose while it is in use is a prescription for maximum equipment performance, and minimal job-site headaches.
When connecting a hydraulic hose and rear facing nozzle to a water jet, and then shoving it down a drain, the hose might get stuck in the pipe. If that happens, you’ll need an excavator to remove it! Vibration helps to break up surface friction between the hose and pipe so the nozzle doesn’t get stuck in the line.
3: The Right Size Hose
A common way of getting the hose stuck in the pipe is by using a wrong size, and this is surprisingly easy to do. When working with high-pressure water, use the largest hose that ﬁts down the drain.
Hoses with a larger inside diameter (ID) don’t have as much pressure loss from water friction over distances. For instance, the friction loss in 1/4” ID hose with four gallons-perminute (gpm) of ﬂow is 360 psi for every hundred feet. If you use a 3/8” ID hose for the same situation and distance, the corresponding pressure loss falls to just 50 psi.
In short: the larger the hose, the greater the nozzle pressure. And the greater the nozzle pressure, the easier and faster the job. However, remember that a balance between hose size and ﬂexibility also exists.
Generally speaking, bigger, thicker hoses tend to be less ﬂexible. Smaller, thinner hoses tend to be more ﬂexible. Regardless, if you use a larger hose in a small pipe to reap the beneﬁts of higher nozzle pressure, exercise caution. Do your homework and leverage your experience to coax the most from your water jet equipment.
4: Do You Have Sufficient Water?
Since high-pressure water is the tool actually powering water jet drain cleaning work, make sure you have enough of it! If you use a large water jet with a holding tank – trailer-mounted equipment, for instance – simply ensure that the tank doesn’t run dry.
Fortunately, most of today’s units sport an automatic shut-off feature that keeps you from making this mistake. However, if you are using equipment that draws water from a garden hose or similar supply, more attention is required.
Most North American municipal and well water systems deliver roughly ﬁve to six gallons per minute of ﬂow. If you are not sure what the ﬂow is from the hose you are using, measure how much time it takes to ﬁll a common two-gallon bucket and do a quick calculation.
Failing to watch your water could cause you to accidentally starve the pump of water, causing cavitation. Cavitation is the second most popular way to kill a pump, so watch your water usage!
5: Keep Moving The Hose
Working the hose back and forth remains the preferred technique for jetting a line. Push the hose two feet forward, then pull it back one foot – and repeat this procedure for the rest of the job.
Maximum cleaning action occurs when retracting the hose – not as it goes in. As you pull back, the angle of water ﬂow exiting the nozzle scours the pipe sides. This magniﬁes the cleaning efﬁciency for a better job in less time.
Additionally, turbulence created by high-pressure water ﬂow in pipes can produce vortices behind the nozzle. If the hose remains stationary for any length of time, sand, loose dirt, grease or sludge can collect behind the nozzle, creating a plug that traps your hose in the pipe. This is not good!
6: Don’t Freeze Up
Freezing statistically remains the number 1 way to kill your pump. It can be surprisingly difﬁcult to keep your pump from freezing during frigid weather. Damage can occur before, during or after jobs, and the cold can affect hoses as well. If your unit has an antifreeze tank – as on large gas-powered or trailer-mounted equipment – use it when temperatures even start to approach the freezing mark.
If your unit does not have this feature, use a short hose and funnel to introduce antifreeze into the pump to prevent freezing. For the hoses, remove the nozzle and use an air compressor to blow water out of the hose before driving. You don’t want ice to form as you are en route to or from a jobsite.
It is also best to limit the time a water jet sits without water ﬂowing through the pump. Turn the unit on frequently, running water through the bypass system to to keep it warm.
Marty Silverman is the VP of marketing for General Pipe Cleaners.