A first-time buyer of a sewer jetter should determine the amount of job calls and how often he plans to use it. An electric jetter will work on small lines such as sinks and shower drains and a gasoline jetter on any drain.
Electric sewer jetting machines used by plumbers run at about 2 gallons per minute at 1700 PSI.
Here’s what you need to know:
- It takes flow to move mass and it takes PSI to cut mass;
- Light sludge can be cleaned up with low GPM and PSI;
- Hard clogged sewer can be removed with low GPM and high PSI;
- Heavy clogged sewer drain debris needs high GPM and lower PSI;
- Roots in sewer lines need medium GPM with 3500 to 4000 PSI.
Use these calculations to determine the right equipment setup:
- Gasoline: PSI X GPM divided by 1,100
- Diesel: PSI X GPM divided by 1,250
- Electric: PSI X GPM divided by 1,460
Calculate the results to determine the right horsepower to run a pump at the required GPM and PSI.
It starts with a budget
How much do I expect to bill per month in jetting services? What would be a reasonable monthly payment? Can I carry the cost of payments during low sales? What size jetting machine is right for my business needs and does that fit into my budget?
Sewer jetter operating time?
Buying the right jetting machine to fit the operating time and level of use or abuse will determine whether whether you can keep the machine operational with very little downtime. Your downtime can negatively affect your clients' satisfaction level if the job isn’t finished on time.
Diesel versus gas jetter?
Gas engines are suitable for sewer drain cleaning because of the continuous on and off operations. They have lower output units, are more affordable and are ideal for start up operations. A gas sewer jetter, depending on options, can cost between $10,000 and $30,000. Gas engines start easier in cold weather and dealer services are more readily accessible.
Diesel engines can run continuously with high torque and even higher outputs. Consequently they are more expensive ranging between $25,000 and $75,000.
Hot or cold water jetter?
A cold water jetter is less expensive. However they are limited in their application given their difficulty in cleaning grime and grease.
A hot water jetter is more expensive due to the onboard heating system however they are very effective in heavy duty cleaning applications. Typically a hot water jetter cleans twice the amount of surface as a cold water jetter.
Which water spray nozzle to use?
Sewer nozzles come in a large variety of designs and can accelerate productivity under the right conditions.
Proper Nozzle Selection In Sewer Cleaning
What size of transport lines?
Depending on the job type, selecting the right combination of length of hose versus the hose diameter will determine the hose friction loss and the flow rates.
Water jetter productivity
For optimal performance the sewer jetter must have these elements for high productivity:
- A trained operator;
- Correct water spray nozzle;
- Jetting machine fit to job size;
- Jetter hose size and length.
After sales service
Ideally components should be nonproprietary, in other words, readily available at nearby dealers that provide water jetter parts and service.
Warranties vary from manufacturer to manufacturer and doing your due diligence on locating service centers in case of breakdowns will make the difference between a profit or loss for your business.
The US sanitary sewer collection system has a total replacement value estimated at $1 to $2 trillion. Continuous and effective management, maintenance and operation are essential to keeping system capacity and performance to extend the life of the sewer system.
Sewer pipe cleaning with a sewer jetter mounted on a vacuum tank truck should be done to clear debris and enable proper access and clear visibility for sewer line inspection. An effective sewer cleanout prevents blockages and prepares the pipe for sewer inspection cameras.
Blockages in gravity sewers are caused by poor design, poor construction, structural defect, accumulation of material, or roots. Protruding traps can catch debris causing further buildup of solids that stop the sewer flow. Sewer flow less than one to 2 ft./s leads to solids and gripped accumulation and potential blockages.
Pipeline manufacturers provide guidelines for using sewer jetter nozzles assemblies with non-abrasive caster wheels or skids positioned to prevent the assembly from contacting the pipeline. They recommend to:
- Limit water spray nozzle pressure to 2500 pounds per square inch and a maximum of 80 gallons per minute.
- Keeping sewer nozzles a minimum of 2 inches from the pipe surface.
- Maintaining fixed sewer nozzles no greater than a 30° angle of incidence to the pipe wall and rotational or spinner nozzles at no more than a 90° angle of incidence.
- Keeping the sewer jetter nozzle assembly moving continuously, ensuring that 30° nozzles remain stationary no longer than 60 seconds
Sewer pipe cleaning crews are advised to use smooth sewer hoses to facilitate movement across pipe joints to avoid damaging pipelining and to abstain from root cutters, saws or chain scraper nozzles.
Sewer jetter operators are encouraged to follow the “Jetter Code of Practice” published by NASSCO. This quick reference manual provides safe use of a sewer jetting machine, sewer nozzles and guidance on sewer pipe cleaning operations.
Detailed record-keeping by sewer jetter operators with background information on blockages help develop a preventative maintenance sewer pipe cleaning schedule. For example: Sewers serving restaurants require more frequent cleaning due to grease blockages.
Profitable sewer cleaning companies have one thing in common: they know how to optimize the sewer cleaning service by matching the sewer cleanout job with the right sewer jetter.