white van

Jetters – Getting the Right Pressure and Flow

As many of you know, water is a powerful cleaning tool. Pressure cleans off debris, flow clears it away. Simple, right? Well, yes, but when you’re choosing a jetter, there’s a delicate balance between these two elements to make sure that you’re getting the right tool for the job you’re doing, without spending too much or overestimating what the machine can do. So, here’s a guide to give you some food for thought…

What is the key component of a Jetter?

Well that’s simple – the pump. Takes on water and sends it down the hose under pressure. So you have the flow (amount of water it can take compared to the time it takes for that water to be passed through the hose) and pressure (the pressure that the water comes out of the hose). Each pump (and therefore jetter) will only put out a certain pressure and flow. Something to look for is the measurement of the jetter pressure and flow, and whether it says that it can do both at the same time. You are looking, for example for 3,000PSI AND 18 Gallons per min, not just 3,000PSI/18 Gallons per min. If you see this, you need to make sure that you are certain that the machine can provide both at the same time, or you could be caught out.

Pressure

High pressure is used to clean debris off, the first part of the jetting process. How much pressure to look for in a jetter? Well, it really depends on a lot of things – pipe size, nature of clog/business you’re doing and the nozzle or end you’re using. If you’re cleaning an 8 inch pipe, 3,000PSI may do the job well. However, if you try and achieve the same outcome in a 12 inch pipe, you’re further away from the edges, and the pressure may not be quite enough to completely remove debris from the sides of the pipe. Similarly, a 3,000PSI jetter may risk dislodging the internal structure of the pipe if you set it to work in a 4inch pipe. The question is really about what the general size of pipe you work on is. Where is the majority of you’re work?

Play into this the cost of purchasing a jetter. If the cost of buying a 4,000PSI jetter is two thirds more than the cost of a 3,000PSI jetter, and the big pipe work only makes up 20% of your business, is the additional cost of the jetter worth the investment, or would it be more cost effective to contract out this additional work? There isn’t a right or wrong answer here – it’s really based on what the majority of your work is. So, think about the sizes of the pipes you clean, and also about whether you want to clean all of them or just the core business. When it comes to pressure, bigger really isn’t always better.

Flow

So, most jetters fall into one of three categories - mini-jetters (5 gallons per minute (GPM) or less), jetters (5 to 30 GPM) and flushers (30 GPM or more).

There are two types of jetters – electric and motor.

Electric – limited by supply at the job site and 1.5 HP mode will provide small GPM rates (between 1.5 – 2.25). There is a 2 HP version, but be aware that this is a two-person job to move around. Mostly suitable for small household cleaning tasks and possibly a four-inch lateral in the right circumstances. Anything more substantial may also require a bigger machine. 1,500 PSI would sort out the debris, but the 2.25 GPM may take some time to completely clean the line, and may not do all of it at all.

A gas engine mini-jetter increases both the pressure and flow. You’re looking at the region that most of the industry sits at – around 3,000 PSI with 4 GPM. You can get up to 5.5 GSM or even more with a small water tank, but these should be approached with caution as you have to ‘feed’ the jetter with water, and if this is continuously with lower flow than the jetter is designed for, wear can occur.

Here are some typical flows and the sizes of pipes they would typically be suitable for:

MOTORGPM (FLOW)PIPE SIZE
1.5 HP electric 1.5 - 2.25 up to 4 inches
13 HP gasoline4 up to 6 inches
19 HP gasoline 12 3" to 12"
27 HP gasoline 12 3" to 12"
40 HP gasoline 12 3" to 15"
83 HP gasoline 18 3" to 24"
83 HP gasoline 35 4" to 36"
2021-07-06 - Jason