Why Filtration is Critical in Weed Control and Pest Control Sprayers

Why Filtration is Critical in Weed Control and Pest Control Sprayers

Posted by Andrew Greess on Dec 17, 2018

Check the filter. Check the filter. Check the filter!

I know that seems redundant, but we know it bears repeating. And then we repeat it again. Because with all our experience in our shop we know that as much as technicians say “I checked the filter!” and “Yup, boss, cleaned the filter” ...they don’t! We can prove that with many examples of filters being anything less than cleaned. If your technicians can’t open the filter, they can’t clean it.

Your spray equipment technicians can’t clean the filter when the tank is full if there is no shut off valve. It benefits the company to teach its technicians  the importance of the filter: how it works, why it needs to be cleaned and that it’s not okay to just skip over it. It is there to filter gunk and debris from reaching the pump. When it gets clogged it will prevent water from reaching the pump and the engine will seize up, much like a car engine and it’s need for oil. It’s also important not to ignore cracks or swollen o-rings. If the o-ring doesn’t fit it won’t prevent chemical from spraying out all over. Spraying chemical isn't safe and it’s not cost effective.

All of this comes back to the basics of: design and care. Without good design proper maintenance cannot be performed. When maintenance isn’t completed there will be lost revenue due to repairs. It is worth your time and money to  keep your equipment in proper working order.

Be sure to check out our next video on Cleaning out the Debris! 

Andrew Greess: Now I want to talk about filtration, and filtration is really important. I would say at least half the problems we see in our repair shop have to do with the filter. It's just amazing. In fact, when a technician comes to our shop and tells us he or she has a problem and wants a repair, we don't even listen.

We do listen to what they say, but we check the filter first because, so many times, the filter is the cause of the problem. When I say filtration, I mean the design of the filtration, I mean the operation of the filtration or the filter, and the maintenance, and I've got examples of each.

This is an example. Back 10 years ago, when we were still building lots of houses in Arizona, and there were lots of big termite companies doing 20 termite pre‑treats a day, a customer kept having problems with their filters getting clogged.

We always felt like these subdivisions, some of these contractors are just throwing their garbage in the plumbing lines. Then when the termite guys show up to fill their truck, they get rocks, debris, and garbage in their sprayer, in their filter. What we had to do was, we ended up putting three filters on the truck.

The first filter was on the hydrant line before it even got to the tank. Then there was a filter basket in the top of the tank, and then there were two filters after the tank before the pump. The first one was really coarse and the second one was fine. The technicians' instructions were, "Check every filter before every job because they're going to get full."

My point isn't that you need this much filtration on your sprayer. My point is you need to make sure you have the right filtration on your sprayer. This is just an extreme example. You design a filtration based on your water source, the products you're applying, the equipment you're using, and your technicians.

If you're doing pest control or weed control and just using municipal water, one filter's probably fine. The broader point is, make sure it's the right filtration and make sure it's designed well. Remember this photo? This is not good design.

I want my technician to check the filter every day, and he or she is not going to be checking this filter. It's too hard to get to. Then it's also, the problem, there's no shut‑off valve, so they can't check it if the tank is full. That's bad design.

Here's how we do it. I showed you this picture. It's the shut‑off valve in front of the filter. Even when the tank is full, you can check the filter, and you have a lot less problems. If your technicians will check the filter every day, so many problems go away.

Now for some fun. Are your technicians checking the filter? Every company owner and every company manager says, "Yeah, my technicians are checking the filter." I can't even tell you the number of times we get paid to clean someone's filter, and, I actually have this. This is a filter that was brought in and...We got pest guys here or weed guys or...? What do we got?

Pest guys? Weed guys? The weed guys know the yellow stuff is pre‑emergent. I'll let you come up and look at this later, but this is rock solid. This full in the sprayer, which means there was never any screen in this because it won't fit. Every company we talked to says, "Oh yeah, my guys check the filter. No problem." Well, someone wasn't checking the filter.

The other thing about this is, if your filter's this bad, think about what your fittings, your spray tips, your hoses, and your pump...Think about what everything else is doing. This got to weigh two pounds right here. It's like a solid rock. You guys can come look at that later. Here's another one.

A technician comes in and says, "My pump doesn't work, and by the way, I haven't checked my filter in a month." "Why haven't you check your filter in a month?" "Well, it's too hard to open." We took a pair of channel locks. It took us three seconds to open with channel locks, and this is what we found. Again, you can tell that's pre‑emergent.

This company was using a diaphragm pump. It was a total loss because the tech had run this for so long, the pump was starved for water. It'll work for a little while without any water, but after a while, it's like running your car without oil. It's going to get too hot, and it's going to fry it. This cost the company a brand‑new pump.

The issue here, clearly the guy should have checked this filter, but the biggest issue isn't that he didn't check his filter. The biggest issue is that the tech did not tell his boss, "Hey, boss, I can't check the filter. What should I do?" Then the boss would have said, "Let me give you a pair of channel locks to check the filter." This cost them $1,000 because the tech didn't say anything.

You call the owner of a company and tell them that, man, you are not talking to happy camper. Here's another one. This was a pest control company, and the owner swore that his techs were checking the filter. I go, "I'm looking right at it. Your techs are not checking the filter. You're paying us to check the filter. It doesn't make any sense."

He swore up and down, "Oh, my techs checked the filter." I guess not, but we see this all the time. That's probably ‑‑ what do you think? ‑‑ couple of weeks, a couple months' worth of junk in that filter there?

Here's another one. This is a weed control truck. We dumped the contents of the filter out on the bed. The white stuff is dried chemical, and the big stuff is rubber gloves. The only thing we could think...You can see they're green because they put dye in the weed stuff.

The only thing we could think of is the tech took off his gloves and said, "I need to throw these away. Oh, there's a hole in the top of the tank. That must be for trash." The tech throws the garbage in the top of the tank because "it's a hole. Might as well throw my trash in there." The filter did do a good job. It did stop this from getting to the pump and destroying the pump.

The weirdest things we've ever found in filters, we found fish. A guy filled up from the canal once, and he got all these fish that clogged his filter and destroyed his pump. Then we once found a pair of men's underwear. The most common thing you find is the, when the chemical bottles have a little paper or cardboard thing in the cap. We find that all the time. Then soda cans and trash.

Some of you guys use B&Gs. The bottom one is what the filter of a B&G is supposed to look like. The top one is what this one looked like. Again, this filter wasn't checked for probably years. That's just going to wreak havoc on your B&G, certainly on your B&G tip, and on your ability to do your job. Checking and cleaning your filter is absolutely critical. It'll eliminate a lot of your problems.

Here's another one. Maintenance. Eventually ‑‑ you can't keep checking your filter ‑‑ you got to change it. I'm very proud to say, this is one of my proud...I did not make this up. What we think happened here was the tech pulled a Honda pull cord and it broke, so he threw it in the tank because, "Where else...I don't want to put in the truck. I might as well throw in the tank."

This is what we saw. Again, the tech says, "My pump doesn't work. We just checked the filter." This is what we found. Of course, there was no screen in it because the screen can't fit when you have this.

This was so good. I called the owner of the company and said, "Hey, I'll be happy to put a new filter on there if I could have the old one." "Oh, sure." We call this our technician hall of shame. Aside from the fact he's throwing trash in the tank, obviously no one checked this filter. You would think that would be a problem.

You don't have to be a technical genius to figure out this is a problem. I'll move that up there. I love that one. That's my favorite. What else we got? Here's another one. Tech comes in says, "My pump doesn't work." We check the filter. What had happened was, it's hard to see, but there's a crack in this filter.

What the tech did was he put a piece of duct tape on the inside of the filter to try to stop the leak. I give him a couple of points for trying to do the right thing and trying to fix it and get through the day, but duct tape is not going to fix a cracked filter.

If you're going to put duct tape on a filter, you really should put it on the outside, so the pump sucks the tape towards the crack not away from the crack. This guy really needed some more training. He's got a good attitude. He just has no understanding of how this works. Probably, when your filter is that bad, don't mess with duct tape. Just come get a new filter.

Think about it. Any problem you have in Phoenix, you're going to have to stop what you're doing and drive back to a repair shop like ours, or your own shop, or somewhere. In Phoenix traffic, you're losing a couple hours probably. Half‑an‑hour each way plus repair time.

I'm with you to try to get through the day, but, something like that, I think the owner of this company needs to do a better job at training his technicians on how stuff works. Here's another one. Technician says, "My pump isn't pumping." We go look at it, and the filter's all dirty. It's got green, and blue, and yellow all over it.

The weed guys will recognize this as pre‑emergent with dye in it. It's a little hard to see, but that black ring is the gasket or the O‑ring that goes in the filter. What happens is, the chemicals ‑‑ particularly herbicides ‑‑ swell the gasket. The tech couldn't get the gasket back inside the filter, so he just put it on the outside, and it don't work.

Again, he was trying to do the right thing, but he didn't understand how this works. If you're the boss or the owner, you got to train your guys a little better than this. I don't know how much chemical spilled all over the truck, but this guy should have just got this taken care of right.

If you missed any of the videos in this series, catch up on them here:

Experience Pays: Top 10 Avoidable Spray Equipment Problems And Ways To Avoid Them

Choosing the Right Spray Equipment Engines, Backpacks, Pumps and Trailers

Spray Fittings and Tanks - The Right Small Spray Equipment Components Matter Too

Oh The Hose Reel Problems We’ve Seen!

Cut Out Design Flaws and Down Time with Better Spray Equipment Design

Common Sense Missing in Some Backpack Sprayers

Avoid Problems By Consulting Experts in Their Field

Bad Design = More Work And Money in Repairs

Need Easy Access to Spray Equipment Filters

Bad Spray Equipment Design Leads to Tank and Pump Troubles

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