Over the past few years, we’ve collected a lot of correspondence with questions touching on just about every aspect of pumping. With many new pumpers entering the industry — while others retire or move on — we tend to get a lot of repeat questions. To wrap up 2008, we’ve assembled the three most common problems and their solutions:
Tennis ball anyone?
QUESTION:
Something has screwed up my ability to pump. When I turn on the pump, the system refuses to create vacuum pressure. I’ve checked the system by disconnecting the hose and it seems to be operating just fine. What’s my problem?
ANSWER:
This is one of the most common problems and the simplest to solve. If you disconnected the hose and you’re getting plenty of suction, then obviously something is stuck in your hose. Whether it’s a T-shirt, a tennis ball or random piece of large garbage, something has plugged up your hose. If you can’t locate the blockage to remove it, try another hose and see how the system works. We think you’ll be pleasantly surprised how well your system works when you have a clear path for the air to flow.
The trap worked, the employee didn’t
QUESTION:
Yesterday, I had an employee run his route and everything was just fine. He reported that the pump was smooth, powerful, and effective. He even worked later and got some extra work done so there is less to do today. Today, however, the thing is sick. The pump doesn’t have that same power and seems to want to overheat quickly. Why is it good to go one day and sick the next?
ANSWER:
Most likely you have gotten some debris or waste in your pump. Vacuum pumps are not designed to run efficiently when they are clogged with debris. First thing to do is check your secondary moisture trap.
We’ll bet you a dollar that when your employee finished up that night, he returned to the shop, punched out and went home. What he should have done upon returning was empty the secondary moisture trap. During the course of pumping all day long, the tank filled up and debris got past the primary shutoff and made its way to the secondary. And like a good secondary moisture trap, it did its job and trapped the stuff before it escaped to the pump.
But when the pump was started the next day, a lot of the debris that had been caught by the secondary the day before now got loose and rocketed directly into the pump. This bogged down the pump. Now it’s time to remove the end plate from the pump and see what damage has been done.
Remember your vacuum system basics
QUESTION:
Maybe I’m not understanding vacuum truck basics, but why isn’t a bigger pump always better? Don’t you get more vacuum from a bigger vacuum pump?
ANSWER:
It’s amazing how many times we get this or similar questions. The assumption is that a vacuum pump is like a car engine: the bigger, the more powerful. And in some ways there are similarities, but vacuum pumps are different.
A vacuum pump has one primary purpose: to evacuate the air out of the vacuum tank. You can get a large vacuum pump and evacuate the air out of a tank faster, but is that an advantage? Pulling up to a jobsite, getting the vacuum pump running, and then getting your hoses ready for pumping take a little time. So wouldn’t the best of all possible worlds be to have your system ready to pump when you are in position and ready to work?
Remember, a small vacuum pump and a large vacuum pump will do the same thing: they evacuate the air from the tank to create vacuum. Once you have the vacuum you need to work, usually 18 inches to 20 inches of mercury, you’re all set. So this is where buying and using the right size pump comes into play. Why spend more money for a big pump when perhaps a medium-sized pump will be more efficient? A pump that is too small will require more time to evacuate the pump so there is the possibility of overheating the pump.
So, remember that tank size and pump size go hand-in-hand when trying to pump efficiently and profitably.
