Pumps . . . the Heart of the Pond
PUMPS COME IN AN ARRAY OF MODELS AND SIZES. Whether the water feature is a pond, waterfall, or pondless water feature, it will have a pump.
The pump is the heart of that water feature. It can also be one of the greatest sources of frustration contractors have when suppliers switch pump models at their whim. How many of you are still buying the same brand name pump from your supplier(s) that was offered 10 years ago, five years ago, or even two years ago?
We realize that the new models manufacturers come out with are just old models with minor improvements. Then you find that your supplier sent you a pump from a different manufacturer than the one you received with your last order.
You’re just beginning to gain confidence in a “new” series of pumps from the old manufacturer and all of a sudden, when you open the next order, you find there is still another “new” pump from yet another manufacturer. If you’ve been in this business for a while, you begin to realize how many different pump manufacturers you’ve gone through, and all those failures you’ve had in the field.
But let’s go on with pump installation. We know that pumps have a finite lifetime; hopefully, well beyond the warranty period. So we need to put much thought into the planning and plumbing layout before installing the pump.
Photo courtesy: Dave Jones
Knowing that sometime down the road the pump will cease to perform, we should utilize unions, cam locks or at the least Fernco type fittings, with the idea that at some point, this pump will have to be replaced. There aren’t very many things that are more frustrating than having to cut out and throw away $100 worth of fittings because the original installer glued his way out with no thought of tomorrow.
Yes, fittings cause friction and loss, too. Every glue joint causes turbulence to some degree. Even doing a splice with a double slip coupler will affect flow. Don’t overdo the glue (I’m guilty of this a lot).
I’ve cut out sections of piping that were clogged, only to find that an excess amount of glue squeezed up into the pipe during installation allowed debris to catch, build up and eventually clog the pipe. It most commonly happens in gravity flow drain lines. Pressurized lines usually blow out the obstruction, due to the increased pressure.
When in doubt, go up a size in pipe. Magnetic or Mag drive pumps are very sensitive to this issue. With Mags, I always go up one or two sizes of pipe, to reduce all the friction head I can. Mag drive pumps are some of the most efficient submersible pumps on the market. Their downside is they can’t handle head restriction much above 3 to 5 feet without their flow rate dropping off like a rock.
There’s another major mistake I see all the time in pump installation: the wrong size pipe. Not all pumps come from the factory with the discharge opening being the correct size to achieve optimum flow and performance from the pump. A pump rated at 4000 gph with a 1" discharge opening will not give you 4000 gph with 1" plumbing. It will give you just over 2000. Give the same pump an upgrade to 2" pipe and you get the flow you expect.
You have to get your hands on a flow and friction loss chart. Then use it when designing a system. At least familiarize yourself with the approximate flows with different diameter pipes and their fittings. That 3600 gph submersible with the garden hose adapter is only going to move 10% of the water that it is capable of moving through 2" pipe if you stick a garden hose on it.
If you have 3' of elevation head but use undersized piping, giving you another 7' of friction head, you’re going to be very disappointed in the pump’s performance. It won’t be the pump’s fault; however, it will be designer and installer error. The same goes for high efficiency, low rpm external pumps.
They are, hands down, the best choices to move a lot of water with low electrical consumption, if the plumbing and design are correct.
Over the years, I’ve experienced pumps that have malfunctioned. My greatest concern is how much of a hassle it will be to get a warranty swap. One of the most common practices is for the supplier to have you ship the failed pump back to them, usually on your dime. Then they have to get around to doing their own testing to determine if the pump really has failed, and whether or not they’ll cover it under warranty. Then they might ship you a new pump.
Now, while these two, three or four weeks have passed, your customer is sitting there screaming about a pond without a pump, possibly with fish stressing or even dying from lack of oxygen and proper circulation through the filtration system. The customer becomes rather impatient, and rightfully so.
As this is going on, my customer is annoyed with me and thinks I’m giving him lousy customer service. I, on the other hand, am spending hours going back to this customer to pick up the pump, call the manufacturer, ship back the bad pump, etc. All this is costing me time and money. I sometimes wonder, are we just un-compensated patsies of manufacturers?
Working with pumps all these years, I know what to check for to see why the pump has malfunctioned. We check the impeller for blockages, check the line voltage to the pump, check for locked up or wobbly impellers—you know the drill.
It should be as simple as a phone call to the supplier, to get a replacement on the way with a return authorization and a shipping label. I put the old pump in the new box, slap on the new label and ship it back. End of story. Simple, right?
Not quite. Although there are some suppliers that do respect you as a professional and do business that way, many don’t. Those suppliers that don’t accept your word and have such a high hassle factor, it makes you want to take your business elsewhere.
I do very little or no business with companies that follow the aforementioned policy due to the simple fact of the multiple frustration factors introduced in this scenario.
You begin to wonder where the field testing was done; better still, was any field testing ever done? You ask yourself, “How long has this pump been out on the market? Why did my supplier change brands?
What about warranty service?” I don’t know how many times I’ve gone through the same old Q&As with my supplier when failures happen.
Why should we take the heat for a high percentage of failures just because a supplier got a killer price break from some obscure new pump source in Pongo Pongo? It boils down to how much you trust your supplier to take care of you. Some suppliers do well; others, not so well in how they handle warranty issues. What’s your supplier’s track record? This has been and will, more than likely, continue to be the downfall of more than one supplier in the history of our industry.
There isn’t much we can do with pump manufacturers, other than to buy the best. Then, if we can cut down on designer error and serve the customer and industry with professionalism second to none, we can eliminate a lot of backtracking and re-visits to clients that we don’t get paid for in the first place. I hope you got something useful out of this article.
EDITOR’S NOTE: Dave Jones is the owner of The Pond Professional, Woodstock, Georgia.