The water pump is now an essential component of a rainwater harvesting system. This is because there now are components that can help make rainwater (and water from other sources, for that matter) cleaner, and these are meshes, filters, and filtration systems.
But in order to get the most out of a water pump installed in your home, it’s important that the pump purchased is one of the correct size in the first place. Read on to know why.
Why Get a Pump of the Right Size in the First Place
Although gravity can make some rainwater collection systems work, many systems need a pump, which can be quite expensive. So imagine how the rainwater harvesting system would work if an installer will just recommend or setup a standard 3/4 HP or even a 1 HP pump just because they believe it’s able to do the job right. While in some cases it can do the job right, in most other cases it’s undersized or oversized. To best describe the drawback of having a “standard-sized” pump is to imagine a high-powered engine set up on a go-kart; although said engine can make the vehicle run, it consumes more fuel than an engine of the correct size. Worse, it won’t last long because it is hindered from functioning at peak efficiency.
Therefore, a pump of the wrong size can waste so much energy, won’t last long in your home, and costs much on maintenance.
A pump with the wrong size will drain a homeowner of several hundred to thousands of dollars in just a short time. What is designed to be able to last ten to fifteen years will need to be replaced by the third or fourth year, and the homeowner will be forced to shell out another several hundred or thousands of dollars on another pump. The homeowner will also need to pay more in electrical power, not to mention the labor costs that are involved in pump replacement.
Other Things to Know About Pump Purchase
It’s also worth mentioning that a wrong-sized pump is not the only problem that’s costly to a homeowner—so is getting the wrong type of pump. A pump that’s used in a rainwater harvesting system is quite different from a pump that’s used for irrigation systems and wells. A pump for an irrigation system is designed to push water to drip heads or sprinklers and usually require fewer gallons a minute and pressure for every square inch than many rainwater systems. As for well pumps, these are designed to be capable of pulling water from depths greater than the total distance of all pipes in a rainwater harvesting system.
Depending on how the rainwater harvesting system is designed, its pump might have to pull water from a cistern and make he pressure that’s essential for its intended use. Hence, in many cases, a pump to go with your above ground water storage tank should be sized to pull AND push water.
Proper rainwater pump sizing requires that you have sufficient knowledge of the locations of both water storage and pump, plus the way collected water will be used. Remember that every system is a little different. From there, it follows that there is no single design for a harvesting system.
Complicating matters even more is the fact that neither industry nor government has mandated one way of depicting the performance of a pump. A number of manufacturers include a number of details pertaining to performance, while others provide insufficient data to determine if a certain pump indeed is a good pump.
In addition, performance information sometimes is published on the external part of the box, whereas other manufacturers publish such information in a manual.