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Freezing temperatures in the winter months pose a considerable but entirely avoidable hazard to your water pump. Before the weather gets too cold and water begins to freeze, it's important for water pump owners to take precautions that ensure the proper operation of irrigation pumps, fountain and pond pumps, well pumps, and centrifugal pumps come warmer seasons. During the winter months, temperatures often drop below freezing, and despite the strength and power of your water pump, the frozen water will be quick to crack the casing on your equipment. Rather than leaving your water pumps to brave the winter weather on their own, winterizing your water pump is a surefire way to protect your equipment all season long. 

Winterize Your Water Pump

Winterizing your water pump is surprisingly simple, and only takes a few minutes to complete. A few minutes of work now is better than discovering costly maintenance issues, or worse, the need for a brand new water pump come spring, right? 

Drain and Store

Water pumps in shallow or surface level areas must be winterized for cold weather. Pond and foundation pumps, pool pumps, and irrigation systems must all be drained, and should never be allowed to freeze. In cold weather areas, draining and winterizing an above-ground water system is common sense, but in normally warmer southern states, water pump operators might be more easily caught off guard with a surprise overnight freeze. 

When you're dealing with a jet or centrifugal pump that you're not going to use for a few months, draining the system and moving the pump to a warmer location is the best solution. 

How to Drain the Pump's System 

To drain the pump, remove the drain plug on top of the pump case, or open a faucet. This allows air into the pump body. Then, remove the drain plug on the bottom of the pump case. This allows the water to flow through and out of the pump body. After you've drained the pump, there will still be a bit of remaining water that's stuck in the suction and discharge pipes. Use an air compressor to blow out the excess water.

Running Water

Water will expand as it freezes, and without the space to handle extra volume, the ice will eventually break inside the pump or its piping. In year-round homes, well pumps can often sit idle for long enough that water may freeze solid. If temperatures drop and remain very cold for an extended period of time, allowing a small amount of water to run continuously through above-ground water systems, plumbing, or pump equipment until temperatures rise again can prevent freezing while potentially saving you thousands of dollars in future maintenance or repairs.

Final Steps

To completely protect your water pump against any water that might remain inside the casing even after draining, you'll want to fill the pump body with food-grade polypropylene glycol. Make sure to never use ethylene glycol (or RV anti-freeze) in your water pump as it is extremely dangerous. Insert the bottom drain plug, pour in the propylene glycol through the top port, and reinsert the top drain plug. 

Do All Water Pumps Need to be Winterized?

Water system motors that are used in wells, fountains, and aerators are typically filled with a water based solution. In a deep well, you generally won't need to worry about the motor freezing; however, in fountains or ponds, you'll still need to protect your water pump. If you do choose to remove the pump, store the motor somewhere that it will be completely protected from freezing. Another winter storage option for pond, fountain, and aerator pumps is to sink or weigh the motor to the deepest possible level, ensuring that the motor is placed well below the lowest freeze level.

In the spring, simply complete these steps in reverse order to get your water pump up and running. If required, don't forget to re-prime your water pump. Still have questions about water pump maintenance, or what the best water pump is for your operation? Contact an Absolute Water Pumps specialist today. 

As we work with water pumps, we find that pressure is presented to us in two common units: PSI (pounds per square inch) or feet of head. As we size a pumping system, we'll want to accomplish building pressure (PSI). The relationship between PSI and feet of head is that 2.31 feet of head = 1 PSI. 

Translated, that means that a column of water that's 1-inch square and 2.31 feet tall will weigh 1 pound. 

Or, one-foot column of water that's 1-inch square weighs .433 pounds. 

These two numbers, .433 and 2.31, are the conversion numbers used to convert from one unit to the other. 

How to convert dynamic head to PSI:

As we learned in school, to solve a problem we need to be in common units. As we work through a problem, we need to convert to the unit that is most common – feet of head. 

When working with pumps and plumbing, you'll work between feet of head and PSI routinely. Becoming familiar with the units and where they come from will make your work easier and faster. 

So, let's do a short conversion exercise: 

We are looking to purchase a pump, that we will call Model number: XYZ123.  XYZ123 pump is capable of pumping a maximum of 100 feet of total dynamic head. So what is the maximum pounds per square inch?

100 feet of head ÷ 2.31 = 43.29 PSI

However, this would be at what is called “dead head”.  The dead head of a water pump simply means that there is zero (0) flow of water at the maximum total distance of head.  

In the example above, we could say that XZY123 pump is capable of a maximum of 100 feet of total dynamic head (total head feet) and a maximum pounds per square inch of 43.29 PSI.

Now, let’s say that we only need to pump water a total of 40’ high. Using XYZ123 pump, how much pressure will we have at 40’?

40 feet of head ÷ 2.31 = 17.32 PSI

Still not sure what is happening? Picture for a moment a water hose that you hold in your hands. You are watering your garden, but you can’t quite reach the tomatoes that are at the back of the garden. It’s been a long week and you are tired and don’t want to walk all the way across the garden.  You decide the simplest solution is to place your thumb over the end of the hose as opposed to walking the distance to the tomatoes. What happens?

The water goes farther but not as much water comes out of the hose and it takes a bit longer to give the tomatoes the amount of water that they need. While you are able to reach the tomatoes with the water, because the flow has been decreased it takes you a bit longer.

What you have done, even though we don’t tend to think of it this way, is that you have increased the pressure (back pressure) because you have actually made the outlet a smaller diameter by placing your thumb over the end of the hose.

So, while less water is now flowing out of the end of the hose (discharge), you have increased the pressure and now you are able to spray water a further distance (total head).

An easy rule of thumb (pun intended) is to remember:

• Higher head = Higher pressure (PSI) but lower flow (GPM)
• Lower head = Lower pressure (PSI) but higher flow (GPM)

How to covert weight of a cubic foot of water:

If you have 1 cubic foot of water holding 7.48 gallons, and the weight of one gallon of water being 8.33 pounds, you'll get 62.37 pounds per cubic foot of water. 

But don't become confused with mass and pressure. 

If you lift our 1 cubic foot of water to 23.1 feet of elevation, we will only generate 10 PSI of pressure at the bottom where we started, as opposed to the 62.37 pounds mass we lifted up in the air. 

So, let's apply this knowledge to practical use: 

Let's say we have a lake cottage on the top of the bank, and we want to know how much pressure our pump needs to push the water to the top of the hill. We don't have time for a surveyor, or the money, but we still need to know the elevation change from lake level to cottage. 

If we take a garden hose or tub and run it up the hill, put a pressure gauge at the bottom, then fill the hose or tube with water, we can tell what the elevation is on the hill. If the gauge reads 40 PSI when the hose is filled with water, we know that the elevation is 92.4 feet. We simply take 40 PSI x 2.31 which equals 92.4. This is not distance, but feet of head. We may have run 1000 feet to rise 92.4 feet, but either way, we will have 40 PSI to overcome to pump water to the top of the hill. 

To illustrate the effects in relationship of head vs. PSI under static conditions, we must note several items. 

The amount of water with the same height will give the same pressure at the bottom no matter how many gallons are in the tank or the size of the pipe. Remember we said not to confuse mass with pressure. The common element is the head which is 115.5 feet, and if we divide that by 2.31, we will come up with 50 PSI. These conditions are true for static conditions. If the water starts to flow, we'll incur friction loss, and for the same height of water, we will have less pressure at the bottom. 

We'll discuss friction loss in our next blog. 

Have you ever thought about how altitude might affect a water pump? A lot of people don’t, but it is a very important thing to be aware of, as it can positively or negatively impact the performance of your water pump. Altitude can affect the performance of a water pump much more than you may realize. Whether it is increasing the fuel needed to operate a pump at an increased altitude, decreasing or even increasing the pump's efficiency, or causing other problems in the water pump, there is much more to operating a pump at a higher or lower altitude than you may have initially thought.

Let’s talk about how a higher altitude affects a pump. The higher the altitude is in a given location, the lower the pressure will be. This happens because as you go higher, the oxygen thins out and becomes less dense. Oxygen is a gas, meaning that as the altitude increases, the oxygen decreases in density. Essentially, this means that there is less air the higher you go. The opposite is true if you decrease in altitude. The farther down you go, the denser oxygen becomes, and the more air there is. As this pertains to pumping water, this thinning or increasing of the density of air affects the pressure of the pump. The higher the altitude, the thinner the air as you already know. But the air getting thinner also means that there is less pressure the higher you go, and the lower you go, the more the pressure increases. The pressure loss is the biggest part that affects a water pump, and it is called atmospheric pressure.

The lower the atmospheric pressure, the harder it will be for the pump to do its job, which is to pump water or other liquids from one location to another. The decrease in pressure, due to higher altitude, means that the pump will have to work much harder. This also means that the water pump will lose how far it can pump the water or other liquid (total dynamic head loss). Furthermore, the lack of pressure means less suction power (suction lift) and pumping power the higher you go. This is obviously not a good thing, as a pump's purpose is to move liquid, and if it can’t do that as well as it is supposed to, significant losses will be experienced, and the manufacturer's attainable specifications and attainability will not be able to be met. Simply put, if the pump manufacturer states that there is maximum total dynamic head of 200’ and maximum of 500 GPM (gallons per minute) at 4,000 feet above sea level, you can expect that those numbers will be significantly lower (see chart below).

Specific gravity suggests that water can be pumped from less than or equal to 26 feet down when operating at sea level, which is to say that when you’re at sea level with a water pump, you can only expect your pump to have a maximum suction lift of 26 feet or less. This number increases as you go lower than sea level, because there is more atmospheric pressure. The higher you go, however, the less suction lift you can expect from the pump. The general rule of thumb is that for every 1,000 feet above sea level, subtract 2 feet from the 26-foot number of suction lift. One way to improve this issue is to place the water pump as close to the liquid source as possible, so it has less distance to travel when trying to draw water from the source to the pump.

The suction lift in a pump is the pressure on the suction side of the pump, meaning the part of the pump that sucks up water and other liquids using pressure. The higher you go, the less effective it is. Here is a chart showing the effects of increased elevation on suction lift.

Another important part of a higher altitude and its effects on a water pump is the engine fuel. A gas or diesel engine will burn more fuel at a higher elevation because the oxygen is thinning/decreasing in density. Gas and diesel engines rely on certain specific oxygen contents, and the higher you go, the less there are of these oxygen contents, essentially meaning that the engine must work harder to function, thereby burning more fuel. It also means that the engine's rpm (revolutions per minute) slow down, which also decreases the GPM (gallons per minute) and total head the higher you go. This can be a major problem, as many people may not account for the extra money of more fuel because of the higher altitude nor consider the combined effects of pump capability loss due to altitude, in addition to losses from the gas or diesel engine. Gasoline and diesel engines lose approximately 3-3.5% of their power for every 1,000 feet of elevation above sea level. The following is a chart showing how the increase in elevation affects the engine, which in turn affects the GPM and head of the pump.

There is no solution that involves fixing or upgrading your gas or diesel engine to prevent or improve this. However, one very easy solution to this problem would be to buy an electric engine. This would help improve two things immediately: one would be the elimination of extra fuel you would burn in a gas or diesel engine at a higher altitude. An electric engine would mean no fuel cost, and would cost much less to run, depending on the size. The second thing an electric engine would improve would be the GPM and head of the water pump when compared to a pump with an engine. Because an electric motor is not affected by altitude or atmospheric pressure (though the pump head is), it could operate at full capacity, and keep the GPM and head at 100%, which is what any pump owner wants. Another thing to bear in mind is the size and power of the water pump itself. A pump that might do well at, or a little above sea level might not be strong enough to meet your pumping needs at a higher elevation of say 6,000 feet. Always be aware of how high the altitude is going to be where you are using the water pump before buying it, as your specific elevation may require a stronger pump.

Overall, using a water pump at a higher altitude can lead to complications and a decrease in efficiency, especially with pumps that use a gas or diesel engine. There are, however, some solutions to this problem: buying an electric engine, placing the pump close to the water/liquid source, and investing in a more powerful pump. Despite this, there is no sure-fire way of beating any sort of deficiency with a water pump at a higher elevation, because there is nothing that can be done about the higher elevation/altitude. It’s good to always be aware that your water pump may not be performing as well as it could because of a lack of oxygen or low atmospheric pressure. Being ready for a possible decrease in your pump’s power is always a good idea and knowing what the problem might be could help you save money and time, both of which are extremely important to everyone.

If you will be pumping at higher elevations, we would encourage you to speak to one of our Applications Specialists. They would be more than happy to help you find the correct water pump for pumping water at higher elevations.