How To Buy A Sump Pump

Buying a sump pump can be a daunting task because there are so many brands, models, types and features. Rather than buy what your neighbor likes or go to your local Big Box store and conclude the best selection is based on which pumps are on the store shelves, use the following guide and its tree steps to understand the factors affecting your selection.

Sooner or later your existing sump pump will fail and you will wish you had taken more time before an emergency situation occurs to know how to buy a new sump pump.

Buying a sump pump becomes easier if done in a methodical way. Here are three major steps to consider.

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Three sump pump parts: the switch, pump and motor housing, and impeller, make it possible for a sump pump to perform its function properly. Without these parts a sump pump would not operate effectively.

The switch activates the pump motor to start automatically when the water levels in the sump pit reach a certain height. This eliminates the need to manually plug the pump into the electrical outlet to run it and pull the plug when the pump should stop running.

As the water level monitoring mechanism senses a change in pit water height, a change in pit water pressure or a change in pit water electrical current grounding, the switch closes the electrical circuit which sends electricity to the pump motor to run it. Once the water level drops, the switch electrical circuit opens which stops the pump.

The three common switch types include: 1) The Float Switch 2) The Diaphragm Switch 3) The Electronic Switch .

Float Switch

The Float Switch relies on a float that rises and lowers based on the basin water height. As the float rises to a preset height it activates the switch (completes the circuit) which turns the motor on. When the water lowers causing the float to lower, the switch turns off (the circuit is incomplete) and the motor turns off.

The float switch requires replacement every three to five years depending upon frequency of use. Rather than discard a cast iron pump every three years, replacing a failed switch is environmentally smart. Many brands like Zoeller and Wayne make replacement float switches and other parts easy to buy online and install.

Two Float Switch Types: The Tether And The Vertical

Tether Float Switch

The tether float switch is preferred by those who have a wide pit, 18 inches, and wish to customize the switch ON height. The tether switch disadvantage is that it easily gets hung up on the basin wall or caught on something in the pit.

Vertical Float Switch

The vertical float switch is preferred by those who wish to install a primary and battery backup pump in the same pit. Vertical float switches take less pit space.

- Vertical float switches come in two styles: the magnetic vertical and the snap action vertical.

- We prefer the snap action vertical because its float guard is more protective against pit wall hangup and the float switch is not affected by water contaminates such as calcium carbonate.

- Wayne and Zoeller are known for using the vertical snap-action float switch. Both brands claim testing these float switches to one million pump cycles. Some Everbilt, Little Giant and Red Lion use the snap action float switch as well though do not publish testing results.

- Brands such as Liberty Pumps, Flotec, Superior and some Basement Watchdog and Red Lion models use the magnetic float switch.

- Brands such as Zoeller, Wayne, Everbilt and some Little Giant and Red Lion use the snap action float switch.

Diaphragm Switch

The Diaphragm Switch uses a membrane found on the side of the pump. The membrane convexes and concaves as the water rises and lowers. It is the water pressures effect on the diaphragm that causes the switch to activate and cause the motor to turn on.

Electronic Switch

The Electronic Switch consists of a sensor in the water which is affected by water pressure or presence.

This switch type is great because it has no moving parts, does not get hung up and does not require extra basin space because it is attached to the PVC discharge pipe.

Installation of an electronic switch requires bypassing the traditional switch which is part of the pump or to install a manual pump and use the electronic switch to automate it.

Several styles of electronic switches exist. Not all of them are reliable. Our favorite is the electronic switch, HC6000 by Hydrocheck.

Initially the Hydrocheck engineer gave us some tips for a successful installation. There is a very small current, not enough to cause electrocution, sent through the pit water and it must be grounded. To do this we attached the HC6000 to a one-half inch diameter PVC pipe 18 inches in length. This configuration was zip tied to our existing PVC 1-1/2 inch discharge pipe at a custom height for our sump pump set up. This configuration makes the HC6000 very reliable. We bypassed our existing pump switch. So our pump uses its motor but the NC6000 as its switch. Our HC6000 is still working perfectly after 13 years. It was installed in 2011. It is so wonderful to own such a dependable switch.

Motor Housing

Most pump brands use third party motors made with stainless steel housing. Zoeller Pump Company still builds their own motors using cast iron housing. This ensures better heat dissipation and a tighter fit thus eliminating air pockets which contribute to additional motor heat during heavy continuous pumping.

Pump Housing

The material used for pump housing affects the motors longevity. The best pump housing is that which will dissipate heat, not crack under heavy usage or warp because of increased heat during long periods of continuous pumping, and will not corrode from sump pit water and its chemicals.

Cast-iron is powder-coated with an epoxy finish to resist corrosion. cast iron dissipates heat well; stainless steel is next best. Zinc alloy and aluminum are also better than thermoplastic which rates as the poorest material to use. Thermoplastic traps heat.

The Motor

The motor is the heart of the sump pump. It powers the pump to move water from the sump basin out of the home. Without a functioning motor, the pump cannot operate.

A sump pump relies on the motor to drive the impeller which causes a swirling motion that forces water out of the sump pit and through the discharge pipe or hose.

Motor Horse Power

The power of the motor, defined by its horse power, impacts how much water can be pumped at a specific height during a measured time period. Thus choosing the right size of pump motor is very important. Too much power causes motor short cycling and premature wear, but too little results in a sump pit overflow.

The GPH range for 1/3 HP sump pumps is 1,740 to 2,040 GPH at a 10 foot vertical height for 1/3 HP. Superior and Little Giant 1/3 HP pumps are at the lower end of the GPH range.

For 1/2 HP sump pumps the GPH range is 3300 GPH to 4,200 GPH. Zoeller, Wayne and Liberty Pumps 1/2 HP pumps are at the higher end of the GPH range.

The most common mechanisms used are the screen or vortex impeller. Screens require maintenance because they get clogged easily if debris or small pebbles are present in the basin.

Top suction used by Wayne pump models have no screen and no vortex impeller. They do not handle solids. They remain in the basin.

Impeller Role And Style

The impeller actually causes movement of water from the pit with its swirling centrifugal force. It begins spinning around the motor shaft as the motor's energy converts into mechanical energy when the pump turns on.

As the impeller pushes the water out of the pit, more water flows in to fill the void, forcing water out through the pipe in the sump pit.

Impellers come in two styles: vortex and non-vortex.

- A vortex impeller means the impeller handles small solids, doesn't clog as easily, creates suction on the bottom side and needs an air-lock hole.

- A non-vortex impeller does not handle small solids, creates top suction if the volute is below the impeller, does not need an airlock hole and is more efficient.

- By industry definition a pump with a non-vortex impeller is a sump pump; while a pump with a vortex impeller is known as an effluent sump pump.

The best style is the vortex impeller because it does not get clogged by small pebbles or debris in the pit. Solids handling size varies from one-half inch to three-quarters inch solids.

Understanding your needs and existing sump pump system prevents the mistake of buying a sump pump that sounds good on paper but does not meet your intended use or need.

In our earlier years we shopped Big Box stores and relied on the saleman to help us choose our sump pumps. We really didn't know anything about our system and didn't realize that by knowing our system better we could have made better decisions. But know we know so we want to help others by sharing our knowledge and experience.

Ask these questions about your existing system to help you understand your sump pump system better so you can make a better sump pump choice.

Select a question to find responses in the section below; otherwise scroll down to read them all.

Does a heavy rainstorm cause concern? Does your pump barely keep us with the ground water entering the Pit? Is your current system meeting your needs?

If your current sump pump keeps up, great. Installing the same model and brand is a great solution. If not keep reading to discover factors that can improve your current situation.

Several years ago we asked ourselves about our existing sump pump system. That's when we made a change. Our old sump pumps were failing every two years or so and we didn't know why. Finally we learned that our ground water contained an above average amount of calcium carbonate. The calcium carbonate was clinging to the vertical magnetic float rod and float top. This caused the float to stick. We learned that we could clean the rod and float with a vinegar solution every year, but our lifestyle is too busy for that kind of maintenance.

So we did our research and found better options. We installed a Zoeller M53 which uses a vertical snap action float switch. For one of our other main pumps, we bypassed the vertical magnetic float switch and use the electronic switch HC6000 made by Hydrocheck.

Our old sump pumps could not handle the volume of ground water entering the pit during heavy rainstorms. Every heavy rainstorm the pumps would run continuously and the water would reach the rim of the basin. We had no peace of mind.

We didn't want a flood in our finished basement so we stayed at the basin ready to bail out water with buckets when those heavy rains came. Peace of mind returned when we found a solution. We added an adjacent pit capable of housing two sump pumps, a main pump and a battery backup pump.

Is your sump pump too powerful? Installing too large of a pump for the small volume of water in your basin during heavy rain storms is just as bad as having too small of a pump installed to handle large volumes of water during heavy downpours. Too large of a motor causes motor short cycling and early motor burn out.

Knowing how much water pumps from the sump pit during heavy rainstorms aids in determining the horse power needed. It is easy to measure the size sump pump needed.

If you are looking for a new pump, look for sump pumps that can handle the amount of flow per minute. To be prepared for extra heavy rainstorms, add 10% more GPM.

Sump Pumps By Horse Power And GPH At 10 Feet

- One-fourth horse power sump pump models vary in GPH at a 10 foot vertical height. Liberty Pumps 240 Series pumps 1,380 GPH. Zoeller M49 pumps 1,500 GPH.

- One-third horse power sump pump models offer following GPH at a 10 foot vertical height. Zoeller Mighty Mate Series (M53, M57) and Premium Series M63 pump 2,040 GPH. Wayne Model CDU790 pumps 2,700 GPH. Liberty Pumps 250 Series pumps 2,160 GPH. Superior Pump Models 92331 92341 pumps 1,800 GPH Glentronics (Basement Watchdog) Model SI33V pumps 3,200 GPH. Little Giant Models 506125, 506158, 506162 pumps 1,740 GPH. Red Lion Model RL-SC33V pumps 2,460 GPH. Star Water Systems Models 3SVS and 3SDHL pump 2,520 GPH.

- One-half horse power sump pump models offer following GPH at a 10 foot vertical height. Zoeller Premium Series M95 and Flow Mate M98 pumps 3,660 GPH, Wayne CDT50 pumps 3,150 GPH; SPF50 pumps 2,900 GPH and CDU800 pumps 3,840 GPH. Glentronics Basement Watchdog SI50V pumps 3,800 GPH and Model SIT50D pumps 3,540 GPH. Red Lion RL-50C pumps 3,420 GPH and RL-SC50T pump 3,000 GPH. Liberty Pumps 280, 281 and 293 Series pump 4,260 GPH. Superior Pump 92501, 92507 and 924511 pump 3,480 GPH; Model 92511 pumps 3,400. Star Water Systems Models 5SEH and 5STS pump 2,880 GPH. Little Giant 510803 pumps 3,300 GPH; 509801 pumps 3,780 and 5080458 pumps 3,240 GPH. Flotec Models E50VLT and E50TLT pump 3,680 GPH,

- Three-fourth horse power sump pump models offer following GPH at a 10 foot vertical height. Wayne Pumps CDU980E pumps 3,500 GPH. Flotec E75VLT pumps 4,020 GPH. Superior Pumps 92751 pumps 92751 pumps 4140 GPH. Liberty Pumps 290, 293 and 297 Series pump 4,260 GPH.

- One horse power models offer following GPH at a 10 foot vertical height. Wayne Model CDU1000 pumps 3,840 GPH. Superior Pump 92151 pumps 4,500 GPH; 92181 pumps 4,520 GPH.

A sump pit that is at least eighteen inches in diameter and 24 inches deep is ideal. A twenty-four inch diameter pit is even better.

A large pit gives enough room to install any brand of sump pump. A small pit limits the pump selection options available.

Manufacturers are making good narrow sump pumps today. A narrow primary pump means there is also room for a backup pump to sit on the pit floor next to the main pump.

- The Basement Watchdog Model BW1050 and Little Giant Model Series 5 and 6 are a little over 6 inches in width.

Most pits have small pebbles and debris and if not now they probably will have such in the future; therefore to play it safe it is best to install a pump with a vortex impeller. These pumps are usually called effluent sump pumps.

- Liberty Pumps, Zoeller, Pentair Myers, Pentair Hydromatic, Red Lion, Everbilt and some Little Giant, Flotec and Basement Watchdog models use a vortex impeller. Wayne pumps use top suction so there is no vortex impeller.

The vertical height, also known as head height, impacts the performance of your sump pump. The greater the vertical height water must be pumped, the lower the gallons pumped per minute. The greater the pumps horse power, the greater its pumping capability. Maximum head height or shut off height defines the vertical height at which the pump can no longer pump.

Manufacturers document the pumping capability per minute or per hour at different vertical heights for each model. Knowing the maximum vertical height the water must be pumped aids in determining which sump pumps are built to handle the water flowing in and out of your pit during heavy rainstorms.

- Superior Pump Sump Pump models feature the greatest maximum vertical head lift at an average of 25 feet. Other brands fall within the range of 19 - 22 feet.

The existence of calcium carbonate in ground water is not visible; however certain areas of the county do naturally contain more calcium carbonate than others. Calcium carbonate concentration is higher in southwest United States and states such as Dakotas, Illinois and Ohio.

The degree of calcium carbonate becomes important because it clings to certain types of pump float switches. Vertical magnetic reed float switches show the most negative impact.

The vertical magnetic float switch is most impacted by calcium carbonate. Cleaning the float rod and the top of the float periodically limits its impact.

A vertical snap action float switch and some electronic switches are not impacted by calcium carbonate.

Many home owners choose to service their own sump pumps and replace float switches when they fail rather than discard the pump.

Replacement float switches are easy to purchase online and install. It doesn't matter the float switch type, replacement switches are available. In fact Zoeller gives homeowners two options for snap action switch replacement: 1) The budget friendly way: Buying just the switch and replacing it by unhooking some switch wires and loosening more screws or 2) The easier way: Buying a new switch case with a new switch already installed. Option two is recommended if you are trying this for the first time.

Do-it-yourself homeowners have several options for easy to install sump pumps. To make installation easier there are many pump manufacturers who pre-assemble the discharge pipe to the main pump. Other manufacturers assemble a main pump and battery backup pump as one unit calling it a combination sump/battery pump. Most of these pre-assembled packages also include the discharge pipe so the home owner only needs to connect the discharge pipe to the homes existing discharge pipe. Before buying always check the dimensions of a preassembled sump-pump to make sure it will fit in your basin.

Installing or replacing a sump pump is not as hard as one would think. Basically all sump pumps are installed the same way even though they have different dimensions. We provide the steps for installing a Zoeller sump-pump. Check out the steps.

Many sump pump options exist; however your preferences and your water pumping needs need to take precedence.

The best sump pump for your water pumping needs is the one that fits into the basin, can pump enough gallons per minute (GPM), has replacement parts if you intend to keep the pump longer than its first switch failure, is made of cast iron, has a vertical snap action float switch not affected by calcium carbonate, and has at least a three year warranty.

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