Motor Housing - Do Water Chemicals Affect Any Motor Housing Materials?
Sump pump motor housing made of thermoplastic and bronze are exremely resistant rust. Stainless steel is not easily affected either. However, materials such as cast iron, aluminum, and zinc alloy can be affected by the chemicals found in water and corrode or rust Pump manufacturers use an oxide resistant epoxy coating to protect the motor housing. Therefore, submersible pump housing made of any of these materials will be durable enough to last the life of the pump motor itself.
Heavy Duty Pumping - Does Continuous Pumping Affect The Housing?
Heavy duty pumping causes the housing material to strain and can cause cracking or breaking; therefore the type of housing material used for submersible sump pumps that will undergo heavy pumping does mater. Cast iron is strongest and most unlikely to crack. Carbon steel is second strongest highly unlikely to crack. Bronze and stainless steel are third strongest and unlikely to crack. Aluminum is fourth stongest and unlikely to crack. Thermoplastic is weakest and most likely to crack.
Heavy continuous pumping also causes the pump housing material and parts to get hot and potentially warp. Bronze is least likely to warp. Cast iron second least likely to warp. Carbon steel, stainless steel and aluminum are third least likely to warp. Thermoplastic is most likely to warp.
In conclusion, classifying material corrosion, cracking and wraping as sump pump durability, pump materials made of bronze are most durable. Cast iron materials are second in durability. Carbon steel and stainless steel are third in durability. Aluminum is fourth in durability. Thermoplastic is least durable. Therefore installing a thermopliastic sump pump for heavy continuous pumping for long periods of time is not recommended.
Switch - Does Number Of Pumping Cycles Affect The Switch?
The number of pumping cycles does affect the submersible pump switch. Each manufacturer tests their switch and knows approximately how many pumping cycles it can perform before failture. This is why pump manufacturers recommend the switch be replaced every two or three years.
As a homeowner you know how often your sump pump runs and therefore you can estimate if your switch will last longer than two or three years.
Submersible pump switches are generally mechanical. Those include the tether float switch, the vertical float switch and the diaphragm. Electronic switches are not mechanical and in general last longer. Those electronic switches that are not affected by water chemicals or circuit failures are very durable.
Impeller Design - Does Design Affect Pump Failure?
Unless your sump pit is completely free of sludge, small pebbles and debris or you clean your pit regularly so sludge and debri do not build up, your sump pump impeller will fail to rotate and push the water from the sump pit.
The two most common ways manufacturers design their pumps to handle such things is by using a screen to cover the area where the water from the pit enters the pump or to install a vortex impeller which is capable of handling debris.
Some manufacturers place the screen at the top of the pump rather than the bottom which does lessen the problem of debris getting caught in the impeller and causing a pump failure. Rather than having to clean a screen it is recommended a homeowner install a submersible pump that has a vortex impeller.
Preset ON-OFF Height - Does ON & OFF Switch Setting Affect Pump Motor?
Most submersible sump pumps have a solid state switch which means the switch comes attached to the pump. A solid state switch does not allow a homeowner to change the ON and OFF height at which the pump is activated and shuts off.
There are a few manufacturers who have an external float switch which allows the homeowner to attached the float switch to the discharge at the desirable ON height; however the OFF height cannot be changed.
If the sump pump only runs during heavy rains, the inability to change the height of the switch has little effect; however, if the pump runs even when there is no rain because of a high water table, the pump will turn ON and OFF frequently running only for a few seconds. This causes pump short cycling and does cause wear of the motor.
There are two options for the homeowner with a pump that runs frequently for very short periods of time. First, the homeowner can install a non automatic sump pump and an external dual switch which allows setting of the ON and OFF height. Second the homeowner can install an automatic sump pump that has a piggyback switch, tie up the flost switch to the discharge pipe and add an external switch with dual switches so both the ON and OFF height can be determined by the homeowner.
Sump pit size definately affects pump selections available to the homeowner, especially when both a primary submersible sump pump amd a backup pump should both be installed on the floor of the pit. Fortunately, advances in technology have helped manufacturers to make narrower sump pumps and still maintain the pumps efficiency, stability and pumping capability.
Sump pit size definately affects pump selections available to the homeowner, especially when both a primary submersible sump pump amd a backup pump should both be installed on the floor of the pit. Fortunately, advances in technology have helped manufacturers make narrower sump pumps and still maintain the pumps efficiency, stability and pumping capability.
PiggyBack Switch - Is Piggyback Switch Useful When Pump Switch Fails?
A submersible sump pump with a piggyback switch gives the homeowner an option to run the pump manually if the switch should fail.
A piggyback switch for the float has a three pronged plug which is for plugging into a wall socket. On the backside of the plug is a plugin socket for plugging in the sump pump motor cord. If the float switch fails, the pump cord can be removed from the piggyback switch and plugged in directly to a wall socket. This works great in an emergency if the homeowner is home and can manually plug in and pull out as necessary to remove the water from the pit. Many external sump pump switches use the piggyback design.
Manufacturers GPM (Gallons Pumped Per Minute) charts - Are They Calculated The Same Way?
Not all manufactures GPM charts are calcuated the same way. You may have wondered why a highly recommended sump pump manufacturer like Zoeller does not make 3/4 HP sump pumps. The reason is because their 1/2 HP sump pump can pump as much water as a 1/2 HP pump.
Most manufacturers determine gpm (gallons pumped per minute) at a specific vertical height by only including the friction caused by the vertical lift. Zoeller includes friction caused by vertical height of discharge pipe, horizontal length and friction cause by each elbow in the discharge piping. Including all of these friction items could add a minumum of 3 to 5 gallons a minute.
How Does The Submersible Sump Pump Compare To Other Sump Pump Types?
Submersible sump pumps are used by home owners more than any other sump pump type. They are most suited for pumping water from a sump pit because they are meant to be submersed in water and are built for continuous operation.
Compared to the battery backup sump pump and water powered sump pump, they offer
Most replacement parts including float-switches. Thermoplastic housed pumps do not have replacement parts. They are meant to be thrown away when they fail.
Most variation in size of sump pit diameter required. Submersible pumps can fit into a sump pit as small as 9 inches and may require a pit as wide as 18 inches when the tether float is used. Electronic level controllers require the least amount of room. Vertical floats required less room that a tether and do not get caught on the basin as easily.
Most float-switch options. Here are some of the options: tether float, vertical float, diaphragm, electronic level controller, variable level piggyback. The float-switch is the first thing that fails on a sump pump. They usually need to be replaced after 2 to 4 years. You need a wide pit to use a tether float switch. Though electronic level switch controller require the least amount of space, their operation is affected by the presence of calcium carbonate in the water.
Most variation in price. Thermoplastic costs under $100. Bronze costs over $600. The greater the horse power the greater the cost. Pumps with all cast iron parts are more costly.