Switch - Does number of pumping cycles affect 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.
Pit size - Does size affect pump options?
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.