General Pump information by Zoeller Engineered Products


INFORMATION NEEDED TO PROPERLY SELECT A PUMP:
	1) VOLTAGE 2) WHAT IS BEING PUMPED? 3) HOW HIGH DO YOU HAVE TO PUMP VERTICALLY? 4) HOW FAR DO YOU HAVE TO PUMP HORIZONTALLY? 5) TYPE OF PIPE AND SIZE.
SIZING A SEWAGE PUMP:
	There are actually 3 ways to size a sewage pump. Each method will provide an estimate of peak flow conditions.
	1) FIXTURE UNIT CALCULATION
		This method uses the "Hunter Curves" for approximating water usage by a typical plumbing fixture. This is an acceptable way of estimating the pump flow requirement for residential and small commercial applications.
	2) LARGER CAPACITY SYSTEM CHART
		This is a derivation of the fixture unit method. It takes into consideration that in a high density environment, a ratio of plumbing fixture use can be applied to approximate peak flows. Method can be utilized for structures such as motels, apartment complexes, trailer parks, large office buildings and etc.
	3) POPULATION METHOD
		Method of calculating demand used by civil engineers when designing municipal sewage systems. A gallon per day usage pattern is established for each type of building structure. Then a peak factor is applied which is spread out over a 24 hour period. This method is used for homes and other residences whose sewage flows into a municipal sewage system. This method can only be used in those applications where a large basin is used.
Regardless of what your peak flow requirement is for a given application, the pump must always be able to provide a minimum velocity of 2 feet per second through the line. Line sizes with their accompanied minimum flow rates are as follows:

OTHER FACTORS CONCERNING PUMP SELECTION:

1) Total dynamic head (tdh) in feet is the total resistance in the piping network which you are pumping against. Do not select a pump if the tdh is less than the minimum point shown on its’ curve.
2) the pump selected must be capable of pumping to the highest vertical point in the system.
3) do not undersize the basin. If possible, always select a pump and basin assembly which will allow for at least a 30 second pump cycle.
4) air can interfere with the pump’s ability to work. Always drill a vent hole in the discharge line between the pump and check valve. In long horizontal runs of pipe, air relief valves may be required.

1.25" -	9 GPM	3" -	46 GPM
1.5" -	13 GPM	4" -	78 GPM
2" -	21 GPM	6" -	180 GPM