Technical Terms (or is it alphabet soup?)

In order to compare different sump pumps, there are a few technical terms that you need to understand. This page does not cover every technical term, but it describes the most important ones

GPM = Gallons Per Minute
. It's close cousin is the GPH, or Gallons Per HOUR. Obviously, 1 GPM = 60 GPH. This is the main specification that tells you how much water a particular pump can remove in a given amount of time. Generally, more is better – a pump with a higher GPM rating can remove water faster than one with a lower rating. The number of GPMs a pump can remove has to do with its design and construction, how large and efficient the motor is, etc. The best pumps remove the most GPMs using the least amount of electricity...

LIFT or HEAD PRESSURE or FEET OF HEAD or STATIC HEAD: The number of GPMs a pump can remove is directly affected by HOW HIGH THE PUMP MUST LIFT THE WATER TO GET IT OUT OF THE HOUSE. All pump manufacturers test their pumps and publish a "pump curve" or "flow chart" that details how many GPMs the pump will remove at a given amount of LIFT. Lift is measured from the bottom of the sump basin to the highest point in the piping that the water must be raised in order to get it to flow out of the house. In a typical basement, 10' lift is a pretty good average figure.

An example of the pump curve for our popular S3 series pumps is shown below:


Using this chart, you can tell that our S3033 (blue line) will pump approximately 50 GPM at 10 feet of lift (start at the 10 foot mark on the left of the chart – it intersects the blue at approximately 50 GPM, about halfway between 40 & 60 on the bottom scale). Note that the exact same pump can pump more than 60 GPM at zero feet of lift, while at 15 feet of lift it only pumps 40 GPM.

Be careful when comparing GPM numbers between different companies and pump brands. We have noticed that some of our competitors quote GPMs at lifts less than 10 feet. They do this in order to inflate the GPM numbers and make their pumps appear to be higher capacity than they actually are. We always quote GPM numbers at 10 feet of lift! Comparing GPMs at different lifts is like comparing apples to oranges...

Another important thing to know about LIFT is that it's not unlimited – every pump has its "shutoff point", which is the maximum height it can pump to. The shutoff point is the height at which the pump will remove ZERO GPMs. If you have a basement with high ceilings, you should be careful to choose a pump that will provide adequate GPMs at your actual lift.

HP = Horsepower. Horsepower is, as you may have guessed, an old term that is a unit of POWER. Power is defined as how much work can be done in a given amount of time. Without going into excruciating detail, suffice to say that in general, the higher the HP rating of a pump, the more water it can remove (i.e. the higher the GPM). Sump pumps are available in a range of HPs; in the vast majority of cases sump pumps are either 1/3 HP or 1/2 HP. However, depending on the quality and efficiency of the pump, there are some 1/3 HP pumps with a HIGHER GPM RATING than some 1/2 HP models. We recommend comparing pumps based on GPM ratings (at 10' lift!), rather than worrying too much about HP.

AMPS or AMP DRAW: An "Amp" is a unit of measure of electricity flow or current (it's the electrical equivalent to GPM). The more Amps a pump draws, the more electrical energy it is using. The lower the Amp draw, the less electricity. The more energy efficient a pump is, the more GPMs it can remove at a given Amp draw. The most GPMs using the least Amps is what we're looking for. The PHCC Pro Series of pumps are excellent at pumping lots of water (high GPMs) using the least amount of electricity possible (low Amps). Not only do they remove a lot of water, they use less electricity to do so. You save money AND energy!