What is a swimming pool pump? It's the thing that makes the water move through the pool pipes and circulates the water.
Basically, a swimming pool pump circulates water through the pool. The water passes through a little basket (to remove any debris) before it gets to the actual spinning pump part. The water is actually pumped by having this impeller spin at high speeds. Water is pumped out. Sounds easy right? Maybe you could build one on your own? Hah, I wouldn't suggest it. This is an oversimplified explanation.
Keep in mind the difference between the pump and the motor. The pump is the large, tough plastic part that makes the water move, the motor is what powers it. Motors can go bad and there might be nothing at all wrong with the pump. I've seen a motor where someone had let an anthill grow and grow and it was actually starting to get into part of the motor (a powerful electric device). Eventually it got hot enough and the anthill got close enough and the motor was running (an electric device, remember) and the motor caught on fire.
The moral of the story is: keep debris away from your motor. There's another story about a guy who was spraying WD-40 on his motor as it was running. Don't do that either. There are limits to what WD-40 can fix.
What kind of pump do you need for your pool? Well, you'll need a horsepower rating that is appropriate for your pool size. You don't want to have the pump underpowered because then it won't circulate enough water to keep your pool clean.
Surprisingly, you don't want it overpowered either because then your pool might feel like a giant whirlpool. Don't worry, though, as your local pool company should be able to calculate a pool pump that is right for their size.
What if your local pool company doesn't have anyone that can calculate the right size? No worries, they'll probably just call up their supplier and ask. The larger pool product distributors have people who figure things out like this all the time.
My only recommendation about buying a pool pump is to ask for an energy efficient pump. Your pump is going to be running most of the year, and it's going to last for several years, so the cost of energy is going to add up over time. The energy efficient pumps cost a little more money initially, but the savings will add up over time, and you'll have a lower monthly energy bill.
Also, some of the energy efficient pumps are quieter than their less efficient counterparts. Do yourself a favor and go for the efficient version. If you're looking for a replacement for your broken pump, I'd recommend you order a replacement online. Just make sure it's the same one you already have.
This sums up the basics on pool pumps. Your local pool builder will undoubtedly have his preferences and likes on pool pumps, but now you should at least be able to talk intelligently with him.
