A flooded basement is no fun. Who wants to find themselves wading in ankle deep water, squishing atop a carpet that will have to be torn up and thrown away? Even when the rain stops the problems keep on coming. In olden days, it was tough to prevent water in the cellar, and there was nothing to be done about an unwanted swamp in your lower level but to haul the water out bucket by bucket and to resolve never to keep anything of value down there again.
Somewhere along the line, however, folks figured out they could clear water from a basement and keep it from wreaking havoc by using a sump pump. Read on for some information about how one of these gadgets can save you from weeks of miserable cleanup work and an unpleasant interaction with your insurance company.
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What is a sump pump?
As the name implies, a sump pump is a pump that pumps water out of a sump. The English word sump derives from the German sumpf, which is a marsh or swamp. You probably don’t have a swamp in your basement, at least not most of the time, but it’s highly possible that you have a sump. It’s a small pit or depression in the floor of a basement that collects water. The house is equipped with a draining system that captures excess ground water and directs in into the sump.
If there’s a working sump pump, when the water in the sump reaches a problem level, the sump pump kicks on and discharges the water to the outside through a pipe. Ideally the water level never reaches the top of the sump, and you never experience the aggravating damage that can be done by standing water.
If you have a sump, you probably have a sump pump. If you don’t, you need to install one, and do it now, before your basement sump overflows. And even if you already own a sump pump, they don’t last forever. A normal pump lifespan, depending on the type of pump and how often it’s called on to remove water, can be anything from 5 to 30 years.
If you’re not sure of your sump pump, test it with a large bucket of water. Slowly pour the water into the sump until the unit starts working. There will be a switch in the form of a float or a collar that starts the pump when water reaches that level. Sometimes it’s an electronic sensor. Continue to fill the sump past the trigger level then let the water recede. When the water drops below the switch the pump should shut off.
Even if your pump is working, inspect it for rust or for cracks that could be the start of leaks. These can eventually ruin the motor, particularly if your pump is the type that sits under water inside of the sump.
When the waters start to rise, whether you’re at home or away, you want to be certain that your pump will kick on and do its job. Inspection and testing is the best way to ensure this.
Types of sump pumps
The main pump, the one called on to do most of the work most of the time, is called a primary sump pump. It runs on AC and is plugged or wired into your home’s electrical system. Because of that, it will work only as long as you have power. There are also backup sump pumps to take over when the primary pump is overwhelmed or incapacitated.
Primary sump pumps
There are two types of primary sump pumps, submersible and pedestal. One sits down inside the sump and the other stands above it. Which is better? It depends: both have their advantages and disadvantages and situations in which they are the more suitable choice.
Submersible Sump Pumps
A submersible sump pump is installed on the floor of the sump. Its motor is protected so that it will continue to operate and not be damaged even when it’s underwater. Submersibles tend to be the more powerful pumps. Because they’re submerged when they’re working, they’re quieter, and the water make them less susceptible to overheating. They’re also out of the way where you and your visitors don’t have to look at them them.
You can spend a few extra dollars and bring home a heavy duty submersible sump pump that will handle everything you can throw at it for years, or you might opt for a less expensive model.
Pedestal Sump Pumps
A pedestal pump is tall and thin, and only the base of the pump gets covered with water. The motor sits high and dry, mounted near the top of the unit. Because of this, the motors generally last longer. On the other hand, pedestal pumps are more visible and might present a temptation to children who decide to use them as a hobby horse or other plaything the pumps are not made for. If you don’t mind looking at your pump, and you like the longevity and the lower price, a pedestal sump pump may be just fine for you.
Submersible or Pedestal? Which Should I Choose?
Whether you install a submersible or pedestal primary pump, there are general considerations and features you should think about. At the top of the list is how frequently you expect your pump to be used. If you live in an area that is known for heavy rainfall and flooding, you need a pump that will push a large volume of water in a hurry. You don’t want a pump that will fall short when you need it most.
Flow rate is the most important single factor to tell how much adversity a pump can handle. It’s expressed in gallons per hour (GPH). The top pumps are rated to push 4,000 – 5,000 GPH out of your basement. Bear in mind that these ratings assume the water is being pumped though a horizontal pipe, which is seldom the case in real life. Generally the water has to go up and out. Many manufacturers will also give you a GPH number that assumes a 10 foot rise in the discharge pipe. This more realistic number may be only two-thirds to three-quarters of the max.
In general, submersible pumps have stronger flow rates than pedestals.
Durability. Because pedestal motors are never covered in water, they last longer. The average life span of a pedestal pump is 25-30 years as opposed to 5-10 for a submersible. Even between various models of submersibles there are differences. They are warrantied for as many as five years or as little as one. Housing construction is important. Look for cast iron or stainless steel as opposed to plastic. Susceptibility to leaks is huge in submersible pump longevity.
Horsepower is important to both flow rate and durability. Pump motors run from one-quarter HP up to one HP. If you anticipate having to push a lot of water over the life of the pump, select a more powerful machine.
Handling Debris. Submersible pumps, since they sit under water, can filter out debris before the water gets pumped. Pumps vary in how large a solid they can successfully pass through their system. Some can push though objects as large as half an inch in diameter.
Noise. Submersibles are quieter, but even between pedestal models some units are quieter than others.
Ease of installation varies widely. In general pedestals are easier to install but there are exceptions. Some units are pre-assembled and some aren’t. There are pumps that anyone can install in an hour, and others that require a competent DIYer or a professional.
Overheating is less likely with submersibles, which are naturally cooled by the water that surrounds them.
Ease of maintenance. Pedestals win this one handily, as the motor is up where you can see it and easily get to it.
Appearance. Many people don’t like the fact the pedestals are visible and somewhat unsightly. On the other hand, submersibles are out of sight.
Basin or sump size. Some submersibles won’t fit in a small sump.
Switch type. Float switches have floats that ride on the water. The unit comes on when they rise and shuts off when they fall. Electronic switches have a top and bottom sensor that tell the pump to stop or start when they detect water. Floats can be effected by debris buildup, but electronic sensors can get blocked over time by minerals in the water.
Cost. As you would expect, the more powerful and durable sump pumps cost more. Submersibles are generally more expensive than pedestals.
Most submersible sump pumps have an advantage in power, flow rate, appearance, ability to deal with debris and solids, noise and engine cooling. Pedestals tend to last longer, cost less and be easier to install and maintain. In some cases sump size may make a pedestal sump pump the only choice.
If you in an area that is prone to flooding, and you can expect to have to deal with large volumes of water on a regular basis, a submersible pump, with its superiority in power and flow rate, is going to be the safer choice. The additional initial cost and the reduced longevity may be worth putting up with to give you peace of mind.
Do I need a sump pump backup system?
Is a backup sump pump necessary? Unless you live in a world where the power never goes out, yes, it is. Flooding is often caused by storms, and storms can be accompanied by high winds, gusts and downed power lines. If you have the most expensive and powerful primary sump pump on the market but no battery backup sump pump, you may find yourself with an expensive piece of equipment that just sits there and ignores you when you most want it to get to work.
Battery Backup Sump Pump
First, a caution about the name. Make sure you buy a battery backup sump pump with the word battery in it. Some manufacturers will advertise a backup sump pump that runs on AC. That’s fine if you want your primary pump to have a little assistance when the power is on, but of no use at all when the lights go off. You need a true battery backup for an existing sump pump.
Some primary sump pumps have battery backup built into them. If you don’t have one of those you’ll want a separate battery backup pump. These are submersible pumps that discharge into the same pipe as the primary pump. They remain charged as long as the power is on and provide hours of pumping when the power go out.
You can’t expect a battery operated unit to provide quite the same oomph your primary pump does, but many of these are no slouches. Some have motors as powerful as one-half horsepower and pump at GPH ratings not that far below the primaries.
If you have a small sump you may be limited in the size of battery backup sump pump you can install if you already have a primary pump in that sump. You may need to choose a combo unit that has both AC and emergency battery power.
If price is not your primary focus a do it all combo submersible and backup pump is available. Or you can opt with a battery-only pump made to be used in conjunction with your AC submersible.
What battery backup sump pump features should I look for?
It’s nice to have a pump that will display the status of the battery and how much battery time is left. Some battery backups alert you when they come on, by connecting them to an alarm system or an autodialer. Some are “smat pumps” that will push alerts and information over wifi.
While a battery back sump pump won’t give you the HP or GPH of a top primary pump, the bigger these numbers, the more robust your pump will be. Take a look at battery life and charging speed. Battery backup sump pumps that come pre-assembled are easier to install.
Water Powered Backup Sump Pump
What happens if the power goes out, your primary sump pump stops pumping and you run the battery on your backup pump until it’s all gone as well? That’s where a water powered backup sump pump can be a homesaver.
This kind of pump runs off of a municipal water supply. It may seem a little strange to bring even more water into your house when you already have too much, but here’s how the water powered pump works.
The water pump consists of a pipe running across your basement’s ceiling and discharging outdoors. Attached to it is a vertical pipe from your sump. When the pump is triggered a valve is opened and municipal water runs into the pipe. As the water runs through this narrow pipe, the pressure increases to the point where it draws water up the vertical pipe, much like sucking up soda pop with a straw. Amazingly, some of these pumps pull out water at a 1:2 ratio, meaning they remove two gallons of basement water for every gallon of city water they use.
Because of the pressure requirement, this will only work with municipal water. You can’t run a water powered pump off well water. There needs to be pressure of 20-40 pounds per square inch. You can ask your locality what the pressure is or buy a tool to measure it at a hardware store.
Of course you’ll have to pay for the city water you use, but a big water bill is a lot better than the bills flooding can create. Like battery backups, these won’t give you the flow rate of top primary pumps, but some will discharge over 1,000 GPH.
Other Dos and Don’ts
Here are a few tips to help ensure your pump is healthy and ready to do what you bought it for.
- Test your pump at least once a year by filling the sump from a water bucket.
- Only use the pump for its intended purpose, i.e., to push clean ground water out of a sump. Don’t run water from a water softener or washing machine through the system. Also, your pump isn’t designed to operate the water feature in your goldfish pond.
- While it’s possible to plug a sump pump into any outlet, it’s best to have a ground-fault circuit interrupted (GFCI) with a dedicated circuit breaker. An electrician can install one of these for you. Long extension cords and shared outlets are a poor idea. The possible drop in voltage can take months or years off the life of your pump.
- Be sure your discharge line has a check valve. That’s a flap that prevents water from running back down into the pump after the machine shuts off. These are susceptible to mineral buildup so it’s a good idea to replace it if you’re replacing your old pump.