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Basic Water Systems Diagram

If you’re used to being on a city water supply, setting up an independent water system for the first time may seem like a daunting task. This diagram explains the all the parts of a variety of water systems. When you scroll your mouse over any labeled component, a text box will pop up on the right-hand side of the page, with an explanation of what each item does, and how it works with the rest of the system. (Apologies to mobile visitors, but this page requires a large screen.)

AC Power Source

Well pumps that run on AC power are the most common kind, although not the most efficient. However, if your entire home’s electrical system is designed for AC appliances, it may be more economical to use an AC pump than to install a separate DC electrical circuit just to power your water system.

AC water systems with demand pumps (which only switch on when water is being used) are also the simplest to set up, since a water holding tank is not necessary.
Battery Bank

If you have a large enough battery bank to support a demand pump (which only switches on when water is being used), many DC pumps operate more efficiently than AC models.

Having a large enough battery bank to operate a well/water pump off a battery power allows you to build the simplest, most efficient water system. The only components you will need (after the battery bank and power source) are a DC pump, pressure switch (if the pump does not include one), and a pressure tank.
Submersible Demand Pump

A submersible demand pump is designed to pump water up out of a well more than 20 feet deep, only pumping when water is actually being used. Submersible pumps are engineered for varying water depths, so make sure the model you choose is matched not only to your power supply’s voltage, but also to the depth of your well.

Any type of demand pump must be used with a constantly-available power source, whether that means you’re using it in a grid-connected home, or with a large enough battery bank that it won’t drain all your available power. The pump will either have an on-board pressure switch or use an external one, will start pumping when system water pressure drops below the switch set-point, and will shut off when a set pressure is reached.

One advantage of using a demand pump is that you don’t need a water holding tank as part of your water system (unless your well doesn’t have enough GPM capacity to meet your peak water needs).
Surface Demand Pump

A surface demand pump is designed to pump water out of a shallow well (20 feet or less) or a surface water source such as a pond, only pumping when water is actually being used. Surface pumps cannot lift water very far, but they are good at pushing water uphill. If your well or pond is at the bottom of a hill, and your house is at the top, a surface pump will serve you well.

Any type of demand pump must be used with a constantly-available power source, whether that means you’re using it in a grid-connected home, or with a large enough battery bank that it won’t drain all your available power. The pump will either have an on-board pressure switch or use an external one, will start pumping when system water pressure drops below the switch set-point, and will shut off when a set pressure is reached.

One advantage of using a demand pump is that you don’t need a water holding tank as part of your water system (unless your well doesn’t have enough GPM capacity to meet your peak water needs).
Pressure Switch

NOTE: If your water pump has a built-in pressure switch, you will not need to install an external one.

A pressure switch acts as an on/off switch for your water pump. It is set to a specific cut-in pressure, which turns the pump on when the water pressure in your pipes (or pressure tank) drops past a certain point (usually ~30psi). It is also set to a cut-off pressure, so it stops pumping when the water pressure in your system reaches it’s cut-off level (usually ~40-50psi). This means the pump will kick on after water has been running for a short time, and it will keep pumping for a short time after the water has been shut off.
Pressure Tank

Many water pumps work best when used with a pressure tank in the water line after the pump. The pressure tank will reduce pump cycling (switching on and off), by regulating water pressure in the system. The less your pump needs to cycle on and off, the less wear and tear it suffers during normal use. The more water you normall use, the larger your pressure tank should be.

A pressure tank has a hard outer shell, with a rubber air bladder inside. The space between the shell and bladder is pumped full of air to create pressure on the water inside the bladder. This creates a reservoir of pressurized water that can be delivered to your faucets without the pump needing to turn on immediately. The water pressure can be adjusted by increasing or decreasing the amount of air inside the shell.
Solar Panels

If you are building an off-grid water system, and your location gets enough sun exposure, a solar array is the easiest way to power your water pump. Solar panels are very durable, easily lasting 20-30 years under normal use, and require no routine maintenance.

A solar panel will send power to your pump whenever the sun is shining, which will keep it running until your holding tank is full. If you make sure the holding tank is large enough that you won’t run out of water when the weather gets cloudy, your solar water system should provide years of hassle-free service.
DC Fuse or Circuit Breaker

DC fuses or circuit breakers protect system components from damaging electrical current surges. A fuse or a breaker provides the same protection, but fuses need to be replaced every time they overload, while a circuit breaker can be reset. Fuses are initially more expensive, but over time a circuit breaker may save money.

The fuse or breaker must be rated for the correct DC voltage, and the maximum amperage the circuit will normally carry. All circuit breakers and fuses should be UL listed, and have insulating protective covers.
Solar Pump Control

If your solar well pump doesn’t include built-in control functions, you will need a solar pump control to regulate the current coming from your solar panel or array. A solar pump controller will optimize the operation of your pump, and in the case of Linear Current Booster controls, help the pump operate more effectively in lower light conditions.
Wind Turbine

Wind turbines can be an excellent source of water system power, if your location gets sufficient wind. Most turbines require a wind speed of 10 MPH or greater to begin generating power. Check your annual wind speed averages (and maximum wind speed) to make sure you choose the right wind turbine for your system.

While modern wind turbines are designed to be low maintenance, they can be damaged by excessive wind speeds, or ice build up on the blades. If you live in an area with frequent inclement weather, install your turbine in an easily accessible location, for ease of maintenance.
Lightning Arrestor

Wind turbines are most often mounted on tall aluminum towers, to give them the best possible wind exposure. Lightning arrestors protect your water system components from damage, in the event that your turbine tower attracts a lightning strike.
Wind Pump Controller

There are a number of variables when using a wind turbine to power a water pump. Wind turbines produce AC power, and an AC-DC current rectifier must be used if the turbine will be sending power to a DC load.

If the wind turbine has a built-in current rectifier, it will work with a DC pump fairly easily. Your pump controller will simply regulate the current going to the pump, and divert power to your diversion load when your holding tank is full. If your turbine does NOT have a built-in rectifier, it will work fairly easily with an AC pump. Again, the controller will simply be regulating or diverting the current.

If you have an un-rectified wind turbine and you need to power a DC pump, you will either need an external rectifier between your turbine and your DC pump controller, or a controller with an integral rectifier.
Diversion Load

When your water tank is full, and the float switch turns off your pump, your wind turbine will still be producing power if the wind is blowing. Since the turbine can be damaged by not having an electrical load to send power to, the controller needs a secondary diversion load to send excess power to.

A diversion load can be as simple as a large resistor which releases excess current as heat (although these need to be installed in fire-safe locations). Other options include using diversion current to run an auxiliary ventilation or heating system for your well house or power shed. DC-powered water heater elements are also a practical option for using diversion power.

NOTE: Always make sure that your chosen diversion load is sized to handle the maximum amount of power your wind turbine is capable of producing!
DC Fuse or Circuit Breaker

DC fuses or circuit breakers protect system components from damaging electrical current surges. A fuse or a breaker provides the same protection, but fuses need to be replaced every time they overload, while a circuit breaker can be reset. Fuses are initially more expensive, but over time a circuit breaker may save money.

The fuse or breaker must be rated for the correct DC voltage, and the maximum amperage the circuit will normally carry. All circuit breakers and fuses should be UL listed, and have insulating protective covers.
Surface Solar Pump

A surface solar (or wind) powered pump is designed to pump water out of a shallow well (20 feet or less) or a surface water source such as a pond, pumping water into a holding tank whenever the solar panels or wind turbine are producing power. Surface pumps cannot lift water very far, but they are good at pushing water uphill. If your well or pond is at the bottom of a hill, and your house is at the top, a surface pump will serve you well.

Solar/wind powered pumps are designed to work directly with a solar panel array or wind turbine, without needing a special pump controller. Other pumps can also be used with renewable power sources, if an appropriate controller is used with them. A solar/wind pump system will run the pump at varying speeds, depending on the amount of power being delivered at any given time.

Because you can’t guarantee when the weather will cooperate, this kind of water system needs a holding tank for the pump to pump water to. The pump is turned on and off by a float switch in the holding tank, so it won’t overflow.
Submersible Solar Pump

A submersible solar/wind powered pump is designed to pump water up out of a well more than 20 feet deep, pumping water into a holding tank whenever the solar panels or wind turbine is producing power. Submersible pumps are engineered for varying water depths, so make sure the model you choose is matched not only to your power supply’s voltage, but also to the depth of your well.

Solar/wind powered pumps are designed to work directly with a solar panel array or wind turbine, without needing a special pump controller. Other pumps can also be used with renewable power sources, if an appropriate controller is used with them. A solar/wind pump system will run the pump at varying speeds, depending on the amount of power being delivered at any given time.

Because you can’t guarantee when the weather will cooperate, this kind of water system needs a holding tank for the pump to pump water to. The pump is turned on and off by a float switch in the holding tank, so it won’t overflow.
Float Switch

The float switch is a very simple on/off control for your solar/wind powered pump. The switch works similarly to an upside-down light switch, which closes a circuit (turns on) in the down position, and opens the circuit (turns off) when it lifts up.

The switch works because of an arm with a foam or plastic float attached. This arm drops as the water level in your holding tank goes down, until it closes the circuit and turns the water pump on. As the water level goes back up, the float arm rises until it turns the switch (and the water pump) off again.
Water Holding Tank

A holding tank is useful in a couple of types of water systems:

Renewable energy-powered pump systems, where your water flow is determined by the weather rather than by your usage.

Low-volume well systems, where your well does not produce as much water as your household uses during peak times.

For a solar/wind powered well, your holding tank should hold about a week’s worth of water, so you will not run out during extended periods of cloudy weather or calm winds. For a low-flow well, it depends on your usage and well production. One or two day’s capacity should be enough to ensure your well doesn’t run dry in the middle of a shower or a load of laundry.
Pressure Booster Pump

Pressure booster pumps are available in both AC and DC powered models, and generally come in one of two types:

Compact stand-alone models with built-in pressure switches. These are perfect for RVs, boats, or tiny houses, because you won’t need to find room to install a pressure tank.

Simple models designed to be used with external pressure tanks, which may or may not include a pressure switch. These are good for more traditional installation locations.

If you have a remote install location, and you rely solely on an off-grid power system, it may be more economical to build a water tower than to have a booster pump using additional electricity. In this case, installing your holding tank on a 100 foot support tower will create 40 psi of water pressure at ground level. However, if you have excess capacity in your power system, or you have grid power available, pressure booster pumps are definitely the easier option.
Pressure Switch

NOTE: If your water pump has a built-in pressure switch, you will not need to install an external one.

A pressure switch acts as an on/off switch for your water pump. It is set to a specific cut-in pressure, which turns the pump on when the water pressure in your pipes (or pressure tank) drops past a certain point (usually ~30psi). It is also set to a cut-off pressure, so it stops pumping when the water pressure in your system reaches it’s cut-off level (usually ~40-50psi). This means the pump will kick on after water has been running for a short time, and it will keep pumping for a short time after the water has been shut off.
Pressure Tank

Many water pumps work best when used with a pressure tank in the water line after the pump. The pressure tank will reduce pump cycling (switching on and off), by regulating water pressure in the system. The less your pump needs to cycle on and off, the less wear and tear it suffers during normal use. The more water you normall use, the larger your pressure tank should be.

A pressure tank has a hard outer shell, with a rubber air bladder inside. The space between the shell and bladder is pumped full of air to create pressure on the water inside the bladder. This creates a reservoir of pressurized water that can be delivered to your faucets without the pump needing to turn on immediately. The water pressure can be adjusted by increasing or decreasing the amount of air inside the shell.
Off-Grid Water System

Solar or wind powered water pumping systems are the water system of choice for remote off-grid locations. Livestock watering stations in remote ranches have used wind-powered pumping systems for years, and remote villages in the developing world install solar and wind powered wells as an alternative to walking for miles to gather water from surface water sources. Direct solar/wind systems are the most practical type of water system for most off-grid locations.

Solar powered pumps are engineered to run at variable speed, dependent on how much power is available at any given moment. This pump fills a water holding tank which your household use draws from, much the same way your household power needs are supplied by a battery bank, which “fills up” and stores power as your renewable energy sources are able to produce it.
On-Demand Water System

Because the US has a very far-reaching electrical grid, by far the most common water systems used in this country are on-demand systems run with utility power. The simplest way to set up a grid connected water system is to use a variable speed AC-powered pump, with a built-in pressure switch, so you don’t even need a pressure tank. The most common way to set up an AC-powered demand water system is a pump with built-in pressure switch, and a pressure tank after the pump.

If you have a large enough renewable energy supply to run a DC demand pump, that could be an option for an off-grid home, however we still recommended using a holding tank system. In the event of extended periods of low power production, or some kind of storm damage to your power system, an adequately sized holding tank will ensure you don’t run out of water.
Wiring

Always make sure your electrical wiring is rated for the type of current your system is using. Standard 110AC household wiring is the easiest to find, but we carry a wide range of DC rated wire and cable for your system needs.

If you set up a water system using a mix of AC and DC components, make sure all your electrical wiring is clearly marked as to which is which. If you are at all in doubt about wiring issues, the safest idea is to have a licensed electrician install your electrical wiring for you, making sure it is designed to the specifications you need.
Water Lines

Water lines are most commonly run with either CPVC or PEX pipe. PEX pipe is preferable in a cold climate, because its flexibility allows it to resist freezing without as much risk of breaking. If you live in a warm climate where freezing is rare, CPVC will work fine, and costs less to install.

Regardless of which kind of pipe you decide to use for your water lines, make sure it is large enough diameter for your desired water flow.