How Valves Work

How Valves Work

Pool valves are an essential part of a swimming pool's plumbing system, and they serve various functions to control the flow of water. They help you manage water circulation, divert water to different parts of the pool or pool equipment, and control the pool's operation. There are typically three main types of valves used in a pool system:

  1. Diverter Valves: Diverter valves are Premier Pool & Spa's preferred and recommended valve type as they are generally maintainable and repairable. (Can be taken apart and lubed, internals can be replaced) These valves have multiple ports or outlets that can be adjusted to send water to different destinations, allowing you to divert water to specific areas or equipment as needed. Diverter valves are commonly used to control the flow between the main drain, skimmer, and return lines, as well as various pool equipment such as pumps, heaters, and water features. Here's how diverter valves work and where they are typically used in pool systems:
    Two-Way Diverter Valves: These valves typically have one inlet and one outlet. This valve is Premier's most commonly installed valve, used in almost every installation.
    diverter valves and how they work
    Three-Way Diverter Valves: These valves typically have one inlet and two outlets. They are often used in the plumbing system to control the flow of water between the main drain and the skimmer(s). By adjusting the valve, you can determine whether water is drawn from the main drain, the skimmer(s), or a combination of both. This helps you balance the water intake from different parts of the pool. Premier Pool & Spa does not recommend using Three-Way Diverter Valves in this way. We highly recommend the main drain and skimmer(s) be plumbed in a header configuration with separate Two-Way Diverter Valves to allow for full on/off control of each suction line independently.
    Four-Way Diverter Valves: Four-way diverter valves have one inlet and three outlets. They are used to control the flow of water to various pool equipment, such as pumps, filters, heaters, and water features. By rotating the valve handle, you can direct water to the desired destination, which can be a single piece of equipment or a combination of multiple pieces of equipment.
  2. Slice/Gate Valves: Slice or Gate valves have a gate or wedge-shaped disc that moves perpendicular to the flow of water. When the valve is fully open, the gate is raised, allowing water to flow freely. When it's fully closed, the gate blocks the flow of water. Gate valves are commonly used to shut off the flow of water to specific parts of the pool system, such as pumps or filters. These types are rarely used on pools any longer and should be replaced with diverter valves when they are encountered.
    gate & slice valves

  3. Ball Valves: Ball valves have a spherical ball with a hole through it, which can be rotated to control the flow of water. When the handle is aligned with the pipe, the valve is open, allowing water to flow. When the handle is turned 90 degrees, the valve is closed, blocking the water flow. Ball valves are often used for on/off control of water flow in pool plumbing. These valves are generally not repairable and need to be replaced after a number of years. Pool installers generally use ball valves due to their inexpensive cost to the pool installer. If there is a ball valve on a main drain line and it does not seal when closing the pool for the season, your Premier Pool & Spa technician will have to cut the ball valve out of the plumbing to blow out the main drain and will plug the pipe leading to the main drain with a rubber plug.

  4. Multiport Valves: Multiport valves are specifically used in pool filters, particularly in sand and DE (diatomaceous earth) filters. They have several settings that allow you to direct water flow to various functions, such as filtering, backwashing, rinsing, and more. Multiport valves typically have six positions, including filter, backwash, rinse, waste, closed, and recirculate(bypass). These valves are used to manage the filtration and cleaning of the pool water. If your filter develops a leak at any point you can often use the recirculate(bypass/recirc) setting on your valve to bypass the filter, allowing you to heat and circulate your pool until the filter is repaired or replaced.

    backwash setting multiport valve

The specific functions of these valves in a pool system include:

  • Skimmer Valve(s): This valve controls the suction flow of water from the skimmer to the pump and filter system. You can adjust it to control the amount of water being drawn from the pool's surface. (Skimmer = rectangular hole with floating door and basket at the water line on the pool)

  • Main Drain Valve(s): The main drain valve controls the suction flow of water from the main drain(s) to the pump and filter system. You can adjust it to control the suction flow from the bottom of the pool. (Main Drain = the round cover(s)/suction line(s) that are in the very bottom of your pool)

  • Sump Valve: Some pools have a suction valve that stays off 99% of the time. This valve connects to a sump line that goes underneath the pool. This valve is opened anytime water is present in the ground under and around the outside of the pool structure. When the sump valve is opened the sump line may need to be primed (air sucked out of the line). After the sump line is primed and water is getting pulled out of the ground sump by the pool pump, the pump will need to be monitored, once the sump line starts pulling air again, the sump valve must be turned off.  
  • Return Valve(s): This valve controls the return flow of water from the filter system back to the pool. It allows you to control the direction and volume of water returning to the pool.

  • Waste Valve: In some pool systems, a waste valve is used to bypass the filter and send water directly to a waste line, useful for vacuuming or lowering the pool's water level.

  • Backwash Valve: In sand and DE filter systems, the multiport valve has a backwash setting, which reverses the flow through the filter to clean the filter media. (Turn pump off before moving multiport valve handle)

  • Rinse Valve: After backwashing, a rinse setting is used to settle the filter media before returning to the filter setting. (Turn pump off before moving multiport valve handle)

Properly maintaining and using these valves is essential to keep your pool in good condition and ensure effective water circulation and filtration. It's important to understand how each valve works and their respective functions to operate your pool equipment efficiently.