A shimmering pool on a hot day is the epitome of backyard bliss. Homeowners meticulously focus on the filter, the pump, the chemistry, and the cleaning. Yet, there is a small, often overlooked component that plays a disproportionately critical role in the health, efficiency, and longevity of the entire aquatic system: the pool spigots. These unassuming fixtures, also commonly referred to as pool drain plugs or air relief valves depending on their location, are far more than simple caps. They are vital gatekeepers, managing pressure, facilitating maintenance, and protecting your pool's intricate plumbing from catastrophic damage. Understanding their function, types, and care is essential for any responsible pool owner.

The Critical Functions of Pool Spigots

At first glance, a pool spigot might seem like a basic plug, but its job description is complex and essential. Its primary functions are centered around pressure management, water direction, and system protection.

• Pressure Regulation and Air Relief: Inside your pool's filter tank, particularly a sand or D.E. filter, air can become trapped during the initial priming process or from normal operation. This air pocket reduces the filter's efficiency and can cause unnecessary strain on the pump. The air relief valve, a specialized type of pool spigot on top of the filter, is designed to release this trapped air. You open it manually when starting the system until a steady stream of water appears, signifying all air has been purged. This simple act ensures optimal filtration and prevents potential damage from airlocks.
• Facilitating Winterization: Perhaps the most crucial role of drain plugs is in protecting your pool during the off-season. When winterizing a pool, the number one rule is to remove all water from the plumbing lines, pumps, filters, and heaters to prevent freezing. Expanding ice can crack PVC pipes, split filter tanks, and destroy expensive equipment. The various pool spigots located on the pump housing, filter multiport valve, heater, and sometimes the filter tank itself are the designated drainage points. By removing these plugs, you allow water to completely drain out, leaving the equipment dry and safe from freeze damage.
• Access for Maintenance and Cleaning: Certain pool spigots provide direct access to internal components. For example, removing a plug from the pump strainer basket housing can help flush out debris. In some filter systems, plugs provide an access point for internal cleaning or for adding filter media. They are the entry points for servicing the hidden parts of your pool's circulatory system.
• Backup Drainage and Flow Control: On some pool systems, a pool spigot may be installed on a pipe to act as a manual drain point for lowering the pool water level or for completely draining the pool if necessary, serving as a secondary outlet beyond the main drain.

Identifying the Different Types of Pool Spigots

Not all pool spigots are created equal. They vary in size, thread type, and material, and are located in different parts of the system. Knowing where to find them and what they look like is the first step in proper maintenance.

• Pump Basket Housing Plugs: These are typically the most common pool spigots a homeowner will interact with. They are found on the front of the pump strainer basket lid or on the bottom of the pump housing itself. They are usually made of durable plastic or brass and are removed to drain water from the pump for winterizing. It is critically important to ensure the O-ring or gasket on these plugs is in good condition to prevent air suction leaks during operation.
• Filter Tank Plugs: Sand and D.E. filter tanks often have one or more pool spigots located at the bottom. These are used to completely drain the filter tank for deep cleaning, media replacement, or winterization. They are generally larger and may require a wrench to loosen. The multiport valve on top of the filter also has a dedicated air relief valve, which is a threaded pool spigot that you manually screw open and closed.
• Heater Plugs: Pool heaters, especially those with copper headers, are extremely vulnerable to freeze damage. They are equipped with their own set of pool spigots, often on the front and back of the unit on the plumbing manifolds. These must be removed during winterization to ensure every drop of water is evacuated from the heater's internal tubes.
• In-Line Pipe Plugs: Some pool plumbing may include threaded plugs installed directly into pipes for future access or as auxiliary drain points. These can be made of PVC, brass, or stainless steel.

Essential Maintenance and Troubleshooting for Your Pool Spigots

The maintenance of pool spigots is simple but non-negotiable. Neglect can lead to leaks, air intake problems, and costly repairs.

• The Seasonal Ritual: Removal and Storage: During winterization, every single pool spigot on every piece of equipment must be removed. As you remove each one, place it in a zip-top bag and label it. For example, "Pump Drain," "Filter Drain," "Heater Left Side." This prevents confusion and loss during reassembly in the spring. Store the bag in a safe place with your other pool chemicals and supplies.
• Inspecting and Replacing O-Rings: The most common issue associated with pool spigots is leaking, which is almost always due to a degraded O-ring. Before reinstalling plugs in the spring, carefully inspect the rubber O-ring for any signs of cracking, brittleness, or flattening. A small tube of pool lubricant is an essential tool; applying a light coat to the O-ring before threading the plug back in will ensure a perfect seal, prevent cross-threading, and make removal easier the following year.
• Dealing with Stuck or Stripped Plugs: A pool spigot that has been overtightened or has succumbed to mineral deposits can become stuck. Never use excessive force with a wrench, as this can easily strip the plastic threads or crack the housing. Apply a penetrating lubricant designed for PVC and allow it to sit for several minutes. Use a well-fitted wrench and apply steady, gradual pressure. If the plug is stripped, it must be replaced. Keeping a small spare parts kit with common-sized plugs and O-rings is a wise investment for any pool owner.
• Preventing Leaks and Air Suction: If you notice air bubbles coming from your return jets after opening the pool for the season, a leaky O-ring on a pump basket pool spigot is a prime suspect. The vacuum created by the pump can suck air through these tiny gaps, reducing pump efficiency and potentially leading to premature pump seal failure.