Unions and Fittings

(86 products)

Pool unions and fittings are the connectors that hold your plumbing system together and make equipment serviceability possible. From union connectors that allow pumps and filters to be removed without cutting pipe, to couplings, elbows, and tees that route water through your equipment pad, EZ Pools carries the fittings you need for repairs and new installations. Browse our selection below and get free shipping on qualifying orders.

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CMP 1.5 inch PVC Flush Union

Pool Unions and Fittings Explained

Fittings are the structural connectors of your pool plumbing system. Every bend, branch, and straight connection in your equipment pad relies on some type of fitting to keep water moving in the right direction. The most common types are couplings (straight connections between two pipe sections), elbows (for direction changes), tees (for splitting a line), and reducers (for transitioning between pipe sizes). Most residential pool plumbing uses schedule 40 PVC fittings, though schedule 80 is available for higher-pressure applications.

Unions are a specific and critical type of fitting designed to be disconnected and reconnected without cutting pipe. A union consists of two threaded halves with a slip socket on each end and a union nut that draws them together. When you need to remove a pump, heater, or filter for service, the union nut is unscrewed, the equipment slides free, and everything reassembles the same way. Without unions at equipment connections, any removal means cutting and regluing pipe, which adds time and cost to every service call.

Most pool equipment ships with or is designed around 1.5 inch or 2 inch union connections. If you are adding a union to an existing glued connection, you will need to cut the pipe and install union adapters on both sides. It is straightforward work but worth doing once to avoid cutting pipe every time the equipment needs attention.

Choosing the Right Pool Fittings

The most important factor when selecting pool fittings is pipe size. Confirm whether your system runs 1.5 inch or 2 inch pipe before ordering, and check both the pipe diameter and the fitting socket size since they need to match exactly. Reducers and adapter fittings are available if you are transitioning between sizes, but keeping your plumbing consistent wherever possible simplifies future repairs.

For unions specifically, make sure the union matches both the pipe size and the thread standard of your equipment. Most pool equipment uses standard PVC union threads, but mismatched unions will not seal properly even if they appear to fit. When replacing a union, bring the old one with you or note the brand and size to make sure you are ordering a compatible replacement. Unions from the same manufacturer as your valve or equipment are the safest bet for a leak-free connection.

Schedule 40 PVC is the standard for residential pool fittings and handles typical pool plumbing pressures without issue. If you are working on a commercial installation or a system with unusually high operating pressure, schedule 80 fittings offer thicker walls and higher ratings. EZ Pools carries unions and fittings in both schedules and in the common residential sizes to cover most repair and installation scenarios.

IntelliChlor Cell Unions - 2 Pack, 520595

Frequently Asked Questions

What is a pool union and why do I need one?
A pool union is a two-piece threaded fitting that allows a plumbing connection to be broken and reassembled without cutting pipe. Unions are installed at equipment connections so that pumps, filters, and heaters can be removed for service or replacement without replumbing the entire line. If your equipment does not already have unions, adding them is one of the most practical upgrades you can make to your equipment pad.
What size pool fittings do I need?
Most residential pool plumbing uses 1.5 inch or 2 inch PVC fittings. Measure your existing pipe diameter or check the markings on your current fittings to confirm the correct size. If you are transitioning between two different pipe sizes, you will need a reducer or adapter fitting to bridge the difference.
Can I mix brands when replacing pool unions?
It depends. Most pool unions use a standard PVC thread pattern and will mate correctly with unions from other brands of the same size. However, some manufacturers use proprietary thread profiles or sizing, so mixing brands can result in a poor seal. When in doubt, replace both halves of the union at the same time and use the same brand throughout the connection.
What is the difference between schedule 40 and schedule 80 pool fittings?
Schedule 40 and schedule 80 refer to the wall thickness of the PVC. Schedule 80 has thicker walls and a higher pressure rating than schedule 40. For most residential pools, schedule 40 fittings are sufficient. Schedule 80 is typically used in commercial installations or systems with higher operating pressures. The two schedules use the same outer diameter, so they can be combined in the same plumbing run.
What other pool plumbing parts might I need along with fittings?
Depending on your project, you may also need ball valves for flow control, check valves to prevent backflow, or diverter valves to split flow between lines. Browse our full pool plumbing supplies section to find everything you need in one place.

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Shop Unions and Fittings

Shop our selection of pool unions and fittings and find the right connectors for your plumbing repair or installation. EZ Pools carries couplings, elbows, tees, union fittings, and more in standard residential sizes with free shipping on qualifying orders.

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