How a pool works, part by part.
Water leaves through the skimmer and main drain, passes the pump, filter and chiller in the plant room, and returns through the inlets. Most problems sit somewhere on that loop, or in the shell around it.
Skimmer
Draws surface water to the filter. Joints between skimmer and shell are a common leak point.
Specialists who work on this
- Leak detection
- Pipe repair
A teaching diagram. Real pools differ, and only an inspection tells you what is wrong.
Pool shell
The structure that holds the water: reinforced concrete, fibreglass or steel.
Waterproofing
The membrane between shell and finish. When it fails, water travels behind tiles.
Surface finish
Tiles, mosaic, plaster or liner: what you see and touch.
Skimmer
Draws surface water to the filter. Joints between skimmer and shell are a common leak point.
Return inlets
Filtered water flows back into the pool here.
Main drain
The outlet at the deepest point, connected to the pump by buried pipework.
Pipework
Suction and return lines, often under decking. Leaks here are invisible from the pool.
Balance tank
Holds the water of overflow and infinity pools. Its level hides or reveals losses.
Pump
Moves the water through filter, chiller and back. Seals and bearings wear out.
Filter
Sand, glass or cartridge media that hold back dirt. The pressure gauge tells when to clean.
Chiller or heat pump
Cools the water in summer, sometimes heats it in winter.
Lighting
Underwater lights in sealed niches, fed by a low-voltage transformer.