ABS vs PVC pipework
For swimming pool pipework and chemical water treatment systems, PVC (polyvinyl chloride) is generally the better choice over ABS (acrylonitrile butadiene styrene). Key reasons and practical considerations:
Performance and compatibility
Chemical resistance: PVC has excellent resistance to common pool chemicals (chlorine, pH adjustments, algaecides) and many treatment additives. ABS is resistant to some chemicals but is more susceptible to degradation from prolonged contact with certain solvents and aggressive oxidisers used in some treatment regimes.
Temperature resistance: PVC (especially uPVC and CPVC variants where used) handles the typical temperature range of pool systems well. ABS can become brittle in colder conditions and may soften with sustained high temperatures; neither is ideal for very hot water but PVC is more commonly specified for pool plant rooms.
Mechanical properties: PVC offers good stiffness and dimensional stability for pressurised pool circuits, and is widely available in pressure-rated DN sizes and fittings.
Installation and standards
Availability: PVC pressure pipe and fittings are widely available in swimming pool industry sizes and pressure ratings; many pool components (valves, unions, skimmers) are designed for PVC connections.
Joining methods: Solvent-weld (glue) PVC joints are standard and form reliable, watertight connections when done correctly. ABS can also be solvent-welded but uses different solvent cements which are less commonly stocked for pool installers.
Codes and norms: Pool builders, plant designers and many local regulations commonly specify PVC for pool circulation and chemical dosing lines. Using industry-standard materials simplifies approvals and maintenance.
Durability and maintenance
Longevity: PVC is proven in pool installations for decades with low maintenance. It resists scaling and is easy to inspect for leaks or damage.
Repairability: PVC fittings and repair parts are widely available, making in-service repairs straightforward. ABS parts are less common in the pool sector.
Specific use-cases and exceptions
Underground drainage: ABS is often used for non-pressurised drainage systems in some countries; for pool balance tanks and overflow drains, purpose-rated drainpipes (often PVC or polyethylene depending on local practice) are used.
Hot water systems: For very high-temperature applications (e.g., spa heaters or plant-room hot-water loops) CPVC or other heat-rated materials may be preferable to standard PVC. ABS is not recommended for hot pressurised lines.
Chemical dosing lines: For small-bore dosing lines carrying concentrated acids or alkalis, specialist materials (PTFE, PVDF, HDPE) or chemically compatible PVC/CPVC may be required rather than standard PVC/ABS.
Summary recommendation
Use pressure-rated PVC (uPVC or CPVC where higher temperature resistance is needed) for swimming pool circulation, filtration, and most chemical treatment piping.
Reserve ABS for non-pressurised drainage where specified by local practice, but generally avoid ABS in pool circulation and chemical dosing systems.
For concentrated chemicals, hot lines, or unusual chemistries, consult material-compatibility charts and a pool plant engineer to select specialist materials (PVDF, PTFE, HDPE or CPVC) as required.