Pinhole leaks are tiny holes, which may not be visible that can occur within water systems, especially in copper pipes. They can cause a lot of water damage and expensive repairs if not addressed quickly. The primary causes of pinhole leaks include:
- Corrosion – This is the most common cause. Internal corrosion occurs with the interaction of water with the pipes surface over time. Water with a low pH or high dissolved oxygen can accelerate the corrosion process.
- Mineral content – Areas with particularly hard water can cause mineral build up or chemical reactions that can weaken the pipe walls.
- Water treatment - Pinholes can also arise where scale had been removed from the internal lining of the pipes, which essentially acted as glue. Once removed, defects are sometimes exposed.
- Chemical treatment – Biocidal dosing such as chlorine dioxide can have an impact on corrosion and cause pinholes if not properly circulated or the levels correctly maintained.
- Water velocity – Excessively fast flowing water, especially in small pipes, can erode the inner pipe surface. This is a common issue in water systems where the water circulation velocity isn’t properly regulated.
- Defective pipes – Pipes with manufacturing defects such as thin walls or impurities in the material can make them more susceptible to leaks.
- Old pipes – Ageing systems are more likely to leak as they wear down over time.
- System modifications - Soldering flux has been regularly attributed to pipework corrosion, with remnants often found in the system after a pipework alteration.
- External factors – Contact with soil, concrete and corrosive substances externally can weaken the pipes from the outside to create pinhole leaks.
Preventative measures can be implemented to avoid the risk of pinhole leaks in your system. Some examples of this are:
Regular inspections of your pipes to monitor scale and corrosion build up.
- Installing water softeners to reduce mineral deposits in the form of scale build up.
- Regular monitoring of any chemical dosing to maintain safe levels and correct pH balance.
- Replacing aging pipes when needed and consider the age of the pipework when contemplating aggressive water treatment such as very high concentration disinfections or de-scaling.
- Review the size and speed settings of any pumps to ensure they are fit for purpose
- Ensure that the system is properly cleaned and thoroughly flushed following any system modifications.
- Make sure that pipework is suitably insulated and protected from the external environment.
While not an everyday occurrence, pinhole leaks do happen and when they do, they can be difficult to trace and costly to rectify. Taking good care of your water service and maintaining a good system condition will help reduce the chances of this becoming an issue in your buildings. If you need any help with your water system management, please get in touch.