Pumps and Heaters
One of the most common causes of electrical shocks in the shower involve instant water heaters or electrical pumps built into the shower. These devices are designed to use a transformer away from the moisture of the bathroom and should have water-proof enclosures, according to the UK D-I-Y FAQ website. When installed improperly, the devices deliver an electrical current through the pipes connected to them.
The pipes in your shower need to have a connection known as a ground to divert any electricity that makes contact with the metal. When this ground is connected to a main water line, it might lead to shower shocks instead of preventing them. Neutral connections used for water mains often create open circuits, according to GridSense. The electricity released by this circuit follows the shortest path available, which is up the grounding line and into the shower in many homes.
Lack of Ground
As water flows through pipes, it creates a slight static electricity charge. This charge usually disperses through the ground that all plumbing is required to connect to. When the plumbing in your shower becomes disconnected from the ground or does not have one installed, static electricity builds up enough to shock you, according to "Ortho's All About Bathroom Remodeling." While static shocks aren't as dangerous as other types of shower electricity, they do indict the chance for fatal shocks because of ungrounded plumbing.
Determining which problem is causing the tingling or pinprick sensations you feel in the shower often requires the help of a licensed electrician. A certified electrician uses testing equipment to find open circuits in main lines, and the water company must repair these problems. Shut off any equipment connected to the shower plumbing to test if a faulty heater or pump is the cause. Checking the connection between the plumbing and the ground is the easiest, if you know where the home's grounding rods are located.