It's common for many household appliances to generate heat as a normal part of their operation. However, the sockets themselves should not get hot. If this starts to happen, you should immediately unplug all cables and refrain from using that outlet until the issue has been resolved. This might be something you're able to do yourself, but many issues will require the assistance of an electrician.
With that in mind, here are just four common reasons why electrical sockets might grow hot.
1. Overloaded Socket
The number of devices and appliances most households use on a regular basis has grown hugely over the last couple of decades, and that means many homes have far fewer sockets than their owners require. To compensate, it's common to use multiple adaptors to plug more items into each socket. This might be fine as a temporary fix, but powering too many devices from one socket can overload it. When this happens, you'll often notice that socket growing hot.
2. Worn Plugs
In some cases, the fault for a hot socket will lie with the plug rather than the socket itself. When the cables become worn or frayed or the prongs become broken or bent, power won't flow properly through a plug. This may cause both the socket and plug to heat up. In some cases, worn or damaged plugs can even cause a fire, so it's important to stop using that device until it can be properly rewired.
3. Loose or Worn Wiring
When the wiring behind a socket becomes loose or sustains damage, a bad connection will be formed while the electrical current continues to flow. This creates resistance and allows heat to build up. Further signs of loose wiring include bursts of sparks when you plug something in, so this is an issue you should take seriously. If you think a socket's wiring might have become loose or worn, it's important to stop using it until an electrician can assess the situation and carry out any necessary repairs.
4. Overloaded Circuit
You can overload a circuit as well as an individual socket. This occurs when too much strain is placed on an electrical system, usually because too many sockets and switches are connected to the same circuit. This is a common issue in older properties since their wiring won't have been designed around the electrical needs of modern homes, and it's another issue that can cause sockets to grow hot.
For more information, contact a local electrician.