The RCD plays an important role in your home, and with them now being legally required on modern consumer units, it can become a cause for concern when it keeps tripping. So why does the RCD keep tripping?
Among the most common reasons your RCD keeps tripping is:
- Faulty appliances
- Moisture in sockets
- Incorrect RCD installed
- Overloaded circuits
We’ll investigate them all in a little more detail, but let’s first dig into what an RCD is and why it plays such an important role.
What is an RCD?
An RCD, or Residual Current Device, is a safety system applied to the electricity supply at home or in the workplace.
It’s usually located in the fuse box but can be found between a circuit breaker and a socket. Since the introduction of the BS 7671 standard, all modern consumer units must have an RCD fitted. The reason? The RCD monitors electricity flow and acts as a trip switch, shutting off power in milliseconds if it detects any leakage of current to earth. As a result, the risk of electrical fires and electrocution is greatly reduced.
If your home hasn’t been rewired in more than thirty years and contains its original fuse board, it is highly recommended that you book an emergency electrician in London as soon as possible.
What is the difference between an RCD and an MCB?
An MCB, or miniature circuit breaker, trips when a circuit is overloaded or short-circuited. The RCD will trip when the current leaks to earth, even in small amounts. This is why you might find your RCD tripping but the MCB unaffected. The fault isn’t an overload, but a leakage, perhaps from a faulty appliance, damaged wiring or moisture.
The two devices protect against two different risks, which is why modern consumer units need both.
What causes an RCD to trip?
There are many reasons an RCD might trip. However, some are more common than others.
Faulty appliances
A faulty appliance is one of the most common causes of a repeatedly tripping RCD. This can stem from incorrect installation, a lack of regular maintenance, or a developing fault within the appliance itself. Washing machines, freezers, ovens and tumble dryers are among the most frequent culprits. In fact, anything with a heating element or motor can prove problematic. If your RCD keeps tripping, isolating it to a specific appliance is a good first step.
Damaged or old wiring
If your wiring is frayed, scorched, or showing any other signs of damage, it’s increasingly likely that your RCD will trip. This is because there is leakage, causing the flow of electricity to change. This is most common in older London homes from the 60s, 70s and 80s, which may retain their original wiring. This may require a new EICR to be commissioned or, potentially, your house to be rewired.
Incorrect RCD
In some installations, an incorrect RCD may be fitted. Domestic RCDs are typically rated to trip at 30mA of earth leakage current, which is the threshold considered safe for personal protection. If an RCD with a lower sensitivity rating is installed, it may trip repeatedly under normal conditions. Equally, one with too high a rating may not provide adequate protection. In either case, you’d need a qualified electrician to assess and replace it with a suitable device.
Moisture or water in sockets and electrics
If moisture finds its way into a place it shouldn’t be, such as plug sockets, wiring, bathroom electrics and lighting with insufficient sealing, the RCD will likely trip.
RCD sensitivity
Some RCDs, especially those that are cheap or low-quality, may wear out quickly and trip without reason. Others may be a little too sensitive and trip when any other RCD wouldn’t. If this is persistent, it may be best to replace the existing RCD with a new one.
Overloaded circuits
If too many items are plugged into one circuit, it may become overloaded. Whilst this would typically cause the MCB to trip rather than the RCD, it is still worth being mindful of how many appliances you have running simultaneously, as overloading can contribute to wiring stress and potentially trigger other faults that the RCD will respond to.
RCD switch tripped: What to do
If your RCD is tripping frequently and catches you unaware, don’t worry, five simple steps are likely all you need to follow.
- Don’t panic – The RCD has done exactly what it was meant to do
- Go to your fuse box/consumer unit
- Flip the tripped switch back up
- If it trips again, immediately unplug the items one by one
- If it fails to reset, contact your electrician
How to fix a tripping RCD
As we have seen, there can be a range of reasons for your RCD to trip, and some issues may be hard to detect. This means it can often be safer and more effective to hire an electrician in London from London Property Services to investigate the cause and professionally diagnose it. They can then safely address the issue and fix it. Some causes of RCD tripping are identifiable and easily fixable. One of the easiest ways to identify what is causing your RCD to trip and then take the appropriate action is to follow the steps below:
- Unplug everything on the affected circuit
- Reset the switch on the RCD
- Plug each appliance in one at a time & check for tripping
- Once the RCD trips, you’ll know what appliance is causing it
- If the RCD doesn’t trip, the problem might require further investigation from an electrician
Why is my RCD tripping with nothing plugged in?
If your RCD is tripping with nothing plugged in, the fault is normally within the fixed wiring or the RCD itself. Some of the most common causes for this are damaged insulation in the walls, moisture in the fuse box, pests, wiring faults from recent building work or a faulty RCD. If you notice this happening, you should contact a qualified electrician as soon as possible.
Can I replace a frequently tripping RCD in my fuse box?
You can replace the RCD in your fuse box with a new one, but it isn’t recommended. Whilst the process may be straightforward, it should really be left to trained and experienced experts. Working with electricity is dangerous, and skilled London electricians, such as ours at London Property Services, with years of experience in domestic and commercial electrical work, can replace a frequently tripping RCD safely and compliantly.
Can I remove my tripping RCD?
Removing a tripping RCD is much easier than replacing one. This is because the replacement RCD must undergo specific testing to ensure it is suitable for use before it is applied. However, removing or tampering with an RCD without professional guidance is not recommended. If you believe your RCD needs to be removed or replaced, speak to a domestic electrician at London Property Services who can carry this out safely and in compliance with BS 7671.
What happens if you don’t fix a tripping RCD?
If you continue to ignore a tripping RCD, you could be allowing a hazard to develop into something more serious. A frequently tripping RCD could be a sign of a wider electrical fault or an indication that your RCD is faulty or of low quality. Regardless, it needs to be addressed to avoid putting yourself, your household or your tenants at risk.
Increased fire risk
RCDs play a key role in protecting against electrical fires. If your RCD isn’t suitable or has become faulty, your home could be more vulnerable to fire risk. Read our guide to learn more about how you can prevent electrical fires.
Further electrical faults
If the RCD cannot trip, it may have become faulty and not function properly. This could lead to electrical issues that cause appliances to fail, wiring to deteriorate quickly, an increased risk of electrocution and potentially fire. Without sufficient protection from an RCD, you could be putting yourself and others at risk.
Can London Property Services help me with a tripping RCD?
Yes. London Property Services can dispatch skilled, experienced and qualified electricians to any domestic or commercial property in London. Whether in Hackney, Wandsworth, Barnet or anywhere else in the city, our team is available to help. With same-day attendance possible and a team of fault finding electricians in London on hand, we can use our expertise to detect and remedy the issues with your RCD. Contact London Property Services today to speak to our team and book your electrician.
