RCD switch trips every day, even when nothing plugged in

Clairlyagenius

So, I just moved into a new house, finally got electricity (yay!)
But over the last three days, the RCD switch on the board trips randomly.. It seems to happen every day, I'm not sure when exactly because it causes all the sockets to stop working, but lights still work.
Does anyone know what could be causing this? It happened even when we had absolutely nothing plugged in.
Originally I thought it was the immersion, coz we don't have water yet and that was on a timer, but I've since turned that off, and it still happened?

meercat

Clairlyagenius wrote: »

So, I just moved into a new house, finally got electricity (yay!)
But over the last three days, the RCD switch on the board trips randomly.. It seems to happen every day, I'm not sure when exactly because it causes all the sockets to stop working, but lights still work.
Does anyone know what could be causing this? It happened even when we had absolutely nothing plugged in.
Originally I thought it was the immersion, coz we don't have water yet and that was on a timer, but I've since turned that off, and it still happened?

Generally a neutral to earth fault. Most likely an appliance with an element. If you definitely have nothing plugged in and everything switched off then it could be on the electrical circuit itself.
Is this a brand new house or a new to you house. If new get the rec back. If a reconnection then get the rec who tested it for you back. Check for moisture ingress on outdoor sockets

punisher5112

Check dishwasher, washing machine and anywhere water and sockets are close by....

This was happening lots in one house and it was dishwasher hose cracked and wetting the socket.

A2LUE42

Clairlyagenius wrote: »

So, I just moved into a new house, finally got electricity (yay!)
But over the last three days, the RCD switch on the board trips randomly.. It seems to happen every day, I'm not sure when exactly because it causes all the sockets to stop working, but lights still work.
Does anyone know what could be causing this? It happened even when we had absolutely nothing plugged in.
Originally I thought it was the immersion, coz we don't have water yet and that was on a timer, but I've since turned that off, and it still happened?

Had a similar issue and it was driving us crazy trying to find out what plug was causing the issue. Turned out to be a faulty RCD.

alan4cult

Is there an outdoor spur socket in the house. Turn off the MCB for this and check if RCD trips.
Otherwise you'll need to turn off half the MCBs and check which half the RCD stays on with.

Clairlyagenius

meercat wrote: »

Generally a neutral to earth fault. Most likely an appliance with an element. If you definitely have nothing plugged in and everything switched off then it could be on the electrical circuit itself.
Is this a brand new house or a new to you house. If new get the rec back. If a reconnection then get the rec who tested it for you back. Check for moisture ingress on outdoor sockets

We just tried it overnight with the fridge plugged out (realised that was the only thing that had been plugged in, it came with the house so we didn't think of it immediately!) Tripped again in the night!
It's new to us, vacant for 10 years, but don't really want to grt the guy who certified it back in, because he took ages last time, and kept standing us up. 😥

Clairlyagenius

punisher5112 wrote: »

Check dishwasher, washing machine and anywhere water and sockets are close by....

This was happening lots in one house and it was dishwasher hose cracked and wetting the socket.

We don't have water yet, so none of those should be wet at the moment!
I was hoping that it's something to do with the fact that we don't have water, and something timed is setting it off, like the immersion trying to heat up. Do you think that's possible?

Clairlyagenius

alan4cult wrote: »

Is there an outdoor spur socket in the house. Turn off the MCB for this and check if RCD trips.
Otherwise you'll need to turn off half the MCBs and check which half the RCD stays on with.

We couldn't find one, but there is a private well, maybe there's a hidden switch for that somewhere outside?
The rcb switch is also the inky one in the line that trips, there's isn't one that trips with it, should there be another one tripping to indicate where the problem is that I could check ?

listermint

Clairlyagenius wrote: »

We couldn't find one, but there is a private well, maybe there's a hidden switch for that somewhere outside?
The rcb switch is also the inky one in the line that trips, there's isn't one that trips with it, should there be another one tripping to indicate where the problem is that I could check ?

One of the MCBs should be wired to the well pump and maybe some other water related stuff like UV lamp if your system has one. That is the MCB you will need to turn off at the board.

The Cush

Septic tank pump/pumps? What type of waste system is in place?

My brother has a similar intermittent fault leading up to first lockdown last year, changed RCD etc., finally narrowed it down to the septic tank discharge pump.

meercat

Clairlyagenius wrote: »

but don't really want to grt the guy who certified it back in, because he took ages last time, and kept standing us up. 😥

Has the rec comeback to do the post connection testing once power has been reconnected.

If you’ve recently had the house tested and certified to get electricity reconnected then any issues should have been discovered/highlighted if testing was completed correctly.

Readings for every circuit should have been recorded and a test record issued to you along with a copy of the certificate

Post the figures for insulation resistance and trip times for the rcd

Ask the rec back as he has already tested the entire installation and should be able to discover the issue relatively quickly

Clairlyagenius

The Cush wrote: »

Septic tank pump/pumps? What type of waste system is in place?

My brother has a similar intermittent fault leading up to first lockdown last year, changed RCD etc., finally narrowed it down to the septic tank discharge pump.

It could be this! We turned off the breaker for the immersion, and two others that were unlabelled.
We do have an Enviropak, and one of them is for that. We're going to wait today and tonight and see if we get a trip, and if not, we'll turn each one back on for a day and see which one trips the RCD. So HOPEFULLY, that's the problem, and at least we can have it narrowed down to fix

Clairlyagenius

meercat wrote: »

Has the rec comeback to do the post connection testing once power has been reconnected.

If you’ve recently had the house tested and certified to get electricity reconnected then any issues should have been discovered/highlighted if testing was completed correctly.

Readings for every circuit should have been recorded and a test record issued to you along with a copy of the certificate

Post the figures for insulation resistance and trip times for the rcd

Ask the rec back as he has already tested the entire installation and should be able to discover the issue relatively quickly

He has, but he never gave us a list of readings or anything.. To be honest it looked like he mostly just tested sockets and lights, I'm not sure if he actually tested the well and Enviropak sewage treatment plant..
I'm kinda hesitant to get him back, because I don't know if I trust that he was thorough! I'm hoping to at least isolate what the problem is, so that we can call a different electrician, and be able to tell them what's broken!

punisher5112

Ask him back, get these on a separate rcbo and then it won't leave the rest of the house out of action.

meercat

Clairlyagenius wrote: »

He has, but he never gave us a list of readings or anything.. To be honest it looked like he mostly just tested sockets and lights, I'm not sure if he actually tested the well and Enviropak sewage treatment plant..
I'm kinda hesitant to get him back, because I don't know if I trust that he was thorough! I'm hoping to at least isolate what the problem is, so that we can call a different electrician, and be able to tell them what's broken!

You’re entitled to the test records sheet(and a certificate)
This test records sheet will be helpful to another rec in determining the issue

If it’s a neutral/earth fault on the circuits then you’ll struggle to identify that yourself

Clairlyagenius

Update! We isolated the problem! It only trips when the immersion is on, so everything else is fine (Thankfully!)
We don't have central heating yet anyway, so I can bring that up and get it sorted when we're getting that installed. For the moment, it just stays switched off at the board 😅

Cerco

Looks like meercat had it diagnosed in post#2.