Monthly intermittent fault

[DPG]

Well, I am sure, given your standing on here, that you are a decent bloke/landlord. Most, sadly, in my experience are not.

It's OK - no offence taken You're probably right. On both counts Daz

 

[Octopus]

Shame the OP can't post a picture of the CU.

But the way I read is is that the main switch is also the RCD - correct?

 

[Davisonp]

In simple terms, what is earth leakage? and why would it trip the RCD?

"https://www.youtube.com/watch?v=5hL13UjRSoY"

This video shows earth leakage from everyday appliances, and the front room of the house tested has a maximum earth leakage of over 3mA. A full house with washing machines, microwaves Etc can have too much natural earth leakage for an RCD causing it to trip occasionally.
Current regulations require newer appliances to restrict the earth leakage, where older appliances from before RCD’s were required on circuits did not have the same restrictions on earth leakage meaning some older appliances have greater earth leakage. Also, as appliances reach the end of their life, the earth leakage can become worse, so some older fridges can start triping RCD’s as the motor’s start to fail.

A 30mA RCD when working correctly should trip somewhere between 15mA and 30mA.

 

[Octopus]

"https://www.youtube.com/watch?v=5hL13UjRSoY"

This video shows earth leakage from everyday appliances, and the front room of the house tested has a maximum earth leakage of over 3mA. A full house with washing machines, microwaves Etc can have too much natural earth leakage for an RCD causing it to trip occasionally.
Current regulations require newer appliances to restrict the earth leakage, where older appliances from before RCD’s were required on circuits did not have the same restrictions on earth leakage meaning some older appliances have greater earth leakage. Also, as appliances reach the end of their life, the earth leakage can become worse, so some older fridges can start triping RCD’s as the motor’s start to fail.

A 30mA RCD when working correctly should trip somewhere between 15mA and 30mA.

Not sure I agree with this!

 

[sparksburnout]

I watched that vid, and then noticed this one https://m.youtube.com/watch?v=5CBuLHVxqLI. Good old Al, he's so busy saving money he's not noticed that great big yawning gap in the middle of his CU!! Hehe.....

 

[GETWIRED]

Had something a little bit similiar last week, the lady unplugged everytjing and the rcd still tripped. The boiler was fed off the sockets via a fused spur so she didnt unplug it when she unplugged all her appliances. Was a very slow leak on the water pump inside the combi. Maybe something to think about.