RCD tripping

[canuhelp]

My RCD trips on a regular basis between 7-8am on a weekday. I've had circuits checked by electrician and can find no problem. I have a built in fridge freezer which is 15 years old and could this be the cause. If so why does it happen during this time. Does not appear to go off at weekends and only very occasionally at other times. What could be the cause ?

Could it be anything to do with large users such as JET or Diamond Light Source causing any change when they come on line.

If I was certain it was the fridge freezer I would change it. How can I check ?

Thnx

 

[LiamPope]

If I was certain it was the fridge freezer I would change it. How can I check ?

Eat/give away/sell/dispose of food

Disconnect fridge/freezer

See if RCD still trips

 

[ericmark]

My freezer has heating elements that are auto triggered I would guess on a timer as part of the frost free system. This could happen at a set time. But I would have thought if unplugged then clock would reset and the de-frost time would change.

In most houses there are many items causing earth leakage and it is a combination that causes the tripping. Computers and other IT equipment are main offenders each having a filter to stop spikes which also leaks a little power to earth.

The use of RBCO's rather than a master RCD can help as the leakage is spread between more devices. The main test tool I use is my PAT tester which measures the leakage but of course you are unlikely to own one.

However most houses do have two RCD's and plugging the freezer into the other supply and seeing if the fault still trips same RCD or if other RCD trips would seem first step.

Spikes on the line can cause tripping and my RCD's do tend to trip with electrical storms. The RCD's are not all the same and some are better than others at not tripping with spikes. There is one make with warning lights to tell you when the leakage is approaching the trip level but I can't find the web site where I read about them.

Also one can have dedicated sockets without RCD protection for fridge and freezer.