Hi. I had an RCD installed in my garden last year to isolate my garden from the house but recently after cleaning my pond and reconnecting the pond pump its causing the RCD to be by passed and tripping the main fuse box in my house. I have tested the RCD by pressing the test button on the RCD and it appears to be working. I changed the fuse in pond pump to a 13amp. Worked briefly then tripped house again. Any suggestions