well i emailed prog growth and asked them some Q's . they said 1 yr warrenty. they said the relays come back at a rate of 1 in 40 . what usually happens is one side of the relay stops flipping , only one side then works . i wonder if you can change out the relays yourself when they go ? are the relays parts inside? . i have no clue . you would think a relay is a popular grow room tool, seems no one uses them .