He was successively an assistant master at Clifton College, a Housemaster at Harrow and finally Principal of King William's College, Isle of Man.
Previously he had been a housemaster at Aiglon College, a Round Square affiliated school in Switzerland and became chairman of the board of governors upon retirement.
Ridler was the daughter of H.C. Bradby, a housemaster at Rugby School in Rugby, Warwickshire, England, where she was born.
In 1995 Fr Bernard Green, then a housemaster, was arrested after indecently assaulting a sleeping boy in one of the school's dormitories.