In front of a crowd of 1131, the visitors took the lead thanks to a second minute Paul Makcey try which was converted by Aled Thomas.
The kicker added to his points tally with penalties in the 17th and 40th minute to see London 13-0 ahead at the interval.
Phil Maynard's team had Joe Carlisle kick a 44th minute penalty only for Thomas to score from another penalty two minutes later.
Jamie Hall ran in a 64th minute try which Carlisle converted but it was Thomas who finshed the scoring with a 70th minute penalty which saw Coventry go down in this Championship game 10-19.
Roman Poutney picture courtesy of Joanne Davies.