I have 16 AntMiner S1's in a room (along with other miners), and most of the days, they are around 58c-59c. I've had them running for over 3 months, no problem so far, but I do have outside air coming into that room and air expelling from that room to the outside.
Also, I believe the Ants are set up to cap at 65c by default. Once you reach that temp, they are "supposed to" throttle the hashrate to lower the temps, but I do not know that from experience, as I've never hit more then 62c.
I would strongly recommend some type of air circulation while you are away, even into your house, so it could have heat dissipation.
Maybe someone else can give you better ideas
EDIT: Also, you could underclock them while you are away. Run them at 275Hz instead of the default 350hz. You'll have lower hashrate, but also much lower heat.