Hope you found a solution. Sleeping in the low 60s is not recommended. That reminds me of the apartment in Boston I had (really it was an attic of an old house). Several times a winter, always on a Friday night, the furnace would break. It is difficult yo get someone to come out on Friday night apparently and I would end up sleeping in a very cold apartment (in the 50s) on the floor by the fireplace and space heater. Not fun.
We spent a lot of Sunday insulating the outside pipes and spigots, and covering all the vents to the crawlspace. We also kept some dripping faucets last night but it barely got into the 20s. Guess it is better to be safe than sorry (although I could have used that time on Sunday to work with my coauthor who is in town).