<prompt> Human: Before I moved into my apartment this summer, my landlord who lives on a lower floor of the house mentioned to me in an email about typical heat costs that the thermostat needs to be kept at or above 65 F in winter to prevent the pipes from freezing. I didnt make any notice of this at the time and had since forgotten the exchange. The heats been on for a month or two now, and Ive had it programmed for 67 during the day and 61 at night. I was researching Nest thermostatshow to set it when I go out of town when I found the email where she says it has to be 65.Im no expert, but everything I can find online suggests that under normal circumstances 50-60 is a safe range, and my landlord has said things that dont make sense before. Is it a mistake for me to just pretend she never said anything, set it lower and leave the cabinet doors open when i go out of town? I recognize the obvious thing to do here is _talk to her_, but shes extremely difficult to deal with and is on a bit of a power trip since her electrician confirmed my suspicion that I was paying for her units electricity use and she was paying for mine. She owes me money from this error and I dont want to start another argument, but I also dont want to pay to keep an empty apartment unnecessarily warm all winter.Tl;dr: Can anyone tell me what risks Im taking if I just set the thermostat to 55 or even 60 when I go out of town? Are there any legit reasons the apartment might actually need to be heated to 65 all the time to prevent pipes freezing?Details that might be relevant:My apartment is the top floor of a three story rowhouse, split into three apartments. There is one room with a lot of windows that is a little drafty and stays colder than the rest of the apartment, but there is no plumbing in that room.  <response>: It entirely depends on construction, plumbing and outside temperature and the duration of that temp. No one here can answer this question for your particular apartment definitively. Opening cabinets very well may not be enough. They could have plumbing on outside walls that are poorly insulated. 