Tenant complaining that it's too cold in the apartment

[Mark Jurgiel]

Hey all,

I have a 2 family home that I rent out in Queens NYC. The tenant on the 3rd floor always complains in the winter time that's it's cold, especially in the bedroom. Everytime I go into the apartment to check it out, it is always warm throughout the house with an average temperature of 75F. I have a hot water boiler and made sure to bleed out all the radiators. When I check the bedrooms it never feels cold. The tenant told me that around 1am it is around 40 degrees F in the bedroom which I find odd because I actually keep the thermostat at 79F between 10pm-7am. I have and ecobee thermostat that is located on the 1st floor with temperature sensors in every room of every apartment that communicate with the thermostat. The coldest I have seen the bedroom that the tenant is complaining about has been 71F. The tenant has even gone and bought a digital thermometer to put in the bedroom and has sent me a picture showing the temp at 59.5F. The thermometer also shows a high temp of 88.5 and a low temp of 47.3 which is odd to me because I can't see a temp difference that big. Also, the bed is located on the wall near the window. Anyone have any suggestions on what I should do?