In many apartments, especially in the older buildings where a lot of elderly folks live, there might be erratic supply of heat. Even if there is heat, some rooms might not get heated as well. Depending on the outside weather conditions, such as wind direction change, some rooms can get very cold. These kind of conditions can lead to an elderly person catching a cold.
One remedy is to add a space heater in the room. However, there is an issue of when to turn it on. Many elderly folks are concerned about wasting money by leaving the heater on when it is not needed. Unfortunately, temperature could fall in the middle of the night when they are asleep. While all space heaters have a build-in thermostat, a lot of the space heaters does not provide the control to set the unit to a particular temperature. Most are reluctant to leave the heater on without knowing exactly what it is going to do.
With the availability of low cost controller boards like the Raspberry Pi Zero W, it can be paired with temperature sensors and an AC controller module to create a personal Temperature Controller. The controller can be set to turn the space heater on and off to achieve a desired temperature. Also, the sensor can be place right next to the bed, for example, where it should be to provide the proper temperature sensing. The controller can be programmed to turn on the heater only at particular time periods. The controller can also be programmed to log the temperature variations in the room to tweak the placement of the heater, etc.
An example of how to build such a Personal Temperature Controller is posted in the following “Raspberry Pi Zero W Based Personal Temperature Controller” post on instructables. Total cost of the parts is less than $80. Cost does not include the space heater. Any existing space heater can be used with the controller.