It is a very simple controller for central heating pump, equipped with an electronic thermometer. In other words, this construction is an electronic thermostat with adjustable activation temperature and the ability to change the hysteresis, based on this project:LINK.
The thermostat is to control the central heating pump. By default it will be set to enable the pump at 40 degrees Celsius. LED indicates the pump operation. Thermostat disables the pump at about 3 degrees Celsius below the set enable temperature.
Thermometer is based on voltmeter NE 046 circuit. You should give the output voltage of analog temperature sensor LM35DZ to the input of NE 046. This voltage changes linearly with the temperature and is 10mV/*C, so that the voltmeter should be set to 2V so that you can measure temperature in the range of 0-100 degrees Celsius.