My thermostat is not clicking on/off automatically, I have called my landlord and they replaced a very old one with a brand new one and it is still not clicking on off automatically, but will manually. I have called them up again to tell them it still only works if I manually change it and they have been and replaced it again but it's still not working!! So I am going to try and sort it out myself. Can anyone give me any idea as to what is wrong and how I can fix it?
If they have replaced it twice, it is likely that the fault lies elsewhere or the thermostat is miswired.
I replaced mine with one that incorporates an indicator lamp to show if it is on (signalling heating system to provide heat)
This type of thermostat incorporates a "heat anticipator" that receives power when the thermostat is "on". If miswired, the heat anticipator can be on all the time and cause the thermostat to think the temperature is always high - and so never switch on the heating.
This particular thermostat operates at high voltage, so unless you are comfortable working with voltages that can easily kill you, you should get an electrician to do any investigation or other work.
There are a huge variety of thermostat designs, so what applies in my part of the world may not apply in yours.