How do I trick the temperature sensor in the boiler into not switching on the heater?

Hello everyone.
I have this problem, I need to fool the temperature sensor so that the system "thinks" the water is hot and does not switch on the heater.
The sensor is screwed into a metal tank.
There are two wires (red) connected to the temperature sensor.
I measured the voltage on the cold boiler when the water starts to heat and on one wire there is a voltage of -0.28 V on the other 3.88 V after heating when the power for the heater is disconnected, the voltage on the first wire is -0.28 V on the second wire 2.86 V In addition, I checked if the meter shows a voltage between both wires. With the heater off it is 4 volts Well and I have a conundrum. Who can help, what else should I check to help assist?
I always try to dig through the forum for solutions but this time I have failed and need to get a parade of professionals, in case I miss a spot on the forum I will ask for a move.

What kind of controller is this? Isn't it simpler to disconnect the power supply to the heater? or the timer?
Not much data beyond that

Wouldn't it be simpler to state which bojrer you are referring to - the symbol

I cannot disconnect the power supply because an error is immediately displayed. The machine must see that the water is hot. I thought I would implant a resistor and that would be the problem, but here it is not. What data is needed.

Hello
There is nothing to combine there are only a few types of sensors e.g. pt 100, ntc etc. Cut the wire, turn off the power, check the resistance. E.g. pt100 is supposed to be about 100 ohms plus a measurement of about 1 - 10 ohms. Depending on conditions of course.
You will find resistance data for the sensors in question on the internet. Measuring the voltage will lead to nothing.

mobydex wrote:

several types of sensors e.g. pt 100, ntc etc

Here literature on how many types there are and how they work .
http://ampero.com.pl/katalog/AMPERO_KATALOG.htm