Checking the thermostat, given its non-separable design, must be carried out in the following order. Place the thermostat housing on a container of water so that the thermostat itself is immersed in the liquid. Heat the thermostat, fixing the temperature, while it should not touch the walls of the container.
At a temperature of about 88°C, the thermostat valve begins to open. Continue heating the water, at an intensity of about one degree per minute, and watch the valve open. Record the full opening temperature of the valve. Stop heating and record the temperature of the complete closing of the valve. Compare the results obtained with the technical data for the thermostat.