I have a thermos of junkers that gives me problems when it is turned on. Gives the spark but not fully turn on, therefore you do not heat the water. I have seen that many terms, junkers are going with batteries but mine is not. We believe that it is the electrovalvulva because it gives the spark but it turns off and retries to turn on. Therefore, we believe that gas if it arrives but does not spark and we do not believe that is the problem of the screen. By what we have seen on the internet, the electrovalvulva can be seen to the naked eye if it is damaged because it has a gomita which is intact and in our case the rubber is good. Could anyway be a problem of the electrovalvulva?