I have a kelvinator furnace that is blowing cold air - I have cleaned the sensor after reading the answer to some other questions - didn't work I believe the prob is no flame cause according to the diagram a yellow light should be on representing flame and that light is not on. The only light is the red one bliking continuously representing false flame or gas valve relay shortage sooo now I am stuck - Are there any other thing I can try myself so I don't have to pay a service man bill Please help!