I have a 499k rayburn with a balanced flue. When we turn the cooker side on it works for a while OK, it could be OK for a few weeks then it will blow out and the kitchen smells of kerosene. If we try and restart it it won't come back on for a while. But then we just press the restart button and it fires up OK. Replaced the solenoids, fitted new oil burner, pecs, photocell has been replaced, but new one is very sooty. We have cleaned the baffle plates. Any suggestion would helpful. Thanks