I would suspect the thermal coupler is bad or at the very least out of adjustment. The Thermal Coupler must be in the flame when the pilot is lit. If it is close but barely being touched by the flame it will do just what you are experiencing. If it is in the flame replace it.
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I would suspect the thermal coupler is bad or at the very least out of adjustment. The Thermal Coupler must be in the flame when the pilot is lit. If it is close but barely being touched by the flame it will do just what you are experiencing. If it is in the flame replace it.