Pre ignition explosion.
This doesn't happen all the time but on occasion it is quite severe and it seems to happen more often when the demand for heat is in quick succession (ie turn the hot tap off and then on again) or when the shower is being used when the demand is on /off.
The burner was corroded and has been replaced and he electrodes have also been replaced and the gap has been adjusted wider and closer but none of this seems to make any difference. The flame picture is good and the gas pressure is good any ideas.
This doesn't happen all the time but on occasion it is quite severe and it seems to happen more often when the demand for heat is in quick succession (ie turn the hot tap off and then on again) or when the shower is being used when the demand is on /off.
The burner was corroded and has been replaced and he electrodes have also been replaced and the gap has been adjusted wider and closer but none of this seems to make any difference. The flame picture is good and the gas pressure is good any ideas.
