Hi All,
Fresh problem with my Puma 80.
I have scoured the forum but can't find a match, so here we go.....
Everything seems to work OK, but when demand is on CH, after a few seconds of burner operation a knocking develops which builds into a steady rhythm until the burner cuts out. Definitely too loud and regular to be normal.
Seems fine when demand is for dhw, when pouring bath etc.
fault seems intermittant in that sometimes the burner cycle is short and therefor no knocking develops, however when the burner cycle is long the knocking occurs, I am not sure but the long burner cycles do seem longer than usual although I have never had the need to judge its cycle time before.
The dhw and ch settings are both on minimum, the boiler output on the pcb is at around 3/4 (3 bed terrace house, 10 rads).
The red light on pcb indicating flow switch operation for dhw comes on and off as expected.
The pump and wax capsule in the diverter are both less than two years old, the system was also flushed and treated around the same time.
Any ideas would be much appriciated as I have the fear that this fault will develop into a real problem and it is mighty cold out there!
thanks all, dave.
Fresh problem with my Puma 80.
I have scoured the forum but can't find a match, so here we go.....
Everything seems to work OK, but when demand is on CH, after a few seconds of burner operation a knocking develops which builds into a steady rhythm until the burner cuts out. Definitely too loud and regular to be normal.
Seems fine when demand is for dhw, when pouring bath etc.
fault seems intermittant in that sometimes the burner cycle is short and therefor no knocking develops, however when the burner cycle is long the knocking occurs, I am not sure but the long burner cycles do seem longer than usual although I have never had the need to judge its cycle time before.
The dhw and ch settings are both on minimum, the boiler output on the pcb is at around 3/4 (3 bed terrace house, 10 rads).
The red light on pcb indicating flow switch operation for dhw comes on and off as expected.
The pump and wax capsule in the diverter are both less than two years old, the system was also flushed and treated around the same time.
Any ideas would be much appriciated as I have the fear that this fault will develop into a real problem and it is mighty cold out there!
thanks all, dave.