During the winters I get pipe knocking when the CH is turned on.
I usually drain the CH down every 2 years, and add an addictive to help remove the sludge before draining and refilling a few times, followed by 300ml of inhibitor. There is no pipe knocking for 1-2 months then it starts up again. I am wondering what could possibly be causing the sludge. I suspect it is due to not enough inhibitor, but I am not sure. I have a 10 rad system, 6 of which are double panelled.
I used to think that it was solely caused by pipe expansion, but when the rads were on for 2-3 hours, stopped for 2-5 minutes and restarted the pipes would still knock so it can't be an expansion issue.
I usually drain the CH down every 2 years, and add an addictive to help remove the sludge before draining and refilling a few times, followed by 300ml of inhibitor. There is no pipe knocking for 1-2 months then it starts up again. I am wondering what could possibly be causing the sludge. I suspect it is due to not enough inhibitor, but I am not sure. I have a 10 rad system, 6 of which are double panelled.
I used to think that it was solely caused by pipe expansion, but when the rads were on for 2-3 hours, stopped for 2-5 minutes and restarted the pipes would still knock so it can't be an expansion issue.