I am sure this will have been asked a number of times before, so sorry if it has...
I needed to replace the portsmouth valve on the cold water tank that feeds the hot water tank recently. As the old one was prehistoric, and wouldn't budge, I cut it off, so also had to replace the brass 90 degree elbow as well.
However, I cannot seem to get a watertight seal between the 2 parts (both threaded - 1/2 inch). I made sure there was no vertical stress on the joint so that it would be in line and i've wrapped PTFE tape around the male part of the thread (6 or 7 times round), but there's always a slow drip. I've tried varying the number of times the tape is wound round the thread, removing the old stuff each time, but to no avail. Should it be wound round a lot more, or is there another method of creating a watertight seal?
Many thanks in advance.
I needed to replace the portsmouth valve on the cold water tank that feeds the hot water tank recently. As the old one was prehistoric, and wouldn't budge, I cut it off, so also had to replace the brass 90 degree elbow as well.
However, I cannot seem to get a watertight seal between the 2 parts (both threaded - 1/2 inch). I made sure there was no vertical stress on the joint so that it would be in line and i've wrapped PTFE tape around the male part of the thread (6 or 7 times round), but there's always a slow drip. I've tried varying the number of times the tape is wound round the thread, removing the old stuff each time, but to no avail. Should it be wound round a lot more, or is there another method of creating a watertight seal?
Many thanks in advance.