My toilet cistern is mains fed but takes several minutes to refill so I decided to change the float valve. This should have been a 10 minute job but I hit problems which were sod's law and Catch 22 rolled into one.
The existing float valve is a Part 2 type so I bought a Part 2 replacement. The existing threaded inlet tail is about 23/8" (60mm) long but only about 11/2" (40mm) long on the replacement, so it would not reach the tap connector. The tap connector is difficult to modify as it is soldered onto a lead pipe emerging from the bathroom wall. It seems a long tail version is only available with Part 1 valves - which seems odd.
I bought a tail extender ie a brass 1/2" MI/1/2" FI. However, when this is pushed onto the tap connector, it barely leaves room to offer up the external backnut to the threaded inlet tail and insufficient exposed thread to wind on PTFE tape for the 1/2" FI connection.
It did occur to me that I could simply swap the valve internals by undoing the large nut inside the cistern but I was worried that another problem might arise to prevent me returning to the original arrangement.
One other complication is that the captive nut on the chromed/stainless steel tap connector does not run very freely/far enough along the short length of pipe up to the shoulder and it is extremely difficult to offer it up to the MI thread when a fibre washer is in place. The original tap connector joint was made with bosswhite and hemp (not a fibre washer) so I suspect it may be hardened bosswhite on the nut thread causing this problem - this would be awkward/impossible to remove. I eventually used several turns of PTFE "string" instead of a fibre washer.
Am I correct in thinking the 1/2" FI could also be connected with an olive to the inlet pipe, as in a normal compression fitting? - this would be easier than using PTFE tape. Though it does seem the olive could possibly misalign unless I paste it in position with bosswhite.
The existing float valve is a Part 2 type so I bought a Part 2 replacement. The existing threaded inlet tail is about 23/8" (60mm) long but only about 11/2" (40mm) long on the replacement, so it would not reach the tap connector. The tap connector is difficult to modify as it is soldered onto a lead pipe emerging from the bathroom wall. It seems a long tail version is only available with Part 1 valves - which seems odd.
I bought a tail extender ie a brass 1/2" MI/1/2" FI. However, when this is pushed onto the tap connector, it barely leaves room to offer up the external backnut to the threaded inlet tail and insufficient exposed thread to wind on PTFE tape for the 1/2" FI connection.
It did occur to me that I could simply swap the valve internals by undoing the large nut inside the cistern but I was worried that another problem might arise to prevent me returning to the original arrangement.
One other complication is that the captive nut on the chromed/stainless steel tap connector does not run very freely/far enough along the short length of pipe up to the shoulder and it is extremely difficult to offer it up to the MI thread when a fibre washer is in place. The original tap connector joint was made with bosswhite and hemp (not a fibre washer) so I suspect it may be hardened bosswhite on the nut thread causing this problem - this would be awkward/impossible to remove. I eventually used several turns of PTFE "string" instead of a fibre washer.
Am I correct in thinking the 1/2" FI could also be connected with an olive to the inlet pipe, as in a normal compression fitting? - this would be easier than using PTFE tape. Though it does seem the olive could possibly misalign unless I paste it in position with bosswhite.
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