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American Air Purger 443 - Are they every 1 1/4" Thread?
I have one of these and I am trying to relay the size to a contractor and trying to save a trip and will be replacing this with a spirovent. The copper pipe going into it is definitely 1.25" but the 443 has threaded ends and the fitting looks like the threads are the same size as the OD of the 1.25" pipe. When I look onlie they all look like 1" but I took a measurement of the threads (male) going into the 443 and they are about 1 5/8" OD. So I think this is a 1 1/4" thread.
What do you think? Thank you