- Oct 3, 2007
- 1,539
I'm installing my new garage heater and have a slight issue with the connection. The gas regulator on the heater calls for a 3/8" NPT nipple as per the manual, but I tried threading a 3/8" black pipe nipple in that was just laying around and it didn't seem to want to go. I didn't want to force it because the regulator is aluminum and I didn't want to risk wrecking the threads. It's definitely not a flare connection either. What am I missing here?