: I'm replacing my hot water heater with a tankless type. The tankless type requires 3/4" npt gas pipe size. My existing gas line is 1/2" teed from a 1" line roughly 20' from my gas meter. The unit is only 190,000 BTU max. Can I survive with the 1/2" gas line? Or, can I keep the tee and increase from the 1/2" to 3/4"?
A quick glance at a sizing chart shows that 20' of 1/2" steel piping can handle only about 60,000 BTU's with an ordinary amount of fittings used. I would have a pro size it accurately, 3/4" piping is probably not large enough either. Another factor would be the existing load on the 1" piping you're planning on connecting to.
Good Luck. e-plumber