I'm setting up a shop in my pole barn. I've walled off and insulated a 24' x 40' x 14' high shop area. I've run a nat gas line from my house 3/4 diameter. I tee'd after the meter before it goes into my house. Its approx. 140' long. I got a nearly new hanging heater from my buddy for a good deal-his son works for a heating contractor. Its a Dayton forced air heater 150,00 btu. I haven't hung it yet. I'm wondering if I will have enough gas and if its just way too much btu. My buddy says I will need the size to bring up the temp fast enough. I wont be heating it 24/7, just when I'm working. Any advice?