Hi there. I have 3/4" cast iron natural gas line entering my house. It's immediately reduced to a 1/2" csst line. This goes about 20' over to a regulator and manifold. On the manifold there are two lines, one going to furnance (110k btu) and a large hot water tank (I'm not sure what the btu is). These seem to be operating fine without issues. What I'm wondering is if I can add a third 1/2" branch to a wall hung space heater (for basement). I'm most interesting in having this as a back up heater in case the power goes out. But I'd also like the ability to use all three at the same time if possible. All three would be located pretty close to the manifold. Will this 1/2" trunk support it or do I need to replace it with 3/4" ?