Can we just connect to the gas line that goes into the furnace?)

My husband and I were talking about putting a fireplace in the living room. It was a subject that had come up several times, but nothing ever happened. When we were visiting his brother one afternoon, we saw ‌he had installed a gas fireplace in their living room. My husband asked how he could put the gas line into the house? He said that was a simple job, but had he had a gas furnace, he could’ve probably just connected to the gas line that went into the furnace. My husband started thinking about this since we had a gas furnace. He called the HVAC company and ask about the probability of connecting to the gas line that went into the furnace when we put in our fireplace. The HVAC technician wasn’t sure if it was a good idea, and he said he had never seen it done that way. He said it may be safer to run a direct gas line from a gas tank into the fireplace instead of connecting directly into the furnace. My husband is all about safety, and so was I. We didn’t want to do anything that was going to cause a fire or an explosion in our home. Instead of installing a gas fireplace, we opted to install an electric fireplace insert into a fake fireplace setting. It looks just as pretty even if it doesn’t throw off a lot of heat, but it was the ambience that we were going for and not the heat. Two weeks later, we were sitting in front of our electric fireplace listening to the fake logs crackle and enjoying the ambience.
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