I just was at the Hose Shop to get a new hose for my forge for my new rig. He told me that my old hose was in very poor condition and I need to replace the gas hose every 3-4 years. He was explaining that the hoses deteriorate over time. He also said it is a very good idea to make sure not to keep the line charged all of the time, which I don't do, because the lines are 'vented' and allow a small portion of propane to escape through the insulation. Something like that.

Just a FYI. I didn't know this before. Could be a safety issue.

Hoses need to be replaced at least once every 18 months if not more often. This is due to several issues. 1st, the hoses themselves are subject to pressurizing and depressurizing every time you charge the line. This stress's the lines ability to expand and contract. It also stress's the line's connections and fittings, which are made of metal. which can't expand and contract at the same rate. A bit of history, if I might digress for a bit, for a historical point.

Back in the 70's, GM & Chevy came up with the old VEGA. Great little car but for 1 item. In order to get the mileage they wanted the weight had to be kept down. They did this using a 2 metal type engine; steel block and aluminum heads and manifolds. The expansion and contraction rates of the metals were so different that you had VEGA's blowing engines left and right. Eventually the VEGA was given a standard aluminum engine to solve the problem. But I think the point has been made.

2nd, the hoses are also subject to deterioration from the sun. UV rays have a very nasty habit of causing rubber hoses, even a great many poly-type hoses, to deteriorate over time. Remember the movie 'Andromeda Strain" and the crumbling hoses and seals ? Same issue. The problem you have here is one of safety. You really want the hose to fail under pressure with a hot forge or sparking grinder in the immediate area ? Replacing he hose's and attached fitings is very cheap insurance.

Check your gas grills too!!! Had one of those moments a couple of weeks ago when the hose rotted off at the regulator, was surrounded by a ball of flames. Ahhhh!!!! Do I run like H E L L or turn of the tank?