Many older ranges that we restore were manufactured before the automatic oven lighting systems were in place. Back in the old days you had to turn on the gas and light the oven manually with a match. The great thing about these old ranges is that they never break down. Aside from needing a valve rebuilt every fifty years, they are dependable and work like clockwork. The problem is that people are undependable. They turn on the gas, stop to answer the phone, text a friend, yell at the kids, and then, BOOOM they go to light an oven full of gas. Now they are lying on the floor on the other side of the room wondering what happened. Of course this is an exaggeration. Most people who have these ranges have been safely using them for decades. It is the younger generation, who text and cook, that have to be careful. Therefore most places require the installation of a safety system.
A safety system is a fancy name for automatic ignition, which is a fancy name for “when you turn the stove on, it lights without using a match” and even more important is the safety feature. If there is no flame in the oven, the gas won’t go to the oven burner, thereby making it safe.
Safety systems are not a prefabricated thing that you order from a manufacturer. Usually you have to buy a series of parts and gas lines and cut and bend the lines to get them to fit the stove that you are working on. The system takes hours to design and create. Safety systems are a necessary expense. They come with a one year warranty on all parts.