Final answer:
Air acetylene, air MAPP, and air propane torches provide moderate temperatures suitable for soldering copper pipes, unlike oxyacetylene torches that deliver very high heat and can damage piping while making them harder to manage.
Step-by-step explanation:
Air acetylene, air MAPP, and air propane torches are preferred over oxyacetylene torches for soldering copper pipes primarily because of the temperature control they offer.
The oxyacetylene torch produces a very hot flame due to the high heat of combustion for acetylene, particularly when burned with oxygen. This intense heat can be overkill for soldering, where a more moderate temperature is needed to correctly melt the solder without damaging the copper piping. On the other hand, air-fuel torches like air acetylene, air MAPP, and air propane produce a sufficiently high temperature to melt solder effectively but at a lower temperature than oxyacetylene torches, reducing the risk of overheating the material. Additionally, air-fuel torches are often more convenient and easier to handle, making them an ideal choice for soldering applications.