In this video, Ask This Old House heating and plumbing expert Richard Trethewey explains how to get the most out of each type of blowtorch.
1. Richard says your choice of blowtorch depends on the type of job you are doing.
2. For smaller jobs involving ½-inch copper pipe, it's best to use a pencil-tipped propane-fueled torch.
3. For larger jobs involving copper pipe ¾ inch or more, it's best to use a hotter flame from the MAPP-gas-fueled torch.
4. To make a copper-pipe connection: Clean the outside of the pipe and the inside of the fitting with an emery cloth.
5. Apply flux to the pipes and make the connection.
6. Apply the tip of the flame to the flux connection.
7. Once the flux begins to melt and drip, place solder on the opposite side away from the flame.
8. The flame will draw the solder all the way around.
9. Once the solder is drawn around, remove the flame from the pipe and let the connection cool.