Step 6 · Solder the New Valve

This is the step most people slow down on. Take it one move at a time — there’s no rush, and you can rewind the clip as many times as you need.

Disassemble the new valve, removing the plastic cartridge to prevent heat damage during soldering. Apply a thin, even layer of flux to all cleaned pipe ends and fittings. Assemble the pipes and fittings onto the new valve body, ensuring the 'UP' or 'SHOWER' port faces up. Position your heat shield to protect the wood framing. Heat the joint with the propane torch, moving the flame constantly. Once hot enough, touch the lead-free solder to the joint opposite the flame; the solder should be drawn into the joint by capillary action. Repeat for all four connections: hot in, cold in, shower out, and tub spout out. Allow the joints to cool completely without being disturbed.