How to Build a Sprinkler Dry System Conversion
- 1). Install galvanized pipe to attach the air pressure unit. Measure the length of pipe, cutting off the excess with a pipe cutter. Clean off the metal burrs at the end by sanding with 120-grit sandpaper.
- 2). Attach the new piping by soldering the pipe and air pressure system to the main line, also known as the center tree feed, before the line branches to the individual sprinklers. Install the dry valve and trim that will open after the air pressure lessens when detecting heat from a fire.
- 3). Inspect the branching pipelines to determine low points. Cut the pipe at the low point. Sand the pipe ends clean. Affix a tee pipe that will allow drainage back to main drain valve. If you cannot do this with the pipe, you will have to install an auxiliary drain at the low point.
- 4). Remove the exiting pendant sprinkler heads. Take off the elbow end fittings from the pipe. Install screwed tees and the dry pendants.
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