The catamaran's shallow bilges allow little room for bilge pumps. I had initially purchased Rule 1500 pumps that were recommended based on tests by West Marine and Practical Sailor. I quickly found out that the space would not allow them, they were just about an inch too tall for the space. Another trip to West Marine to swap them for Rule 1000 models, which were in a much more compact square shape. The installation presented several challenges; no space available for the switch's on the distribution panel and all the circuits were basically fully loaded on the distribution panel, also the plumbing required finding a place to go from the pumps to the through hull on the sides.
For the plumbing the port side was easy since their is an access hatch for the shower head that provided enough space to run the hose and even drill the hole from the inside. The hose runs forward in the bilge and then up into the shower access space. Using an extra foot of so of hose I formed a large loop above the through hole to add a bit of safety to the prevent water running back in through it. This would be rare since the exit is about 2 feet above the water line.
The plumbing on the Starboard side took a little more thinking. The hose runs as follows, forward in to the master cabin, up behind the built in drawers, back through the side of the storage bin and down out through the side. This naturally puts a loop in the line and make the inspection of the through hull and hose easily in this storage bin that is accessed from the top. The float switches are designed to have no moving parts, only a sensor on the bottom that detects water.
The wiring used is the special bilge pump wire that is designed to be in water. The wiring was run from the second distribution panel, which I added on the port side since no space was left on the primary panel. The switches, which offer on/off/automatic options were also mounted on this board.