Luhrs 300 Open
SOP# 05.12.03
Standard operating procedure for a vacuum flush toilet and the
removal of an electric toilet
Step 1.) Removal of the electric toilet
 Remove the mounting bolts from the base of the toilet.
 Remove any hoses that are connected.
 Remove the electric flush button and butt splice the wires together (using 10-12
heat shrink connectors only).
 Remove all the ¾” brass used for the electric head water supply and patch the
hole.
 Remove the 1 ½” mpt x 1” HB pvc fitting from the waste tank and replace it with
a 1 ½” mpt x 1 ½” HB (using Teflon paste).
Step 2.) Installing the vacuum generator
 Before setting the vacuum generator the shower sump may need to be shifted to
the port side to allow room.
 Facing the discharge to the waste tank, set the vacuum generator (approximately
3’ft from generator to the tank).
 In the sump area then measure for the proper hose length to connect to the tank.
 Using Teflon paste, connect the 1 ½” sanitary hose to the tank and then slide the
vacuum generator into place and secure it down (using #10 x 2” PH).
Step 3.) Preparing to install the vacuum flush toilet
 Install a large pie eye in the face of the cabinet to access the button wires and to
ease routing of the 1 ½” sanitary hose.
 The electric toilet wires will need to be extended 8’ft and covered with flex.
 Route the wires through the sub floor and through the inboard, port stringer to
the sump area where the vacuum generator is going to be mounted.
 Drill out the head base with a 4” hole saw. Then drill out the sub floor the same
size.
 Using a 2 ½” hole saw oblong the sub floor angled towards the forward inboard
chase hole going to the bilge.
 Drill a hole for the Wema waste monitor where the electric flush button used to be
(if it gets this option).
 If it gets a monitor the wires are capped and tie wrapped to the harness.
Step 4.) Installing the vacuum head toilet
 Place the vacuum flush toilet onto the mounting base.
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Mark for the lag bolts that secure it down and for the 1 ½” sanitary hose to be
routed thru the cabinet face.
Move the toilet out of the way and drill the mounting holes 13/64” and drill the
chase hole for the hose 2 ½”.
Install the chase ring.
Route the 1 ½” sanitary hose thru the chase ring and turn back 180* to be routed
through the oblong hole in the sub floor to the inlet of the vacuum generator.
Route the fresh water feed line from the head through the face turn the hose 180*
towards the center bilge.
Tee into the connection from pump to make hose connection to the head.
Mount the head using the lag bolts that come with it and the caps for a finished
look.