5755000H
Copyright © Liberty Pumps, Inc. 2018 All rights reserved.
– 7 –
Freezing:
Ensure all pipework susceptible to freezing is adequately
insulated or heated. In unheated buildings, the toilet, piping, and
macerating unit must be properly winterized. Use plumbers’
anti-freeze or drain completely. The battery should also be
disconnected.
Discharge Extension:
An optional discharge extension [P/N
K001184 sold separately] allows the macerator to be positioned
behind a wall. For example, the macerator could be positioned on
the floor of a linen closet or utility room. Do not fully frame unit
into a wall as access to macerator must be maintained.
Toilet Placement:
The toilet hold down fasteners should be
located 16 inches from the wall and spaced 7 inches apart. This
assumes a typical baseboard of 3/4” x 5-1/2” with 3/4” quarter
round. Actual baseboard dimensions must be taken into account
during the installation and thus rough-in dimensions may change.
Tub/Shower:
Water height will be 4½ inches in the macerator
tank before the unit starts pumping. A shower stall floor must be
well above this level. Liberty Pumps recommends at least 6–8
inches to ensure proper shower drainage and prevent any
backflow.
Figure 1. Typical Applications
Pipework:
All pipework should be copper, PVC, or CPVC. Do not
use flexible piping. Support hangers should not be less than 4 ft
apart to prevent pipe rattling.
Pipe Supports:
All sanitary pipework must be supported in
accordance with the pipe manufacturer’s recommendations.
Avoid dipping or trapping, which may cause the buildup of
residual solids and subsequent blockage.
Bends:
Wherever possible, long sweeping bends should be used.
Do not use short elbows. If sweeping 90° elbows are not available,
use two 45° elbows to make a 90° turn.
Shut-off Head:
The macerator has a shut-off head of 36 ft. All
frictional losses from horizontal runs and elbows need to be
accounted for. The minimum flow rate for 1” PVC schedule 40
pipe is 5 gal/min compared to 3 gal/min for ¾” PVC pipe.
Gravity Fall:
The unit accepts wastewater by gravity; it does not
vacuum in water. All inlet pipework must have a positive gravity
fall (1/4 inch per foot drop minimum).
Vertical Lift:
If vertical lift is required, this must precede the
horizontal pipe run. All vertical lifts should rise as close to the
macerator as possible, allowing only for the need to clear the
toilet tank. The initial horizontal run should not exceed 12 inches.
Once the horizontal run is started, do not change directions in a
vertical manner.
All discharge piping from the unit should run either directly
vertical or in a horizontal plane (with a minimum 1/4 inch per foot
drop) to the point of discharge. Pipework must not be installed
with a diagonal upward slope from the unit to the point of
discharge. Long downward pitched runs of discharge piping, or
piping where the point of discharge is at a lower elevation than
the macerator unit, should be designed to prevent siphoning from
the macerator tank.
Friction losses from horizontal runs without 1/4 inch per foot pitch
will reduce the amount of vertical lift the system is capable of
handling. Refer to Figure 3. Consult factory for proper sizing if
there are long runs or multiple elbows.
To pump vertically and horizontally, calculate 3 ft of vertical lift as
equivalent to 30 ft of horizontal run. Each bend or change of
direction gives a pressure drop, which must be calculated into the
total head of the unit. As an estimate, reduce discharge height by
3 ft for each 90° bend.
For example:
1” schedule 40
PVC pipe is used for the
discharge and runs
horizontally for 1 ft, then
turns 90°, and rises 5 ft
vertical. Then it travels
horizontal with another 90°
turn (3 turns in total) and
connects with the soil-stack.
Refer to Figure 2.
Calculations:
[
A
] Total vertical lift 5 ft= 5 ft
vertical
[
C+D+E
] Total horizontal run
43 ft = 4.3 ft vertical
[
B
] Total of three 90° elbows
= 9 ft vertical
Add the three calculation
totals together to get 18.3 ft
of vertical head (lift). Referring
to Figure 3, the application
would result in a flow rate of
23 gal/min (60 Hz).
Figure 2. Example Calculations
Figure 3. Performance Curve
Tub / Shower should be installed on
a riser to accomodate the p-trap.
All fixtures must be properly vented per applicable local plumbing code.
1 ft
[30.5cm]
5 ft
[1.5m]
30 ft
[9.1m]
12 ft
[3.7m]
B
B
B
A
D
E
C
