Submittal Sheet

Pump and system sizing instructions
Unilift CC, KP, AP
7
57
7. Pump and system sizing instructions
Pump and system sizing
instructions
The information needed and steps required to properly
size a wastewater pump and pumping system are
listed below:
1. System capacity (GPM required)
2. Total dynamic head
3. Size of solids
4. Pump selection
5. Basin size
6. Simplex or duplex system
The following pages explain how this information is
obtained and used to properly size the pump and
pumping system.
1. System capacity
System capacity is calculated in US gallons per minute
(GPM).
The best method to determine this figure is through the
"Fixture unit" method. Proceed in this way:
A. Count the water fixtures (faucets, showers, water
closets and other draw-off points) in the building and
their unit values as shown in the chart on page 5.
B. Refer to the graph below to determine GPM.
Note: It must also be determined if there is a liquid
velocity of at least 2 ft per second through the pipe to
carry the solids without clogging. This is ensured if the
flow rate is at least:
Fixture unit values
9 GPM through a 1.25" pipe
13 GPM through a 1.5" pipe
21 GPM through a 2" pipe
30 GPM through a 2.5" pipe
46 GPM through a 3" pipe
MINIMUM FLOW RATE REQUIRED
TM04 2425 2508
20 30 40 50 60 80 100 200 300 400 600 800
TOTAL FIXTURE UNITS
20
30
40
50
60
80
100100
200
S
Y
S
T
E
M
S
P
R
E
D
O
M
I
N
A
N
T
L
Y
W
I
T
H
F
L
U
S
H
V
A
L
V
E
S
S
Y
S
T
E
M
S
P
R
E
D
O
M
I
N
A
N
T
L
Y
W
I
T
H
F
L
U
S
H
T
A
N
K
S
SYSTEM CAPACITY GPM
1000
System capacity based on total
value of fixture units
Fixture unit Qty. Total
Bathroom group:
Wash basin, bathtub or shower and
(direct flush) water closet
8
Bathroom group:
Wash basin, bathtub or shower and
(flush tank) water closet
6
Bathtub with 1.5" trap 2
Bathtub with 2" trap 3
Bidet with 1.5" trap 3
Dental unit or cuspidor 1
Drinking fountain 1/2
Dishwasher (non-commercial) 2
Kitchen sink, domestic 2
Kitchen sink, domestic with garbage
disposal
3
Wash basin with 1.5" plug 1
Wash basin (barber or beauty shop) 2
Laundry tray, two-compartment 2
Shower stall 2
Shower (group) per head 3
Sink (direct flush valve) 8
Sink (service type with floor drain) 3
Sink (scullery) 4
Sink, surgery 3
Urinal (with flush valve) 8
Urinal (with flush tank) 4
Water closet (with flush valve) 8
Water closet (with flush tank) 4
Swimming pool (per 1000 gal capacity) 1
Water softener (domestic) 1
Washing machine 2
Unlisted fixture with 1.25" trap size 3
Unlisted fixture with 1.5" trap size 4
Unlisted fixture with 2" trap size 5
Unlisted fixture with 2.5" trap size 6
Unlisted fixture with 3" trap size 4
Unlisted fixture with 4" trap size 2
Total fixture units =