Jandy Deck Jet Installation Manual

Installation Instructions

Jandy® Sheer Descent

Installation Manual

THIS UNIT MUST BE INSTALLED ACCORDING TO THE MANUFACTURER'S INSTALLATION

INSTRUCTIONS. PLEASE READ AND FOLLOW ALL INSTRUCTIONS. PLEASE SAVE THESE

INSTRUCTIONS.

PREPARATION AND INSTALLATION INSTRUCTIONS

This manual provides easy reference illustrations to help you identify each part of the Sheer Descent Waterfall. Use this
manual to guide you through the routine procedures and adjustments for a trouble free installation. These instructions were
developed with the aid of experienced contractors and has proven to be a simple, yet consistent and trouble free, method of
installation.

During all phases of the installation, care should be taken not to damage the Sheer Descent Waterfall. Keep the unit in the
original packaging until the site is prepared for permanent installation.

The Sheer Descent Waterfall is available in standard sizes from eight
inches to eight feet in length and is shipped complete with safety
tongue installed in the opening of the waterfall. See figure 1. The
protective tongue keeps the spillway opening clean and damage free.
DO NOT REMOVE THE TONGUE until the start up of the pool
equipment. The safety tongue must be left in the opening during the
entire installation, or damage to the unit, which would effect its ability
to perform, may occur.

Tongue
(Do not remove
prior to start-up)

Figure 1

EXCAVATION & STEEL MODIFICATIONS

It is recommended that the area designated for the Sheer Descent Waterfall be marked off with colored stakes, yellow
construction ribbon, or similar material during the framing process, prior to excavation. In preparation for the installation
of the steel rebar, mark the EXACT area designated for the Sheer Descent Waterfall. To allow room for notching the bond
beam and installing the unit, offset the steel pattern by 3 inches below the original form and 1 inch on both ends of the
Sheer Descent Waterfall. For example, if the Sheer Descent Waterfall is 4 feet in length, offset the steel pattern to measure
3 inches down from the top of the frame and 50 inches in length (this allows 1 inch of space on each side of the Sheer
Descent unit). See figure 2.

Steel off set

Figure 2

Note: Notching of the bond beam is the next
step in the process. The change to the
steel will make the notch a simple procedure.

3½" wide x 3½"

deep notch

Finished notch in beam

2½"

Top of raised bond beam

Page 2

Feet of Elevation

Feet of Projection

Gallons per minute per foot

Guideline is for 1ft. to 4ft models

7

1

2

3

12

9101215 20

Manifold

Rock trap

Sheer Descent Waterfall back feed
plumbing for 6, 7, & 8 ft. lengths.

Beam

Center

CONCRETE INSTALLATION AND MODIFICATIONS

As the concrete installation (or similar process) nears completion, a notch must be cut into the inner edge of bond beam in
the same area at which the steel was offset to allow for the installation of the Sheer Descent Waterfall. See figure 3.

CUTTING THE BOND BEAM

FOR SHEER DESCENT WATERFALL SIZES 8" THROUGH 5'

Select the EXACT location for the Sheer Descent Waterfall.
The notch in the bond beam should be cut 3½" deep by
2½" wide and 2" longer than the length of the proposed
Sheer Descent Waterfall (1" per side). For example, if a

Tile

4' model is to be installed, the notch length should be 50"
(48" + 1"+ 1" = 50"). In addition, mark a single slot on
the top of the beam in the center of the proposed notch

Tongue

3½" wide by 3½" deep. The notch will be used to plumb
1½" pipe to the Sheer Descent Waterfall. Mark the bond
beam and proceed with cutting the beam.

FOR SHEER DESCENT SIZES 6', 7', AND 8'

Mark and cut the beam as instructed previously, with the exception that two notches are required on the top of the beam
for piping. Longer waterfalls require more water; consequently, two plumbing lines are required. The top of the beam
should be marked for these units as follows: NOTE: These measurements are from the center of the Sheer Descent

Waterfall unit.

3½" wide x 3½" deep notch

2½"

3½"

Figure 3

Length Plumbing Location
6 foot 1 foot 6 inches to the right and to the left from the center line
7 foot 1 foot 9 inches to the right and to the left from the center line
8 foot 2 feet to the right and to the left from the center line

The notches should be 3½" wide by 3½" deep. See figure 4.

MAKE SURE THE CUTS IN THE BEAM ARE PROPERLY COMPLETED BEFORE PROCEEDING.

PUMP SIZING AND INSTALLATION OPTIONS

One of the advantages of the Sheer Descent Waterfall is the ability to provide a continuous sheet of water with a minimum
of water flow. A standard four foot model, for example, requires only 40 gallons per minute to operate. In order to size
your pump properly, refer to the Water Flow Requirement Chart. In most
cases, a properly sized standard swimming pool pump will operate the Sheer
Descent Waterfall and filter the pool with little loss of total water turnover. As
a general rule of thumb, the Sheer Descent waterfall requires approximately
10 gallons per minute per foot with little head loss. For more a dramatic effect,
more water gallonage can be applied to project the waterfall further away from
the wall. NOTE: When plumbing multiple falls, add the total length of
waterfalls together to determine GPM required. e.g. When plumbing two
(2) 6' units, you now have 12' of waterfall, which requires 120 gallons per
minute.

Figure 4

EXISTING POOL FILTER PUMP INSTALLATION

The installation of the Sheer Descent Waterfall using the main pool filter pump
is the most common plumbing system, due to the unique low flow aspect of the
waterfall system. Simply plumb a three way valve on the return line, after the
filter, and plumb the waterfall feed line in a minimum of 1½" PVC schedule
40 pipe. Units above 5' in length need a minimum of 2" plumbing.

Page 3

SEPARATE PUMP FOR THE SHEER DESCENT WATERFALL

If multiple waterfalls are being installed, or a Sheer
Descent Waterfall 6' or longer is being installed, we

Cantilever edge

recommend installing a separate pump. When
plumbing a pump dedicated for use by the Sheer
Descent, a separate suction line to the pool must be

Sheer Descent unit

Tile

plumbed. This should be plumbed in a minimum of
2" schedule 40 pipe.

Water line

NOTE: At least one anti-vortex safety suction
cover must be installed at pool side as a safety
precaution. The anti-vortex suction cover is
recommended to be positioned 18 inches above

Anti vortex
cover

the floor of the pool.

Next, a Sheer Descent filter/strainer (part #3456),
or equivalent, must be installed on the return side
of the pump, between the pump and the Sheer
Descent Waterfall. A FILTER IS REQUIRED
for separate pump installations, as large debris
must not be allowed to enter the Sheer Descent
unit. For installations requiring up to 60 gallons per minute, use one Sheer Descent filter. For higher water requirements,
use two or more filters plumbed in parallel. A separate return line, with a three way valve plumbed in such a way that
water can be balanced between the Sheer Descent Waterfall and return back to the pool, is also required. See figure 5.

Conventional
concrete decking

Suction line

Figure 5

Rock trap

Separate return
to pool

Jandy three
way valve

Sheer Descent
filter/strainer

Filter
pump

PLUMBING THE SHEER DESCENT WATERFALL

WATERFALL RETURN LINE PLUMBING

The waterfall feed line, from either the main filter pump or a separate pump, should be plumbed in a minimum of 1½"
PVC pipe. NOTE: Two inch plumbing or larger is suggested for waterfalls over 5 feet in total length. Refer to
Hydraulic Guideline Chart for specifications. The feed line should end near the back of the bond beam near the center of
the waterfall location.

It is important to have a valve located in a convenient location on the feed line to regulate the flow of water to the Sheer
Descent Waterfall. A Jandy three-way valve is suggested to be
used as the "T" from the return line of the pool to the Sheer
Descent Waterfall. A properly plumbed valve in that position will
allow full control of the water to the Sheer Descent, as well as to
the rest of the pool. In most cases, this valve can be located after
the filter near the equipment pad. See figure 6.

NOTE: All water to the Sheer Descent must be filtered.
Those systems using a separate pump must use our separate
filter (part #3456) to prevent debris from entering the Sheer
Descent unit.

Figure 6

Return to pool

Jandy three

Filter

way valve

Pump

Suction
from pool

Rock trap

Water to
sheer descent

H YDRAULIC GUIDELINE CHART

•Use minimum of 1½" pipe.

•Use minimum of 2" pipe for runs in excess of 60

feet or if Sheer Descent unit is over 5 feet.

•Dedicated plumbing lines are recommended.

•Maximum recommended flow for a typical installation:
1½" pipe for 60 GPM

2" pipe for 100 GPM

2½" pipe for 140 GPM

3" pipe for 225 GPM

Typical pump performance at 50 Feet of head

½ HP = 26 GPM
¾ HP = 58 GPM

1 HP = 68 GPM

1½ HP = 93 GPM

2 HP = 106 GPM
3 HP = 140 GPM