HAYWARD S310T User Manual

Your Hayward Pro Series high-rate sand filter is a high
performance, totally corrosion-proof filter that blends superior
flow characteristics and features with ease of operation. It
represents the very latest in high-rate sand filter technology .
It is virtually foolproof in design and operation and when
installed, operated and maintained according to instructions,
your filter will produce clear, sparkling water with only the
least attention and care.

HOW IT WORKS

Your filter uses special filter sand to remove dirt particles
from pool water. Filter sand is loaded into the filter tank and
functions as the permanent dirt removing media. The pool
water, which contains suspended dirt particles, is pumped
through your piping system and is automatically directed by
the patented filter control valve to the top of the filter tank.
As the pool water is pumped through the filter sand, dirt
particles are trapped by the sand bed, and filtered out. The
cleaned pool water is returned from the bottom of the filter
tank, through the control valve and back to the pool through
the piping system. This entire sequence is continuous and
automatic and provides for total recirculation of pool water
through your filter and piping system.

After a period of time, the accumulated dirt in the filter
causes a resistance to flow, and the flow diminishes. This
means it is time to clean (backwash) your filter. With the
control valve in the backwash position, the water flow is
automatically reversed through the filter so that it is directed
to the bottom of the tank, up through the sand, flushing the
previously trapped dirt and debris out the waste line. Once
the filter is backwashed (cleaned) of dirt, the control valve is
manually resequenced to Rinse, and then Filter, to resume
normal filtering.

INSTALLATION

Only simple tools (screwdriver and wrenches), plus pipe
sealant for plastic adapters, are required to install and/or
service the filter.

The filter system should be installed, not more than 6
feet above pool water level, on a

level

concrete slab,
very firm ground, or equivalent, as recommended by
your pool dealer. Position the filter so that the piping
connections, control valve and winter drain are
convenient and accessible for operation, service and
winterizing.

Assemble pump and pump mounting base, No.
S160TPAK1 or S160TPAK3 (if supplied) to the filter
according to instructions packed with the base.

IS310T-99

1.

2.

(117 cm)

(122 cm)

(62 cm)

MODEL S310T

SPECIFICATIONS

MODEL

NUMBER

S310T

EFFECTIVE

FILTRATION AREA

FT

2 M2

4.9 0.46

DESIGN

FLOW RATE*

GPM LPM

98 371

PRESSURE LOSS AT
DESIGN FLOW RATE*

PSI BAR

4.7 0.33

MAXIMUM WORKING

PRESSURE

PSI BAR

50 3.45

REQUIRED CLEARANCE

SIDE ABOVE

INCH MM INCH MM

18 457 18 457

MEDIA REQUIRED

TYPE AMOUNT

FILTER SAND** LBS KGS

0.45-0.55 500 227

*Based on 20 GPM/ft.2or 814 LPM/m2(maximum allowable NSF rating).

**Also known as No. 20 or No. 1/2 Silica Sand.

PARTS

Model S310T

REF.

NO.

1a

1b

2

3

4

5

8

9

10

11

SP071113

SP071620

ECX27081

GMX600F

SX310N

SX202S

SX310HA

SX180G

SX180H

SX310J

PART NO.

DESCRIPTION

Vari-Flo Control Valve - 1-1/2”

Vari-Flo Control Valve - 2”

Pressure Gauge

Valve/Tank O-Ring

Flange Clamp (Valve - Tank)

Sand Shield

Filter Tank with Skirt,
Drain and Lateral Ass’y.

Lateral Assembly with
Center Pipe

Lateral

Gasket

Drain Cap

Filter Support Stand (Skirt)

6

7

SX310DA

SX310AA1

NO.

REQ’D.

1

1

1

1

1

1

10

1

1

1

1

1

Loading sand media. Filter sand media is loaded through
the top opening of the filter.

Loosen flange clamp and remove Filter Control Valve
(if previously installed).

Cap internal pipe with sand shield to prevent sand
from entering it. Be sure pipe is securely in place in
bottom underdrain hub.

We recommend filling tank approximately 1/2 way with
water to provide a cushioning effect when the filter
sand is poured in. This helps protect the underdrain
laterals from excessive shock. (Be sure the winter
drain cap is securely in place on drain pipe).

Carefully pour in correct amount and grade of filter
sand, as specified. (Be sure center pipe remains
centered in opening). Sand surface should be leveled
and should come to about the middle of the filter tank.
Remove sand shield from internal pipe.

Assemble Filter Control Valve to filter tank.

Place stainless steel valve flange clamp around neck
of tank. Do not tighten. Wipe filter flange clean.

Insert Filter Control Valve (with valve/flange O-ring in
place) into the tank neck, taking care that the center
pipe slips into the hole in the bottom of the valve.
Place clamp around valve flange and tank flange just
enough so that the valve may be rotated on tank for
final positioning.

Carefully screw pressure gauge, with pipe tape, into
1/4” tapped hole in valve body. Do not overtighten.

Connect pump to control valve opening marked PUMP
according to instructions. After connections are made,
tighten valve flange clamp with screwdriver, tapping
around clamp with screwdriver handle to help seat
valve flange clamp.

Make return to pool pipe connection to control valve
opening marked RETURN and complete other necessary
plumbing connections, suction lines to pump, waste, etc.

Make electrical connections to pump per pump
instructions.

To prevent water leakage, be sure winter drain cap is
securely in place and all pipe connections are tight.

INITIAL START-UP OF FILTER

Be sure correct amount of filter sand media is in tank and
that all connections have been made and are secure.

Depress Vari-Flo control valve handle and rotate to
BACKWASH* position. (To prevent damage to control
valve seal, always depress handle before turning.)

Prime and start pump according to pump instructions (be
sure all suction and return lines are open), allowing the
filter tank to fill with water. CAUTION: All suction and

discharge valves must be open when starting the
system. Failure to do so could cause severe
personal injury and/or property damage. Once water

flow is steady out the waste line, run the pump for at least
2 minutes. The initial backwashing of the filter is
recommended to remove any impurities or fine sand

particles in the sand media.
Turn pump off and set valve to RINSE position. Start
pump and operate until water in sight glass is
clear—about 1/2 to 1 minute. Turn pump off, set valve to
FILTER position and restart pump. Your filter is now
operating in the normal filter mode, filtering particles from
the pool water.
Adjust pool suction and return valves to achieve desired
flow. Check system and filter for water leaks and tighten
connections, bolts, nuts, as required.
Note the initial pressure gauge reading when the filter is
clean. (It will vary from pool to pool depending upon the
pump and general piping system). As the filter removes
dirt and impurities from the pool water, the accumulation
in the filter will cause the pressure to rise and flow to
diminish. When the pressure gauge reading is 8-10 PSI
(0.55-0.69 BAR) higher than the initial “clean” pressure
you noted, it is time to backwash (clean) the filter (see
BACKWASH under Filter Control Valve Functions.)

NOTE: During initial clean-up of the pool water it may
be necessary to backwash frequently due to the
unusually heavy initial dirt load in the water.

IMPORTANT: To prevent unnecessary strain on piping
system and valving, always shut off pump before
switching Filter Control Valve positions.

To prevent damage to the pump and filter and for proper
operation of the system, clean pump strainer and skimmer
baskets regularly.

FILTER CONTROL VALVE FUNCTIONS

FILTER—Set valve to FILTER for normal filtering. Also use for

regular vacuuming.
BACKWASH—For cleaning filter. When filter pressure gauge

rises 8-10 PSI (0.55-0.69 BAR) above start-up (clean
pressure):
Stop the pump, set valve to BACKWASH. Start pump and
backwash until water in sight glass is clear. Approximately 2
minutes or less depending on dirt accumulation. Proceed to
RINSE.

RINSE—After backwashing, with pump off, set valve to RINSE.
Start pump and operate for about 1/2 to 1 minute. This ensures
that all dirty water from backwashing is rinsed out of the filter to
waste, preventing possible return to the pool. Stop pump, set
valve to FILTER, and start pump for normal filtering.

WASTE—To bypass filter for draining or lowering water level
and for vacuuming heavy debris directly to waste.

RECIRCULATE—Water is recirculated through the pool
system, bypassing the filter.

CLOSED—Shuts off flow from pump to filter.
VACUUMING—Vacuuming can be performed directly into the

filter. When vacuuming heavy debris loads, set valve to
WASTE position to bypass the filter and vacuum directly out to
waste.

*NOTE:For new concrete or gunite pools, or where there is a large amount of plaster dust or debris—start filter in FILTER position (not BACKWASH) to prevent clogging of

underdrain laterals.

3.
a.

b.

c.

d.

4.
a.

b.

c.

d.

5.

6.

7.

1.

2.

3.

4.

5.

6.

WINTERIZING

Completely drain tank by unscrewing drain cap at base
of filter tank. Leave cap off during winter.

Depress V ari-Flo control valve handle and rotate so as to
set pointer on valve top between any two positions. This
will allow water to drain from the valve. Leave valve in
this “inactive” position.

PLEASE REALIZE. . .

Pure, clear swimming pool water is a combination of two
factors—adequate filtration and proper water chemistry
balance. One without the other will not give the clean water
you desire.

Your filter system is designed for continuous operation.
However, this is not necessary for most swimming pools.
You can determine your filter operation schedule based on
your pool size and usage. Be sure to operate your filtration

Drain and winterize pump according to pump instructions.

SERVICE & REPAIRS

Consult your local authorized

Hayward

dealer or service
center. No returns may be made directly to the factory
without the expressed authorization of Hayward Pool
Products, Inc.

system long enough each day to obtain at least one
complete turnover of your pool water.

To properly sanitize your pool, maintain a free chlorine level
of 1 to 3 ppm and a pH range of 7.2 to 7.6. Insufficient
chlorine or an out of balance pH level will permit algae and
bacteria to grow in your pool and make it difficult for your
filter to properly clean the pool water.

3.

1.

2.

PROBLEM SOLVING LIST

LOW WATER FLOW SHORT FILTER CYCLES POOL WATER WON’T CLEAR UP

Check skimmer and pump
strainer baskets for debris.

Check for restrictions in
intake and discharge lines.

Check for air leak in intake
line (indicated by bubbles
returning to pool).

Backwash filter.

Check for algae in pool and
superchlorinate as required.

Be sure chlorine and pH
levels are in proper range
(adjust as required).

Check surface of filter sand
for crusting or caking
(remove 1” of sand if
necessary).

Check chlorine, pH and total
alkalinity levels and adjust
as required.

Be sure flow rate through
filter is sufficient.

Operate filter for longer periods.
Be sure Vari-Flo valve is set

on “Filter” position.

1.

2.

3.

4.

1.

2.

3.

1.

2.

3.

4.

REMEDY

POOL CHEMISTRY GUIDELINES

ACTION REQUIRED TO CORRECT POOL CHEMISTRY

TO RAISE

TO LOWER

SUGGESTED POOL CHEMISTRY LEVELS

pH
TOTAL ALKALINITY
CHLORINE (UNSTABILIZED)
CHLORINE (STABILIZED)

CHLORINE STABILIZER
(Cyanuric Acid)

7.2 to 7.6

100 to 130 ppm

0.3 to 1.0 ppm

1.0 to 3.0 ppm
40 to 70 ppm

Add Soda Ash
Add Sodium Bicarbonate
Add Chlorine Chemical
Add Chlorine Chemical

Add Stabilizer

Add Muriatic Acid or Sodium Bisulphate
Add Muriatic Acid
No action - chlorine will naturally dissipate
No action - chlorine will naturally dissipate

Dilution - partially drain & refill pool with water
that has not been treated with Cyanuric Acid.

©1999 Hayward Printed in U.S.A.

Rev. 6/99 A