Astralpool 56936 Manuel D'instructions page 5

7.1 FILTRATION (FIG.7)
With the pump stopped set the valves to the position labelled filtration.
During the filter's normal operation, it is recommended to periodically
check the entrance and exit pressure gauges and carry out a backwash
when the difference in pressure is equal to or more than 0.8-1 kg/cm
In industrial applications the pressure difference should not exceed 0.6-
2
0.8 kg/cm .
Normally when referring to filtration for pools the entrance pressure
gauge shows a pressure of 0.8-1kg/cm
0.4-0.6 kg/cm 2 (standard pressure when the filter is clean).
As the filter gets dirty during its use, the entrance pressure gauge
experiences an increase in pressure at the same time as the exit
pressure gauge shows a fall in working pressure.
EXAMPLE
Entrance pressure gauge
Exit pressure gauge
Pressure difference
In this case it is necessary to backwash the filter.
7.2 BACKWASH (FIG.8)
The bed of sand inside the filter forms thousands of channels through
which the water flows and logically they collect impurities and solid
deposits that the water brings with it to the filter. In time these deposits
block the channels and it is periodically necessary to clean the filter to
leave it in optimum working condition and drain the dirt that had collected.
It is recommended to backwash with water for 7 minutes at a speed of 40-50 m
It is advised to place a sight glass in the drainage pipework so that during the backwash you can see the dirt leaving the filter and in this way
determine the duration of the backwash needed.
We recommend that backwash does not exceed 50 m
To carry out a backwash cycle, ALWAYS WITH THE PUMP SWITCHED OFF, set the valves to the backwash position indicated on the template.
7.2.1. BACKWASH WITH AIR AND WATER (ONLY FOR FILTERS WITH NOZZLE PLATES OR DOUBLE LATERALS)
Air is used to dislodge and agitate the sand bed. This makes the backwash process more efficient in less time and saves a substantial amount of
water.
This process is carried out in three phases:
• Inject air at a speed of approx. 60 m/h
• Inject water at a speed of approx. 50 m/h
• Inject water and air at a speed of no more than approx. 50 m/h
7.3 RINSING (FIG.9)
This operation is recommended straight after the backwash, in order to
expel any remaining deposits that had penetrated the collectors during
the backwash cycle.
This operation should last approx. 3 minutes and prevents cloudy water
returning to the pool.
To carry out this operation set the valves to the rinse position (ALWAYS
WITH THE PUMP SWITCHED OFF) and immediately afterwards reset
the valves to the filter setting.
The rinse position can only be applied if the battery has 5 valves.
7.4 DRAIN (FIG.10)
When it is necessary to empty the pool and in the case of not having the
drainage connected directly to the mains sewer system, you can empty it
using the filter pump by positioning the valves to the 'drain' section on the
template.
To do this and before commencing, the skimmer, overflow channel and
pool cleaner valves must be closed.
2 and the exit pressure gauge
1.4 kg/cm 2
2
0.3 kg/cm
2
1.1 kg/cm
3 /h/m 2 to avoid any sand being expelled into the drainage system.
OPEN
2
.
DRAINAGE
3 /h/m 2 .
DRAINAGE
DRAINAGE
4
EXIT
FIG.7
DIFFUSERS
THE POOL
COLLECTORS
FIG.8
DIFFUSERS
THE POOL
COLLECTORS
FIG.9
DIFFUSERS
THE POOL
COLLECTORS
FIG.10
FROM
FROM
FROM