DISINFECTION OF THE WATER
Even though the water is clear and transparent, it can contain within it bacteria and viruses which transmit diseases and infections. For this reason, it must be disinfected in order to eliminate all the microorganisms present in it. When chlorine is added to the swimming pool water, part of it is used up for destroying the contaminants that are in the water. The remainder stays in the water as residual chlorine, ready to act against all those this residual disinfectant is called Free Residual Chlorine. To ensure correct disinfection of the swimming pool water, the level of Free Residual Chlorine must be maintained between 0.5 and 2 ppm. Chlorine consumption varies with temperature, the amount of sunshine, the number of bathers, the pollution. For this reason, it is necessary to analyze the chlorine level daily with the aid of a chlorine and pH analyzing kit.
Prevention of algae
Algae are single-cell plant organisms which can develop and multiply rapidly in the water, especially when its temperature is lukewarm. The algae spores are introduced into the water by the wind, the rain, etc. To prevent their procreation, in addition to disinfectant, an anti-algae product must be used.
The pH is a very important factor as it has an influence on the disinfecting action of the chlorine, the comfort of bathers and the state of the facilities. The pH indicates the acidity or basicity of water. In a swimming pool, it must be kept adjusted between the values 7.2 – 7.6. In addition to keeping the facilities in an optimal state, this pH range is ideal for bathers’ skin and eyes.
The pH should be kept within that range because: when it is greater than 7.6 the disinfectant loses effectiveness and deposits can form in the facilitines, including hardness of the filter; if the pH is less than 7.2 corrosions can occur in the metal parts of the facilities as well as irritation of bathers’ eyes.
To keep it within these two values, analyze the pH daily with a chlorine and pH analyzing kit. If the pH is greater than 7.6, add DRY ACID to the water. If the pH is less than 7.2 add pH MINUS (ALKALI) to the water.
PUTTING THE SWIMMING POOL INTO SERVICE
At the start of the season, the swimming pool must be put into service. It is important to follow the appropriate procedures in order to avoid problems during the bathing season.
- Check that the equipment in your swimming pool (pump, filter, etc.) are functioning correctly
- Once the basin is clean, fill the swimming pool.
- Perform a shock chlorination with DICHLOR (200gr. For each 100m3 of water) or with CHLOR TABLETS. If your swimming pool takes longer than one day to fill up, it is recommended to proportion the product DICHLOR or the CHLOR TABLET during the filling to prevent algae formation during the operation.
- Analyze the pH of the weather and if necessary adjust it between 7.2 and 7.6 with acid or alkali.
- Apply the maintenance programme.
The secret of maintaining your swimming pool in a perfect state is to implement correct prevention treatment. To do so the following must be carried out:
- Analyze the pH of the water and adjust it between 7.2 – 7.6 if necessary.
- Analyze the level of free residual chlorine, keeping it between 0.5 and 2 ppm. If you use a proportioner, adjust it so that this chlorine residue is maintained.
- Clean the water of leaves and insects.
- Clean the skimmers and brush the walls of the basin. Next pass the bottom cleaner.
- Clean the filer in the reverse direction and clean the pump pre filter.
- Replace the trichlorine compacts of the skimmer or the proportioner.
- Add the maintenance amount of your anti-algae product.
1.Keeping the water level correct.
2.When you add new water to the swimming pool, analyze the chlorine and pH level and if necessary adjust them.
3.When rain threatens, increase the chlorine and anti-algae levels.
4.Check the chlorine proportioner and maintain its correct functioning.
SPECIAL PROBLEMS IN THE SWIMMING POOL
When the water loses its clarity, it could be due to several causes:
Poor filtering. Treatment:
Check the filter, wash in the reverse direction and increase the filtering hours. If the cloudiness is still considerable, carry out a treatment with flock, which will transform the suspended particles that are making the water cloudy, into large particles which will be retained by the filter.
High pH Treatment:
Analyze the pH and adjust it with acid, to keep it between 7.2 and 7.6.
Excessive organic residues:
Treatment: See the section ” irritation of eyes and skin, and bad smells”.
Algae formation Treatment: See the section “Algae formation”
If algae have formed in the water of your swimming pool, treat them immediately, since the longer they are there, the more difficult it will be to remove them.
Case A-Presence of algae on the walls and the bottom, with the swimming pool water clean and transparent.
Treatment: With the filtering equipment off, carry out shock chlorination. To do so, use in:
Swimming pools made with a ceramic coating, trichlorine ,
Swimming pools made a with liner, vinyl, polyester or painted, dichlorine.
Immediately afterwards add antialgae and 3.5 It for each 100m3
It is important to proportion these products directly into the areas where algae have been noticed. Leave the products to act for about 8 hours. Then BRUSH-BRUSH-BRUSH the walls and bottom.
Remove the dead algae withe the bottom-cleaner, sending the water directly to the drain.
Case-B-Presence of algae on the walls and/or bottom, with the swimming pool water cloudy and garden.
Treatment: With the filtering equipment off, carry out shock chlorination with shock chlorine (3000 gr. For each 100mi of water) or liquid chlorine. Immediately afterwards add antialgae (3.5 It 100m3 of water). Then flock (21t for 100m3 of water) . Leave the products to act for about 8 hours. Then BRUSH-BRUSH-BRUSH the wall and bottom. Remove the dead algae with the bottom cleaner, sending the water directly to the drain. Then filter as many hours as are required to obtain clean and transparent water.
The coloring of the water may be of different types:
Green and transparent water:
Treatment: analyze the alkalinity and, if less than 80 ppm, add alkali enhancer in appropriate measurements to attain alkalinity between 120 and 150 ppm.
Green and cloudy water:
Presence of Algae
Treatment: See the section ” Algae formation”
Presence of iron or manganese in the water
Treatment: adjust the pH between 7.2 and 7.6.
Carry out a shock chlorination with dichlrine (200gr per 100m3 of water) and then flocculate with flock.( 2 It for each 100m3 of water). Leave the products to act for about 8 hours, after which remove the dirt deposits on the bottom with the aid of the bottom-cleaner, sending the water directly to the drain. Once this treatment has been carried out, add anti-scale once a week.
Stains appear in corrosive waters or those, which contain dissolved metallic ions, such as iron, copper or manganese.
Treatment: Adjust the pH between 7.2 and 7.6. Once a week add anti-scale to prevent new stains. In the case of persistent stains, you will have to empty the pool and clean the basin with surface deposit remover.
Deposits are formed by the precipitation of the calcic salt that the water contains. The deposits can produce whitish waters, rough surfaces, and calcification of the filter and reduction of the conduits. Treatment: Adjust the pH to between 71— 7.6. Treat the water with anti-scale once a week.
Irritation of the eyes and skin, and bad smells
pH out of adjustment
Treatment: Analyze the pH and adjust it between 7.2 — 7.6
Excessive organic residues ( oils, sweat, urine, etc.)
Treatment: Carry out a shock treatment with Chock chlorine.
OPERATING THE FILTER TO BACKWASH
The selector valve handle can be turned to one of six positions indicating the necessary operations for the correct running of the filter.
IMPORTANT: Always stop the pump before changing the selector valve position.
The pressure gauge will indicate the build up of dirt in the filter. At the start of the filtration process the pressure gauge will indicate approximately 0.8 kg/cm2 of pressure. As the filter becomes dirtier, the pressure increases. When said pressure reaches 1.3 kg/cm2 a backwash operation needs to be carried out.
The media bed forms thousands of channels become saturated with dirt the filter must be cleaned through backwash and the dirt sent to waste. As stated elsewhere, the pressure gauge gives an indication of the pressure accumulated in the filter as a direct result of the retention of particles in the media. When the pressure gauge indicates 1.3 kg/cm2 a backwash must be carried out in the following manner:
- Stop the pump .
- Place the selector valve handle in the position of backwash.
- Start the pump for a period of two minutes. (Check the sight glass on the selector valve to ensure water is clear).
This operation reverses the flow in the filter to fluidise the sand bed, releasing the dirty matter to waste.
After backwashing a rinse operation is recommended before the filtration mode is re-started to ensure that no turbid water is returned to the pool. To do this, stop the pump place the handle to rinse option, start the pump for 1 minute (check the sight glass on the filter as the exact time will depend on how dirty the water is). This operation flows in the same direction as the normal filtration option except that the water goes to waste and not back to the pool.
In this option the water from the pump will return straight to the pool without going through the filter.
If the pool dose not have a drain the pool may be emptied via the pump with the position of WASTE selected. Leave the main drain open, skimmer and vac, point valves must be closed in order to realize this operation.
As the name suggests this closes off the entry of the filter and is most normally used when access to the pump prefilter basket is required.
POOL TEST KIT – INSTRUCTIONS
PH DETERMINATION :
- Take the dear glass sample tube out of the comparator.
- Rinse the sample tube in dear water and fill to just below the bottom of the stopper.
- Add one test tablet from the PH packet. Replace stopper and shake.
- Place sample tube in the center comparator hole and read off against the permanent glass color standards. if the sample is below the lower limit, the water is too acid. if above the higher limit, the water is too alkaline.
To be carried out after PH determination.
- Wash out sample tube thoroughly.
- Refill sample test tube to just bellow the bottom of stopper.
- Add on DPD 1 test tablet. Replace stopper and shake.
- Match against permanent glass color standards. This indicates the amount of free chlorine.
N.B. DO NOT CONFUSE THE PH AND CHLORINE TEST TABLETS, ASS THE PACKETS ARE RATHER SIMILAR.
TO VACUUM :
- Remove vacuum plug from the point in wall.
- Immerse vacuum head (attached to pole) with the hose connected to the head, in the water. Feed rest of hose vertically into the water so that the water comes up through the hose until the hose is finally full of water.
- Connect the hose to the wall point with hose to wall fitting.
- Open vacuum valve, close skimmer valve.
- Start the close sump valve checking pressure gauge. If the pressure drops considerably, keep sump valve slightly open to balance flow.
- Vacuum the floor by moving the head backwords and forwords over the floor. Avoid packing up large objects, which may become blocked in the line.
- After vacuuming, it is necessary to check the strainer box basket in pump housing, which may have become closed up with leaves or other debris removed while vacuuming.
TO EMPTY STRAINER BOX BASKET
- Stop pump.
- Close all manifold valves, i.e. Sump, skimmer, vacuum, and inlet.
- Set sellection valve to ‘CLOSED’ position.
- Open strainer box lid by undoing bolts. Left out the basket and clear. At the same time you may check the impellar which is in line with the pump motor to make sure that it is clear of any obstruction i.e. hair, leaf stems, etc. By placing fingers in aperture and filling impellar.
- Replace basket and before replacing strainer box lid check the rubber seal of the lid and clear of grit. it is important to make a good seal otherwist the filter will draw air. The bolts on the strainer box should be finger tight.
- To continue fitter cycle open skimmer and sump as previously instruction and set selection valve on `Filter’ position.
- Start pump and test air release valve for air in filter drum. Release until water comes out and close.
N.B. IT IS IMPORTANT TO NOTE THAT THE VACUUM HEAD MUST NEVER BE LIFTED ABOVE WATER LEVEL; OTHERWISE IT WILL DRAW AIR INSTADE OF WATER. IN THE EVENT OF AIR BEING DRAWN INTO THE SYSTEM THE VACUUM SHOULD BE DISCONNECTED FROM THE WALL AND THE OPERATION REPEATED.
OPERATION: PLANT WITH 3-WAY MANIFOLD:
The three valves on the manifold control the suction from the pool as follows :
This controls the flow of water from the skimmer or skimmers to the filter. These are built into the pool wall at surface water level and the water is drawn over the small floating weir, thereby creating tension on the surface of the water, a certain amount of (leaves and surface dirt will be drawn into the skimmers. During normal filtration periods this valve should be fully open.
SUMP VALVE (MAIN DRAIN)
This controls the flow of water from the sump to the filter. The sump itself is situated in the floor of the pool at the deep end. its purpose is to draw off water at the deepest part of the pool, thereby increasing all round circulation. However, its main function is for emptying the swimming pool, if ever necessary. During normal filtration periods this valve will be partly open. This enables the main suction to be on the skimmer line.
This controls the flow of water from the vacuum point to the filter. The vacuum point is situated in the pool wall. The vacuum valve should be closed during periods of normal filtration. Before the vacuum valve is opened, the plug in the wall should be removed. This can be left out during periods when the pool is in constant use. In order to effect the operation of the vacuum cleaner, see instuction ‘OVER LEAF’.
BALANCE TANK VALVE
This controls the over flow to the filter. The overflow system of the pools always have a balance tank to balancing the over flowing when the filtration is working always must be top upping the water in balance tank to circulate the water for over flowing.
After the commissioning, the plant will be flittering water by the following process :
The water is drawn from the pool through the manifold and into the pump housing. in the pump it passes through a strainer box which prevents any large objects from fouling the pump impeller, driven by the electric motor, then drives the water through the variflow valve which is set on the ‘filter’ position. The water passes through the stainless steel fitter drum under pressure. Half of the drum is filled with Silica sand and the water has to pass through the sand and in so doing the water is purified. The water then returns to the pool via the inlets in the pool walls. If some form of heating is installed, then the water will be heated after it has been filtered and then returned to the pool.
The pressure in the filter drum is recorded by the pressure gauge on top of the drum. The initial pressure should be noted. Over a period of time, and this various according to bathing loads etc. the pressure in the drum will increase. This is due to the build up of dirt on the sand. The flow rate of water through the fitter is reduced as the pressure increases. When the pressure reaches 5-7 lb. Over the initial pressure, then the filter needs to be cleaned. This will call ‘backwashing’.