Closing the Pool

Winterising - preparing the Pool for Winter

If you have not winterised your pool before, now is your chance to save some money!

'Winterising', in this sense, means to prepare the pool for the winter.

By following the instructions below you will be able to turn the pump, and any other electrically operated pool-equipment, 'off' for the whole of the winter except for a monthly application of pH reducer if required .

This has a few added benefits other than the obvious reductions in utility and chemical bills. Winterising chemicals are approx. €40.00 for the entire winter but this cost is more than offset by savings on electricity. The average private pool owner will be about €150 better off by winterising the pool. (And you won't have to clean it every week!)

An average private pool will use roughly 20m³ of water to back-wash the filter over a winter - but nothing at all if the pool is winterised!

If your PumpChlorinator, Filter, etc. are running for only half of the year then the equipment is likely to last for twice as many years, saving lots of money!

How to Winterise your pool

  • Remove the summer pool-cover, clean it, rinse it, dry it thoroughly and store it in a dry place
  • Clean the pool and adjust the pH if required - but do not add Chlorine* see note below
  • Place one cube of Jolly Gel in the pump basket and run the filter for 24 hours

           Note:-  Using Jolly Gel in this way will ensure that the water and the filter begin their winter 'hibernation' in the best possible condition; greatly reducing the chance of an expensive disaster.

  • The following day, clean the pump pre-filter basket and thoroughly clean the filter by carrying out an extra-long backwash - see full instructions below: -
  • Close the 'Skimmer' and 'Jets' valve, open the 'Bottom Drain' and 'Waste' valves, turn the rotary valve to 'Backwash'.
  • Turn the pump on and backwash the filter continuously until the water level has dropped to 15cm (6") below the entrance to the skimmers, rinse the filter, then close the 'Waste' valve. The winter rains will re-fill the pool and reduce Total Dissolved Solids
  • Don’t drop the level more than this because, if the natural water table is high, this could present structural hazards.
  • Add a proprietary winterising treatment. These treatments are designed to inhibit algae growth and minimise the risk of mineral staining (Winterising fluid is a mixture of Ammonia and Copper Sulphate). In Spain it is called Invernador and is available at every pool-shop and most ferreterias. TIP: - Don't buy a cheap winteriser: get a good brand.
  • Open the 'Jets', 'Bottom Drain' and 'Waste' valves, turn the rotary valve to 'Circulate' and turn the pump on to mix the solution into the pool water
  • If there is a possibility of frost, drain the water from the filter, pump, pool-heater and pipe-work.
  • Grease any exposed metal surfaces with silicone grease, lithium grease or Vaseline.
  • Valves that are above the water level should be left open; those below should be closed and protected against frost damage
  • Remove ladders, diving boards and summer covers, toys, floats etc., clean them and store them away
  • Switch off the electricity supply to the pool equipment at the Control Box
  • Turn the electrical breakers off or remove the fuses and store them in the Control Box so that you will be able to find them next Spring or when you need to run the pump to adjust pH
  • If frost is a possibility, float one or two weighted polythene containers or coca-cola bottles in the pool to absorb the expansion of ice
  • Remove leaves from the cover or the pool throughout the winter period
  • Check the pH and the appearance of the water each month during the winter, especially as spring approaches or if the winter is mild.  Remedy as required and note everything you do to the pool in your Logbook

*Do not add Chlorine during the winter because it will destroy some of the ammonia in the winterising fluid


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Ken Walker - MyPoolGuru©