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Winterizing In-Ground Softswim Pools

Follow these Steps


Ultra Modern Pool & Patio does not recommend draining any pool for the winter because the pool walls are not strong enough to withstand earth pressures brought on by freezing of the earth and hydrostatic water. When a pool is empty, hydrostatic water can collapse pool walls that are not properly braced or reinforced or even possibly float the pool out of the ground. Gunite pools (steel reinforced, air placed concrete against the earth), are anchored to the ground and are less likely to float than any other pool when empty. Since outside pressures on the pool structure do exist, it is recommended that water be kept in the pool year round. Vinyl liners can shrink and suffer wind damage when left empty.

Following are the main steps in winterizing a pool. Since there are many different types of pools and equipment, it is impossible to give exact details. Some steps may or may not apply and therefore you should refer to your owner’s manual or contact your builder or Ultra Modern Pool and Patio before winterizing your pool.
Do not winterize until your pool water temperature is 58-60 degrees. Generally, sometime later in September or early October is acceptable.
Ultra Modern Pool and Patio recommends that all pools be covered with a solid or mesh cover for the winter. It is economical and an easy way to care for the pool in the off-season. The pool cover keeps debris and leaves out of the pool and protects the interior finish. A mesh tie-down cover is a safety factor when children and pets have access to the area. A solid tie-down cover or automatic cover should be kept free of water for safety.

Cover Tip: Keep the pool cover drained off and skim leaves periodically so the cover does not fall in due to the weight on the cover. Tucking the cover in against the inside wall of the pool will help hold the cover in place. Ultra Modern Pool & Patio offers several styles of Little Giant Pumps to pump off excess water. Use BioGuard® Stow-Away® to clean the cover and for storage and extend cover longevity. Automatic covers should be cleaned twice a year for longevity of vinyl.
Solar Cover: Clean with BioGuard® Stow-Away® before storing. Remember, never leave a solar cover on the pool for winter use. You can spray BioGuard® Stow-Away® on the cover as you fold it; leave on to prevent mildew and to extend cover longevity. Fold the cover accordion style for ease of reusing next spring.


STEP 1: Bring your pool to Ultra Modern Pool & Patio. Bring us a sample of your pool water for the end-of-season testing. You’ll get the prescription you need to prevent stains, scaling, damage to equipment and the recirculating system. Follow Ultra Modern Pool & Patio’s directions for application to properly balance your water for conditions in your area. You’ll avoid expensive cleanups and repairs. Come spring, you’ll start with a beautiful pool.
STEP 2: Brush and vacuum the pool to remove all algae, debris, and loose dirt. The pool should be free of algae before closing. You must kill all mustard algae before closing as this spore is ambient and can survive the winter. Do not close a pool with pink slime or white mold as it can be worse in the spring. Clean the water line with BioGuard® Alkaline Surface Cleaner® and/or BioGuard® Off the Wall Cleaner®.
STEP 3: Add necessary balancing chemicals and let circulate for 8 hours. The water needs to be in complete balance. Improper water balance can cause damage to the pool finish. High calcium hardness, pH, and/or total alkalinity can cause scale and the liner may lose its plasticity and become stiff and brittle. A low calcium hardness, pH, and/or total alkalinity can wrinkle the liner and etch a plaster, concrete or fiberglass surface.
STEP 4: If using Proteam® Supreme or Optimizer Plus®™, make sure levels are at 50-80 ppm.
STEP 5: Add one quart of BioGuard® SoftSwim Stain Control® per 10,000 gallons and let circulate one hour minimum before adding BioGuard® SoftSwim “C” Clarifier®. We feel the investment you make now will save you money in the long run. When the pool water temperature drops, a chemical reaction creates scale fall out and a scale formation can form on the pool surface. BioGuard® SoftSwim Stain Control® will protect against scale formation. All plaster pools must use SoftSwim Stain Control® on opening and closing and should do maintenance doses during the pool season.
STEP 6: Backwash and clean the filter. Ultra Modern Pool & Patio recommends changing the sand at the end of every season since your filter will not be operating for several months. If this is not possible, use BioGuard® SoftSwim Filter Cleaner® to remove scale and debris from the filter. Never store a dirty filter, since deposits and scale may harden and cake over during the winter, leaving you a tough clean up job or repairs in the spring. Do not use BioGuard® Strip-Kwik® or BioGuard® Kleen-It®. (It is recommended to clean the filter once a month during the swim season.) Use BioGuard® SoftSwim Filter Cleaner® to clean the sand. DE and cartridge filters should be winterized per manufacturer’s recommendations.
STEP 7: The pool should be clear and holding a BioGuard® SoftSwim “C” Clarifier® level before going to step 8.
STEP 8: Add one quart of BioGuard® SoftSwim® “A” Algicide for every 25,000 gallons. Let circulate for one hour.
STEP 9: Add one gallon of BioGuard® SoftSwim “C” Clarifier® for every 10,000 gallons. Let circulate overnight.
STEP 10: Test your BioGuard® SoftSwim “B” Bactericide® level and add the proper amount to reach 50 ppm. One pint of Bactericide® for every 10,000 gallons of pool water should raise the level approximately 10 ppm.
STEP 11: All pools with automatic covers should be left full of water during the winter. The cover has to rest on the water or damage might occur to the cover. In pools with tile, the water should be 2” below the tile line to prevent damage to the tile from water freezing. Pools with standard covers may also be left full of water, follow same procedures as auto cover.
STEP 12: Let the pump run to circulate products for several hours.
STEP 13: To winterize – you can lower water level by running the filtration system on waste position until the desired water level is reached. You will need to plug the skimmer(s) or turn off the skimmer(s) valve. You are draining the pool through the main drain. If you do not have a main drain, you will need to lower the water level by a submersible pump. Lower the water level 6” below the skimmer. If the light is at water level, take out or lower water below the light. Return lines should be filled with antifreeze.

There are three different steps:
a) Unscrew return fitting (leave on faceplate – usually 2-4 screws), screw in PVC elbow (1 1/2 mpth x 1 1/2 s), sometimes extra pipe is necessary for extra length. Pour in antifreeze, leave pipe in and plug with winter plugs.

b) Blow out skimmer: blow from inlet on pump (hair and lint strainer pot – suction line) back to skimmer(s). If you have an auto cover, you need to keep your water level up, so use our G200 Blow Out Extension (available in our parts department). Screw it into the skimmer before blowing lines and cap the extension when lines are blown (leave in skimmer). If you don’t have an auto cover, lower your water level, blow the lines and use either size of our Gizzmo (trade name). The Gizzmo or blow Out Extension absorbs ice expansion and prevents freezing water from cracking the skimmer.

c) Blow out returns – blow out from the return line at your equipment (this would be after the pump filter, or heater and should be a union or no hub, if not cut line and blow and then use union or no hub in lieu of coupling) and plug the returns with winter plugs and add your antifreeze to the lines. For returns, start at the farthest one and work back to the closest return. Remove one plug at a time as you blow out. Add one gallon of antifreeze per 20 feet of pipe to each skimmer. If you do not want to use a Gizzmo, then you can use a quart plastic bottle with a little sand (for weight) in it or half full of antifreeze. If you have a vacuum line, drain, fill with antifreeze or blow it out.

STEP 14: Drain the filter by removing the plug or plugs located at the bottom of the filter tank. If the filter valve has a plug on it, remove it or place the valve between positions. Some valves have a winter position on them, if so, put the valve in this position. This allows the valve to drain completely. Shut off time clock and remove trippers.
STEP 15: Drain the pump by removing the drain plug or plugs. If the plug or plugs cannot be removed easily, add swimming pool antifreeze to pump strainer pot to avoid damage. Ultra Modern Pool & Patio’s service department prefers to add swimming pool antifreeze to the pump. Swimming pool antifreeze provides an important benefit, it keeps the seal lubricated and the pump will not be damaged by accidental start-ups. Drain the automatic cleaner booster pump and store the cleaner hoses straight and out of sunlight, preferably indoors.
STEP 16: Drain the pool heater by removing the drain plug or opening the drain cocks. Turn off the main gas supply to the heater. On some heaters it is necessary to disconnect the pressure switch from the 1/4” copper tubing, as it may contain water. Add antifreeze to heater u-shaped water traps. If they have a union connection, loosen and allow water to drain.
STEP 17: Remove the ladders, diving boards, baskets and all maintenance equipment and store them indoors if possible.
STEP 18: All valves should be left open. Ball valves should be 1/2 open and 1/2 closed.
STEP 19: Turn off breaker(s) going to the pump (if on separate breaker). There could be one outside by the equipment and another in the house.
STEP 20: Drain the water line to slide if you have one, and turn off water supply. Drain any lines to fountains and turn off the water supply.
STEP 21: Winterize the automatic water leveler if you have one, turn off the water supply and drain the line.
STEP 22: Turbo clean units or any other built in floor cleaning system. If you have one – drain turbo clean pot.
STEP 23: You are ready to cover the pool. Do not use a solar cover for winter closing.
STEP 24: Check under the cover monthly, more often in warm weather. Test BioGuard® SoftSwim “B” Bactericide® level and add top off dose if needed. Test BioGuard® SoftSwim “C” Clarifier® level and add more as needed.

Ultra Modern Pool & Patio offers a monthly service called Winter Watch – Call the Service Department for more information.
REMEMBER — Always follow your pool builder’s recommendations on lowering water levels and winterizing the plumbing.

NOTE: Always follow label directions and manufacturer’s instructions for each product used. Conditions may vary from pool to pool. Ultra Modern Pool & Patio does not assume any responsibility or liability for the results that may be obtained through utilization of this or any other program, procedure or product.

Tools/Equipment Required:
_____ Leaf net
_____ Pole
_____ Vacuum
_____ Pool Brush
_____ Submersible Pump

Tile Cleaning Products
_____ BioGuard® Off the Wall
_____ Scrub Pad

Filter Cleaning & Filter Aid Products
_____ BioGuard® Softswim Filter Cleaner
_____ BioGuard® Sparkle up
_____ BioGuard® Polysheen Blue
_____ BioGuard® Softswim Filter Aid

Winterizing Products:
_____ BioGuard® StowAway
_____ Winter Cover
_____ Water Bags
_____ Gal. Pool Antifreeze
_____ Winter plugs for return lines (#SP1022C) 1 1/2” threaded plugs
_____ Winter Blowout Ext. Gizzmo
_____ BioGuard® SoftSwim Stain/Metal Control
_____ BioGuard® Optimizer Plus


Bulletin #101