How to Winterize a Hayward Bottom Drain in a Swimming Pool
- 1). Open the valve on the main drain to allow air to bubble up from the drain for approximately 45 seconds. This purges air from the drain, which could expand during freezing temperatures.
- 2). Close the valve on the drain rapidly to stop the flow of air through the drain.
- 3). Remove the strainer from the cover by spinning it off the drain.
- 4). Thread the plug into the drain to block water flowing through the drain.
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