Depends on how much you heat, outside air temperatures, whether or not you have a cover, etc.
We ended up putting in a heater after we bought our home. Pool is in the shade most of the day, and the water temp never really got above 76 degrees. Sounds nice and refreshing, but we like warm water
. Figure about $2500 or so for a gas heater plus plumbing costs to run your gas line to the heater. You may also need a larger gas meter.
In the summer, we tend to keep the pool at about 82-84 (outdoor day temps in the upper 80's-low 90's). That adds about $100/ month to our gas bill. In cooler weather, it can get up up about $300-400/month (yes, ouch). We don't have a pool cover though...
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Daki/ Opossum/ Rosemary/Shashi/ Dakiri
