We are having an unseasonably warm September, which extends our very short swimming season. I'm curious to others' actual experience with heat pumps, specifically at what point does the outside temperature become low enough that they no longer are effective in prolonging the season. The manual for mine suggests it will function down to 50 degrees, but that seems ridiculously low to be truly feasible. We're still high 70s to mid 80s daytime, dipping closer to 60 overnight, and it is keeping up, but I'd like to know when to give up. This is only my second season, and last September was so brutally cold we were shut down in no time.
Heat pump operating temperature minimum
- Thread starter TDK_WPG
- Start date
- May 3, 2007
- 18,065
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
More than likely, the decision to stop running the HP is going be an economic one.
As air temperature drops, the BTU/hr of the HP will also drop but the heat loss (BTU/hr) of the pool water will increase so the HP will need to run longer as temperature drops to maintain the same water temperature. When air temperatures get low enough, it will be running 24hrs per day and water temperatures will still be dropping while costing you a fortune. The real question is where is your threshold of pain. It may end up being well before 50F.
As air temperature drops, the BTU/hr of the HP will also drop but the heat loss (BTU/hr) of the pool water will increase so the HP will need to run longer as temperature drops to maintain the same water temperature. When air temperatures get low enough, it will be running 24hrs per day and water temperatures will still be dropping while costing you a fortune. The real question is where is your threshold of pain. It may end up being well before 50F.
- May 3, 2007
- 18,065
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
I don't know this helps but I used typical heat loss values for your size pool, a pool temperature target of 82F, dew point offset of 9F, and the performance numbers for your HP and created a chart to show heat loss vs HP heat gain. The second chart shows HP run time to maintain the 82F set point.
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How do you determine how Mean the temperature is?
Can you post the graph for the Nice and Friendly temperatures or do you only use the meanest temperatures?
Can you post the graph for the Nice and Friendly temperatures or do you only use the meanest temperatures?
- May 3, 2007
- 18,065
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
All air temperatures below the water temperature are mean in my book. Getting out of the pool is not great experience.
Sadly in my northern clime that would cut my season in half from 16 weeks to about 8. Makes warm robes a must outside the pool!