I have an aquacal tropical t115 and a 22,000 gallon pool. Last night the pool was 73.9 deg when I turned the heat pump on at 10pm. This morning at 7 am the temp has only risen to 75.4 deg, so that's 1.5 deg in 9 hours. The air temp last night got down to 52 deg. Baes on the spreadsheet from acuacal's website, this heat pump should manage 2 hrs/degree when the air temp is below 60. Is this expected performance?
How long should my heat pump take
- Thread starter BlueWRXPride
- Start date
Is the pool covered ? Even if so, the cover only stops the evaporation heat loss, which is 70% or so.
Ok GREAT. Then your set up for your best chances, but still need the weather to cooperate
The HP calculator is kinda like MPG ratings on new cars. Sure you could get 39 MPH on the highway with textbook conditions of 55mph and the cruise control on, but when traffic is doing 74 mph and that stretch of highway is uphill...... you're getting 20 mpg.
In this case, you're likely making about what you should, but are losing most of what you produce.
The HP calculator is kinda like MPG ratings on new cars. Sure you could get 39 MPH on the highway with textbook conditions of 55mph and the cruise control on, but when traffic is doing 74 mph and that stretch of highway is uphill...... you're getting 20 mpg.
In this case, you're likely making about what you should, but are losing most of what you produce.
Perhaps I should consider that without the heat running, I lose about 3 degrees overnight. So in that case the heat pump really gained me 4.5 deg in 9 hours. Still well short of the rated "MPG" however.
Makes me wonder if it's even worth running it at night, even with electricity being a third or quarter the cost of during the day.
Makes me wonder if it's even worth running it at night, even with electricity being a third or quarter the cost of during the day.
Do you have a variable speed pump? I had a duh moment when I was complaining about the pump not heating that fast then my one 9 year old said dad doesn’t the pump slow down later in the day. I run it at 1800 from 4pm to 7am. While enough to run the heater the water was just not moving at an ideal rate.
- Jun 7, 2017
- 9,224
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
Humidity also plays a big part with heat pumps. At 52 degrees I would be surprised if your heat pump added a single degree.
My 400k BTU gas heater barely adds 2 degrees per hour. There is no way that heat pump will ever do that. I'd call that claim a flat out lie.
My 400k BTU gas heater barely adds 2 degrees per hour. There is no way that heat pump will ever do that. I'd call that claim a flat out lie.
I do, and I have it running faster at night. Still, I think that slower vs fast is largely a wash; either you have more water coming out at a less warm temperature, or less water coming at a higher temp.
- Jan 7, 2012
- 1,544
- Pool Size
- 21000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
It is. The heater will add xxx BTU/hr into the water whether the water flows through it fast or slow. The heater doesn't care as long as the pressure/flow switch is closed. Run your VSP at the slowest speed that still achieves your goals.
You have a 112K BTU (on a very good day) heater which will raise 112K pounds of water 1 degree per hour. Unfortunately you have about 176K pounds of water you're trying to heat. If your heat pump was working at its peak operating ability, based on temperature and humidity, it would have put just over 1,120,000 BTUs into the water in 10 hours and it would have raised the temperature about 6 degrees. In a laboratory that might happen. In the real world, not so much.
Ok, general take-away is that this is not an unexpected level of performance. Just wanted to make sure nothing was wrong. It makes me doubt the benefit of running it at night, but I'm guessing that for a heat pump, it's most efficient to set it to a temperature and just let it sit there and manage itself.
- Jun 7, 2017
- 9,224
- Pool Size
- 29000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Jandy Aquapure 1400
If it drops below 60 at night I would not bother running it.
In terms of energy efficiency, it is best to run the heat pump when the ambient conditions are warmer, so during the day will be best (however if electricity prices are significantly lower at night, as you suggested is the case for yourself, it is likely cheaper to run it overnight).
I have a heat pump too, and only run it during the daylight hours (but I have solar PV, so electricity costs are much less in the daytime for me). The only downside is that the pool is cooler in the morning than it would otherwise be if I left it running 24/7. But given the cost savings, that is something I'm prepared to deal with.
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