Heat pump takes forever to warm pool in the morning.
- Thread starter Isabella
- Start date
Zephyr
Member
Also depends on air temp. If mornings are cool the unit won’t be as efficient. Covering the pool overnight helps hold the heat you gained the day before.
Freddie
Member
Yeah heat pumps are slower than gas heaters. They work best if you keep the temp steady instead of trying to raise it a bunch all at once.
Isabella
Member
Got it, I’ve been turning it off at night so that’s probably why it feels like it’s always starting from scratch. I’ll try leaving it steady and use the cover more.
Robert Smith
Member
That’s pretty normal for a heat pump. They’re designed to maintain temperature rather than heat water super fast like a gas heater. Using a pool cover overnight and keeping the pump running at a steady speed helps it retain heat and reduces how long it takes to reach your target temperature in the morning.
I’m new to this industry. I’m not always at the house with the swim spa, it arrived before me. So when the temp drops in the spa this guage will notify me. However, I’m terrified to keep it in the spa bc I think it will melt. Anyone know anything about these? How safe they are? Last summer my heater went out after Xmas.
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Jacob Foster
Member
Isabella, totally normal. Mine was the same way when I first got it, and I thought something was wrong too. Heat pumps just work differently, they pull warmth from the air, so on cool mornings, they’re basically running uphill until the air temp rises a bit.
I leave mine running overnight now and use a solar blanket, and it makes a big difference. Instead of taking all morning to climb a few degrees, it’s already close to my set temp when I wake up. Once you get into that rhythm, it’s a lot less frustrating.
I leave mine running overnight now and use a solar blanket, and it makes a big difference. Instead of taking all morning to climb a few degrees, it’s already close to my set temp when I wake up. Once you get into that rhythm, it’s a lot less frustrating.
John Harrison
Member
Yeah, that’s pretty much how heat pumps behave, especially early in the day when the air’s still cool. Mine used to drive me nuts at first, I’d check the temp every hour thinking something was wrong. Once I started running it overnight and threw on a solar cover, it made a huge difference.
Now, it might only drop a degree or two overnight, and by mid-morning it’s already back to temp. Heat pumps just work best when you let them maintain instead of “catch up.” If you shut it off completely, it’s like asking it to climb a hill from the bottom every morning.
So yeah, what you’re seeing is normal, just part of getting used to how they heat.
Now, it might only drop a degree or two overnight, and by mid-morning it’s already back to temp. Heat pumps just work best when you let them maintain instead of “catch up.” If you shut it off completely, it’s like asking it to climb a hill from the bottom every morning.
So yeah, what you’re seeing is normal, just part of getting used to how they heat.
John Smith
Member
Hey Isabella, what you’re noticing is pretty common with heat pumps. Unlike gas heaters that blast heat quickly, heat pumps rely on the air temperature to warm the water, so mornings, when the air is cooler, are always slower. One thing that helps a lot is running the pump consistently and keeping a pool cover on overnight.
That way, the heat you gained the day before doesn’t escape, and the pump isn’t trying to start from cold every morning. Also, if you can, avoid shutting it off completely; maintaining a steady temperature is far more efficient than letting it drop and trying to “catch up” each day.
That way, the heat you gained the day before doesn’t escape, and the pump isn’t trying to start from cold every morning. Also, if you can, avoid shutting it off completely; maintaining a steady temperature is far more efficient than letting it drop and trying to “catch up” each day.
Henry Thompson
Member
Totally normal, Isabella. Heat pumps work kind of like the “slow and steady” option, they don’t blast heat, they build it gradually. Mine used to feel the same way in the mornings until I stopped shutting it off overnight. Once I let it maintain temperature instead of starting from cold each day, it stopped taking forever to warm up.
If you can, throw on a solar or thermal cover too, it traps a surprising amount of heat overnight. That way, when you wake up, the water’s already close to your set temp, and the pump doesn’t have to work as hard. Heat pumps really shine when they’re allowed to maintain heat rather than chase it.
If you can, throw on a solar or thermal cover too, it traps a surprising amount of heat overnight. That way, when you wake up, the water’s already close to your set temp, and the pump doesn’t have to work as hard. Heat pumps really shine when they’re allowed to maintain heat rather than chase it.
Andrew Coleman
Member
Most of the answers here are solid, but one thing that helped me wrap my head around it was actually timing when the heat pump is doing its real work.
On mine, the morning hours were basically the worst possible window. Cool air, cold water, and the unit running flat out just to tread water. The big gains didn’t start until late morning or early afternoon when the air temp climbed and the coil wasn’t fighting dew or cool humidity anymore. That’s when I’d finally see a steady 1 to 2 degree bump over a few hours. Before that it felt like nothing was happening, which made it seem broken.
Another factor is water movement. If the pump is on a lower speed in the morning, the heat pump can’t transfer heat efficiently, even if it’s technically “on.” I noticed better results once I bumped the pump RPM during heating hours and let it drop back down later. Filter pressure stayed stable, but the heat pickup was noticeably better.
If you want to sanity check it, watch how many degrees it gains between noon and sunset versus early morning. If it heats faster later in the day, that’s just how heat pumps behave, not an underperforming unit.
On mine, the morning hours were basically the worst possible window. Cool air, cold water, and the unit running flat out just to tread water. The big gains didn’t start until late morning or early afternoon when the air temp climbed and the coil wasn’t fighting dew or cool humidity anymore. That’s when I’d finally see a steady 1 to 2 degree bump over a few hours. Before that it felt like nothing was happening, which made it seem broken.
Another factor is water movement. If the pump is on a lower speed in the morning, the heat pump can’t transfer heat efficiently, even if it’s technically “on.” I noticed better results once I bumped the pump RPM during heating hours and let it drop back down later. Filter pressure stayed stable, but the heat pickup was noticeably better.
If you want to sanity check it, watch how many degrees it gains between noon and sunset versus early morning. If it heats faster later in the day, that’s just how heat pumps behave, not an underperforming unit.
Tanvi Yadav
New member
That’s actually pretty typical from what I’ve seen. A heat pump usually raises the temperature gradually, especially if the starting water is cool. I noticed mine felt slow at first too, but once I stopped shutting it off overnight and kept heat loss under control, the gains became more noticeable and consistent.
Nathan Parker
Member
I thought mine was underperforming the first season too. I’d go out at 8 am, see it running, and by noon it felt like nothing had changed. Super frustrating.
What helped was actually measuring instead of guessing. I used the same thermometer in the deep end at 9 am and again at 3 pm. On a 65 to 70 degree air day, I was only gaining about 1 degree by late morning, but between noon and 5 pm it would jump 2 to 3 degrees. Heat pumps really depend on air temp and coil conditions, so mornings are basically their weakest hours.
Also check your flow. When my filter pressure climbed from 14 psi to around 18 psi after some debris buildup, the temperature rise at the return dropped noticeably. It was still heating, just less efficiently. Once I cleaned the filter and kept the pump at a steady RPM during heating hours, performance improved.
And like others said, shutting it off overnight makes it feel worse. If the pool drops 4 to 5 degrees overnight due to evaporation and cool air, you’re asking the heat pump to climb that hill every single morning. With a cover, mine only drops 1 to 2 degrees, and the unit feels way more “capable.”
If you’re seeing a small but steady gain during the warmest part of the day, it’s probably normal behavior. If there’s almost no temperature difference between the inlet and outlet water even in decent air temps, that’s when I’d start questioning performance.
What helped was actually measuring instead of guessing. I used the same thermometer in the deep end at 9 am and again at 3 pm. On a 65 to 70 degree air day, I was only gaining about 1 degree by late morning, but between noon and 5 pm it would jump 2 to 3 degrees. Heat pumps really depend on air temp and coil conditions, so mornings are basically their weakest hours.
Also check your flow. When my filter pressure climbed from 14 psi to around 18 psi after some debris buildup, the temperature rise at the return dropped noticeably. It was still heating, just less efficiently. Once I cleaned the filter and kept the pump at a steady RPM during heating hours, performance improved.
And like others said, shutting it off overnight makes it feel worse. If the pool drops 4 to 5 degrees overnight due to evaporation and cool air, you’re asking the heat pump to climb that hill every single morning. With a cover, mine only drops 1 to 2 degrees, and the unit feels way more “capable.”
If you’re seeing a small but steady gain during the warmest part of the day, it’s probably normal behavior. If there’s almost no temperature difference between the inlet and outlet water even in decent air temps, that’s when I’d start questioning performance.