If your AquaCal HeatWave SuperQuiet heat pump is running but the pool water is not getting warmer, do not assume the unit has failed. The issue may be mode settings, thermostat setpoint, water flow, valve position, heat loss, external controller setup, or realistic first heat-up expectations.
A common pool owner frustration is seeing the heat pump turn on, hearing the fan run, and still feeling like the pool is not getting warmer. With an AquaCal HeatWave SuperQuiet heat pump, that does not automatically mean the unit is broken.
Models like the AquaCal HeatWave SuperQuiet SQ140R and AquaCal HeatWave SuperQuiet SQ200R depend on the right operating mode, temperature setpoint, water flow, valve position, pump run time, and heat retention. If one of those is wrong, the heat pump can run without giving you the result you expect.
This guide breaks the troubleshooting process into homeowner-friendly steps so you can separate a true service issue from a setup, flow, or heat-loss problem.
Important: This article is a troubleshooting guide for pool owners. It does not replace the official AquaCal manual or professional service. Electrical, refrigerant, internal component, sensor, compressor, and control-board work should be handled by qualified professionals.
Quick Answer: Why Is My AquaCal SuperQuiet Running But Not Heating?
If your AquaCal SuperQuiet is running but not heating the pool, start with these checks: confirm Heat Mode, set the thermostat above current water temperature, make sure valves are positioned to heat the correct pool or spa, confirm there are no error codes, verify filter pump run time and water flow, reduce heat loss from water features or air blowers, and check whether the discharge air is colder than the outdoor air.
Wrong mode or setpoint
The unit may be running, but not calling for heat if the mode or thermostat setting is wrong.
Valve or controller issue
Water may not be routed through the correct body of water, or an external controller may not be set correctly.
Heat loss is overpowering gain
Waterfalls, spa spillovers, air blowers, wind, cool nights, and no cover can make heating feel slow.
Do not skip the simple stuff
Most “running but not heating” checks start outside the heat pump: mode, setpoint, valves, controller, pump run time, water flow, and heat loss. These are easier to verify before assuming a major repair.
Step 1: Confirm the Heat Pump Is Actually in Heat Mode
This sounds obvious, but it is one of the first things to check. AquaCal’s manual says to confirm the heat pump mode is set to heat when troubleshooting a unit that is running but not heating.
On the five-button HP11 display, the Mode / Enter button is used to activate Heat Mode, Cool Mode, Auto Mode, or deactivate the equipment. In Heat Mode, the heat pump should be set up to warm the water toward the selected heat setpoint.
Check the display for:
- Heat Mode selected
- Heating light or heating status when calling for heat
- No active error code
- Thermostat setpoint higher than current water temperature
- Correct pool or spa body selected if groups are configured
If the unit is in Cool Mode, Auto Mode with the wrong setpoint, Off, or under external controller control, the behavior may not match what you expect.
Step 2: Set the Thermostat Above the Current Water Temperature
For heating, the thermostat needs to be set above the current water temperature. If the pool is 78°F and the heat setpoint is 78°F or lower, the heat pump may run briefly, maintain, or not heat aggressively because it has no reason to keep raising the temperature.
Setpoint 84°F
The heat pump has a clear heating target above the current water temperature.
Setpoint 76°F
The heat pump is not being asked to raise water temperature above where it already is.
For the fastest first heat-up, AquaCal recommends setting the desired heat setpoint and running the pool time clock at 24-hour operation until the desired temperature has been reached.
Step 3: Confirm the Valves Are Heating the Correct Body of Water
Valve position matters. AquaCal’s manual says to confirm the valves are positioned to heat the correct body of water, either the pool or spa. If heating a spa that overflows into a pool, the manual says to confirm the spa is isolated when being heated.
This is especially important on pool and spa combinations. If you are trying to heat the spa but the spa is spilling into the pool, the heat pump may be trying to warm a much larger body of water than expected. That can make it seem like the unit is not heating.
Pump moves water
Filter cleans water
Valves route water
Heat pump adds heat
Correct pool or spa warms
Pool/spa combo tip
If a spa is overflowing into the pool while you are trying to heat only the spa, the system may be losing heat into the larger pool volume. Isolate the spa when appropriate and follow your pool professional’s valve setup guidance.
For equipment-pad support, browse pool valves, check valves, pool fittings, and pool plumbing.
Step 4: Check Whether the Heat Pump Is Transferring Heat
AquaCal’s manual gives a practical way to confirm whether the heat pump is moving heat into the water: measure the temperature of the discharge air coming out of the heat pump fan. If the discharge air is 8°F to 16°F colder than the outside ambient air, the heat pump is moving heat into the water.
Outside air temperature
Use the outdoor air temperature near the equipment area as your comparison point.
Discharge air range
If discharge air is 8°F to 16°F colder than outside air, the unit is moving heat into the water.
Why the air gets colder
A heat pump pulls heat from the air and transfers it into the pool water. If the unit is heating properly, the air leaving the heat pump can feel cooler than the surrounding air.
If the discharge air test suggests the heat pump is transferring heat, but the pool is still not warming quickly, the issue may be heat loss, run time, water flow, pool size, cover use, or weather rather than a failed heat pump.
Step 5: Look for Error Codes Before Chasing Other Problems
If an error code is displayed, the manual says to diagnose and correct the cause of that code. Faults like No Water Flow, HIGH PRESSURE, LOW PRESSURE, HP5, LP5, defrost messages, or controller-related messages can change the troubleshooting path.
Before calling for help, record:
- The exact code or display message
- Whether the heat pump is in Heat Mode
- The current water temperature
- The heat setpoint
- Filter pressure reading
- Pump speed or RPM if using a variable-speed pump
- Photos of valve and bypass positions
- Photos of the full equipment pad
For related troubleshooting, see our AquaCal SuperQuiet guides on pressure fault codes, Delta-T water flow adjustment, and freeze protection.
Step 6: Confirm the Filter Pump Has Enough Run Time
The heat pump cannot heat the water without water flow. AquaCal’s manual specifically says to confirm that the filter pump has sufficient run time, because the heat pump will not run or heat the water without water flow.
For initial heat-up, AquaCal recommends setting the pool time clock to 24-hour operation, then resetting the circulation pump time clock to a normal time frame after the desired temperature has been reached.
Longer pump run time
Running the circulation system continuously during first heat-up gives the heat pump more time to raise the water temperature.
Limited heating window
If the pump only runs for a short schedule, the heat pump may not get enough operating hours to raise the pool temperature.
If you use a variable-speed pump, make sure the speed is high enough to provide proper flow through the heat pump. Browse pool pumps and variable-speed pumps if your circulation setup needs attention.
Step 7: Reduce Heat Loss From Water Features, Air Blowers and No Cover
Sometimes the heat pump is working, but heat loss is winning. AquaCal’s manual says that if heating a spa, deactivating the air blower or venturi can allow for quicker heating. For pools, it recommends deactivating water features such as slides, waterfalls, or fountains to help retain heat.
More air exposure
Water features increase exposure to air and can strip heat from the water, especially in cool or windy conditions.
Heat escapes fast
Air blowers and venturi air can make spa heating feel slower by increasing heat loss.
Heat leaves overnight
A pool blanket or liquid blanket can help retain heat and support quicker heating times.
Simple heating-speed trick
During first heat-up, turn off waterfalls, fountains, slides, spillovers, and unnecessary air features when possible. Use a pool cover or liquid blanket to reduce heat loss.
To help retain heat, browse pool covers, solar covers, and cover reels.
Running But Not Heating vs Heating Slowly
There is a difference between a heat pump that is not heating at all and a heat pump that is heating slowly. This distinction matters because a slow temperature rise may be normal during first heat-up, especially with a large pool, cool air, wind, no cover, limited pump run time, or heavy heat loss.
| Situation | What It Usually Means | What to Check |
|---|---|---|
| Unit running, discharge air colder | The heat pump may be transferring heat into the water. | Run time, cover use, heat loss, pool size, valve position, weather, and expectations. |
| Unit running, no temperature change at all | The heat may not be reaching the correct body of water, or there may be a setup or service issue. | Mode, setpoint, valves, external controller, water flow, and error codes. |
| Unit starts and stops with codes | The heat pump may be protecting itself due to a detected issue. | Displayed fault code, water flow, filter pressure, pump speed, airflow, and service support. |
| Spa heating but not getting hot quickly | Heat loss or spillover may be slowing recovery. | Isolate spa, shut off blower or venturi, stop spillover if appropriate, and confirm setpoint. |
External Controllers Can Make Troubleshooting Confusing
If your AquaCal SuperQuiet is tied into an external controller, automation system, remote relay, or multiple heat pump setup, the heat pump may not behave like a standalone unit. The manual says that if the heat pump is using an external controller, confirm that the controller is set correctly.
In some cases, the heat pump may be set to accept signals from the controller, while the controller is not actually calling for heat. In other cases, the heat pump may work manually but not through automation because of configuration issues.
External controller checks:
- Confirm the controller is calling for heat.
- Confirm the controller is set to the correct pool or spa body.
- Confirm the controller’s heating setpoint is above current water temperature.
- Confirm the heat pump is configured to accept the controller signal.
- Check the controller manual if the heat pump works manually but not through automation.
If you are unsure whether the issue is the AquaCal unit or the automation system, take photos of the display, controller screen, and equipment pad before asking for support.
Water Flow Still Matters Even When the Unit Is Running
A heat pump can only heat water that is moving through it correctly. If water flow is too low, being bypassed, restricted by a dirty filter, or disrupted by valve settings, the unit may underperform or show error codes.
AquaCal lists SQ140R and SQ200R heat pump flow rates at 30 to 70 GPM. It also warns that dirty filters, debris-filled baskets, and improper valve settings can reduce water flow to the heat pump.
Required heat pump flow
The SQ140R needs proper water flow through the heat pump to perform correctly.
Required heat pump flow
The SQ200R also needs 30 to 70 GPM through the heat pump.
For flow-related maintenance, browse pool filter cartridges, filter parts, pool cleaning products, and pool valves.
What to Send Aqua Terra Backyard if You Need Help
If you purchased your AquaCal heat pump through Aqua Terra Backyard and need help figuring out why it is running but not heating, send clear information up front. That gives us a better chance to point you in the right direction.
Send us:
- Your order number
- Heat pump model and serial number
- Current pool or spa water temperature
- Current heat setpoint
- Photo of the AquaCal display
- Any active error code or message
- Photo of the full equipment pad
- Photos of valve and bypass positions
- Filter pressure reading
- Pump speed or schedule if using a variable-speed pump
- Whether waterfalls, fountains, spa spillovers, blowers, or air features are running
- Whether you are using a pool cover or liquid blanket
You can review our Warranty Procedure page or contact Aqua Terra Backyard with your equipment details and photos.
When to Call a Qualified Technician
Call for service if the unit is in Heat Mode, the setpoint is correct, valves are positioned properly, water flow appears correct, pump run time is sufficient, heat loss has been reduced, and the heat pump still does not appear to transfer heat into the water.
- The unit shows repeated fault codes.
- The fan or compressor does not appear to operate correctly.
- The discharge air test does not suggest heat transfer.
- The unit starts and stops repeatedly.
- There is ice buildup that does not clear properly.
- The heat pump is controlled by automation and settings are unclear.
- The issue involves electrical, refrigerant, sensor, or internal component diagnosis.
Do not open the cabinet and guess
Internal heat pump service should be handled by qualified professionals. Refrigerant, compressor, fan motor, electrical, sensor, and control-board diagnosis are not homeowner repair items.
Which AquaCal SuperQuiet Models Does This Apply To?
This guide is written for AquaCal HeatWave SuperQuiet owners and shoppers using the HP11 five-button display style manual, especially the SQ140R and SQ200R models Aqua Terra Backyard carries.
AquaCal HeatWave SuperQuiet SQ140R
A strong residential heat pump option for efficient pool heating with quieter operation and modern AquaCal performance.
AquaCal HeatWave SuperQuiet SQ200R
A higher-capacity AquaCal SuperQuiet model for larger pools or stronger heating demand.
You can also browse the full AquaCal Heat Pumps collection to compare current AquaCal heat pump options.
Get the Heat Into the Water, Then Keep It There
If your AquaCal SuperQuiet is running but not heating, work through the basics before assuming failure: Heat Mode, thermostat setpoint, valve position, external controller setup, error codes, pump run time, water flow, and heat loss. In many cases, the heat pump is running but the system around it is not helping it heat efficiently.
Aqua Terra Backyard carries AquaCal heat pumps, pool covers, valves, plumbing parts, pumps, filter products, and pool equipment to help homeowners build better-performing backyard systems.
FAQs About AquaCal SuperQuiet Running But Not Heating
Why is my AquaCal SuperQuiet running but not heating?
Common causes include the wrong mode, setpoint too low, incorrect valve position, external controller issue, insufficient filter pump run time, poor water flow, active error code, or heat loss from water features, spa air, wind, or no cover.
What mode should my AquaCal be in to heat the pool?
The heat pump should be in Heat Mode when the goal is to raise water temperature. The thermostat should also be set above the current water temperature.
How can I tell if my AquaCal heat pump is transferring heat?
Measure the air discharge coming out of the fan. AquaCal says if the discharge air is 8°F to 16°F colder than the outside ambient air, the heat pump is moving heat into the water.
Does the filter pump need to run for the heat pump to heat?
Yes. The heat pump will not heat without water flow. During initial heat-up, AquaCal recommends setting the pool time clock to 24-hour operation until the desired temperature is reached.
Can waterfalls or fountains make my pool heat slower?
Yes. AquaCal recommends deactivating water features like slides, waterfalls, or fountains to help retain heat. These features increase heat loss, especially in cooler weather.
Can a spa blower slow heating?
Yes. If heating a spa, AquaCal recommends deactivating the air blower or venturi, if equipped, to allow for quicker heating times.
Should I use a pool cover with an AquaCal heat pump?
Yes, a pool blanket or liquid blanket can help retain heat and support quicker heating times, especially during first heat-up or cool nights.
What flow rate does the AquaCal SQ140R or SQ200R need?
Both the SQ140R and SQ200R require 30 to 70 GPM through the heat pump. Poor flow can reduce performance or trigger faults.
Can an external controller stop my AquaCal from heating?
Yes. If the heat pump is controlled by automation or an external controller, confirm the controller is set correctly and actually calling for heat.
Where can I buy AquaCal SuperQuiet heat pumps?
You can shop the AquaCal HeatWave SuperQuiet SQ140R, AquaCal HeatWave SuperQuiet SQ200R, and other AquaCal heat pumps at Aqua Terra Backyard.
Final Takeaway: The Unit May Be Running Correctly, But the System Still Needs Help
When an AquaCal SuperQuiet heat pump is running but not heating, the issue is often not as simple as “working” or “broken.” The unit may be running, but the pool may not be retaining heat, the thermostat may not be calling correctly, the valves may be sending water to the wrong place, the controller may be misconfigured, or the pump may not be running long enough.
Start with the safe checks: Heat Mode, setpoint, valve position, controller setup, error codes, pump run time, water flow, discharge air temperature, and heat loss. If the heat pump still does not appear to transfer heat, get a qualified technician involved.
Need help choosing an AquaCal heat pump or related pool equipment? Browse AquaCal Heat Pumps, or contact Aqua Terra Backyard with your pool size, current equipment, model number, photos, and heating questions.