Operation, Winterising & Troubleshooting Guide
Everything you need to know about running, maintaining, and troubleshooting your inverter pool heat pump. Heat to 40°C, chill to 8°C, year-round swimming from ~$500 per year.
How an Inverter Heat Pump Works
An inverter pool heat pump works like a reverse air conditioner. It captures warmth from the ambient air and transfers it to your pool water through a refrigeration cycle. A fan draws air across an evaporator coil containing refrigerant. The refrigerant absorbs heat, is compressed by a Mitsubishi inverter compressor to increase its temperature, then passes through a titanium heat exchanger where it transfers the heat to your pool water.
What makes inverter technology different: Unlike older on/off heat pumps, an inverter compressor modulates its speed to match the heating demand. Instead of cycling on and off at full power, it runs continuously at the exact speed needed. This is why running costs are so low — approximately $500 per year for extended season swimming, up to 80% less than gas heating.
The Paradise range uses R32 refrigerant rated for operation down to -15°C ambient air temperature, with a UV-resistant casing and anti-corrosion titanium heat exchanger built for Australian conditions. It works with chlorine, saltwater, mineral, and magnesium pools with no additional equipment needed.
Startup procedure:
- Ensure the pump is running and water is flowing through the system
- Turn on the heat pump at the mains power supply and isolator switch
- Set your desired pool temperature on the LCD touchscreen or WiFi app
- The fan will start spinning and the unit will begin heating
- Allow 24 to 48 hours for the pool to reach target temperature from cold
Best practices for lowest running costs:
- Run the pump during the warmest part of the day for maximum efficiency (typically 10am to 6pm)
- Use a pool cover when the pool is not in use. Up to 80% of heat loss is through evaporation
- Set the temperature and leave it. The inverter modulates output to maintain it efficiently
- Use the WiFi app to schedule heating so the pool is ready when you want it
- Condensation water dripping from the unit is normal — this is from the evaporator coil
How to use chill mode:
- On the LCD touchscreen or WiFi app, select Cool/Chill mode
- Set your target temperature (as low as 8°C)
- The unit will reverse the refrigeration cycle to extract heat from the pool water
- The fan will exhaust warm air as it cools the water
Cold plunge benefits:
- Faster muscle recovery. Cold water immersion reduces post-exercise inflammation. 10 minutes at 12 to 15°C is enough for measurable results
- Better circulation. The cold-warm contrast causes blood vessels to expand and contract, improving cardiovascular efficiency
- Mental clarity. A short cold immersion triggers a noradrenaline release for focus and mood improvement
- Summer refresh. On a 40°C day, chilling your pool to 22°C makes it more refreshing than swimming in bath-warm water
Winterising steps (if not using through winter):
- Turn off power to the heat pump at the mains and at the unit isolator switch
- Isolate water flow. Close the inlet and outlet valves to the heat pump
- Drain the heat exchanger. Remove the drain plug(s) and allow all water to drain completely. Water left inside can freeze and crack the titanium heat exchanger
- Loosen barrel unions to break the seal and allow any remaining water to escape
- Cover the unit with a breathable cover. Do not use plastic sheeting which traps moisture
- Leave drain plugs out and valves closed until recommissioning
| Check | What to look for | Solution |
|---|---|---|
| Set temperature | Set lower than or equal to current water temp | Check your set point is higher than the current pool temperature. The unit will not heat if already at or above the target. |
| Operating mode | Unit in Cool mode instead of Heat | Check the mode setting on the display or app. Switch to Heat mode. |
| Air temperature | Below effective operating range | Paradise units are rated to -15°C, but efficiency drops in very cold air. Heating will be slower. The unit should still produce heat. |
| Water flow | Insufficient flow through heat exchanger | Clean skimmer and pump baskets. Backwash or clean filter. Check for closed valves. Check pump is running at adequate speed. |
| Evaporator coil | Dirty, blocked, or iced up | Clean the coil fins gently with a soft brush or low-pressure hose (turn power off first). Ensure at least 600mm clearance around the unit for airflow. |
| Run time | Not running long enough | Heat pumps heat gradually (1 to 2 degrees per day). A cold pool may take 2 to 3 days to reach temperature. Run the pump 10 to 12 hours daily during heat up. |
| Pool cover | Not using a cover overnight | Without a cover, overnight heat loss can equal or exceed the day's heat gain. The pool may never reach target temperature. A cover is essential. |
- Check mains power. Confirm the circuit breaker has not tripped. Reset if necessary. If it trips again immediately, there may be an electrical fault requiring a licensed electrician.
- Check isolator switch. Heat pumps have a dedicated isolator switch near the unit. Ensure it is in the ON position.
- Check pump is running. Heat pumps require water flow to operate. If the pool pump is off, the heat pump will not start. The flow sensor must detect adequate water movement.
- Check timer settings. If connected to a timer or automation system, confirm the timer is in the ON period.
- Check the display for error codes. Refer to your manual. Common codes indicate flow issues, temperature sensor faults, or communication errors.
- Check WiFi module. If controlling via the app, ensure the WiFi module is connected and the unit is within range of your home network.
- Check pump is running at adequate speed. Variable speed pumps set too low will not provide enough flow for the heat pump
- Clean skimmer and pump baskets. Blockages restrict water flow
- Backwash or clean your filter. A dirty filter is the most common cause of flow errors
- Check all valves. Ensure inlet and outlet valves to the heat pump are fully open
- Check for air in the system. Air locks can prevent water flow. Prime the pump and bleed air from the filter
- Inspect the flow sensor (if accessible) for debris or damage
| Situation | Is it normal? | What to do |
|---|---|---|
| Light frost on coil in cold weather | ✅ Normal | The defrost cycle will clear it automatically. No action needed. |
| Ice on lower portion only, unit still heating | ⚠️ Monitor | Check the defrost cycle is functioning. If ice persists for more than 1 hour, there may be a defrost sensor or refrigerant issue requiring a technician. |
| Thick ice covering entire coil, unit not heating | ❌ Not normal | Turn the unit off. Possible causes: low refrigerant, faulty defrost sensor, blocked airflow, or dirty coil. Requires a licensed refrigeration technician. |
| Ice on one section only | ❌ Not normal | Likely indicates low refrigerant or a restriction in the refrigeration system. Requires a licensed technician. |
| Noise | Likely cause | What to do |
|---|---|---|
| Rattling or vibrating | Loose panels, debris in fan, unit not level | Check for loose screws or panels. Remove debris from fan area. Ensure unit is on a level, stable base. |
| Grinding or squealing | Fan motor bearing failing | Turn unit off. Requires fan motor inspection or replacement by a technician. |
| Loud buzzing or humming | Compressor struggling, electrical issue | Check for error codes. May indicate a failing capacitor, contactor, or compressor. Requires a technician. |
| Gurgling or bubbling | Air in the water heat exchanger | Check for air leaks in the plumbing. Bleed air from the filter. Ensure pump is fully primed. |
| Clicking on and off frequently | Short cycling due to flow or temperature issues | Check water flow. Check set temperature. Short cycling damages the compressor. Address promptly. |
App features:
- Remote temperature control. Adjust your pool temperature from anywhere
- Smart scheduling. Set the heat pump to run at specific times. Schedule it to hit 28°C by 5pm on weekdays
- Mode switching. Toggle between Heat and Cool modes instantly
- Performance monitoring. Check current water temperature, set point, and operating status
- Error notifications. Receive alerts if the unit detects a fault
App troubleshooting:
- Ensure the heat pump is within WiFi range of your home network
- The WiFi module is included in the box and connects during installation
- If the app cannot connect, power cycle the heat pump and check your home WiFi is working
- Refer to the manual for specific app setup instructions for your model
✅ Inverter Heat Pump
Heats to 40°C and chills to 8°C. Runs on ~$500/yr — up to 80% less than gas. WiFi app control, 40dB quiet operation. Works in any weather including overcast and cool nights. Takes 24 to 48 hours to heat from cold. Best overall value for regular pool users.
⚠️ Gas Heater
Heats faster than any other method. Unaffected by ambient air temperature. Cannot chill — heating only. Running costs ~$2,500/yr — 5x more than a heat pump. Best suited to occasional or short-burst heating rather than regular swimming. Not our primary focus for support.
⚠️ Electric Resistance
Lower purchase price. Compact — good for spas and very small pools. Cannot chill — heating only. Running costs ~$4,000/yr — the most expensive heating method. Struggles to heat larger pools effectively. Not our primary focus for support.
🔌 Always turn off mains power and the isolator switch before inspecting, cleaning, or servicing the heat pump.
💧 Drain the heat exchanger completely if winterising in frost-prone areas. Frozen water expands and cracks titanium. This damage is not covered by warranty.
🌬️ Maintain clearance. Keep at least 600mm of clear space around the unit for proper airflow. Trim vegetation, remove leaves and debris regularly.
🧹 Clean the evaporator coil every 3 to 6 months. Turn off power, then gently clean with a soft brush or low-pressure hose. A dirty coil reduces efficiency and increases running costs.
🔧 Annual service recommended. Have a licensed refrigeration technician check refrigerant levels, electrical connections, and overall operation annually.
📱 Keep the app updated. Firmware and app updates improve performance and add features. Check for updates periodically.
| Problem | Most likely cause | Check |
|---|---|---|
| Not heating | Set point, mode, or water flow | Check settings and flow |
| Won't turn on | Power, isolator, or pump not running | Check power and pump |
| Flow error | Dirty filter or closed valve | Clean filter, check valves |
| Icing up | Defrost cycle or airflow issue | Check defrost and clearance |
| Unusual noise | Debris, loose panels, or bearing | Inspect and clean unit |
| App not connecting | WiFi range or module issue | Check WiFi and power cycle |
| Pool losing heat overnight | No pool cover | Use a cover. 80% of heat loss is evaporation |
| High running costs | No cover, wrong settings, or dirty coil | Use cover, schedule smartly, clean coil |
🔥 Heat Pump FAQs
Approximately $500 per year for extended season swimming (September to May). This varies by pool size, location, usage, and whether you use a pool cover. Compared to gas heating (~$2,500/yr) and electric resistance (~$4,000/yr), an inverter heat pump is the most affordable way to heat a pool. The unit typically pays for itself vs gas in about 18 months.
Yes. The Paradise range heats to 40°C and chills to 8°C. It's the only pool appliance that does both. In summer you can chill the pool for cold plunge therapy or simply cool it to a refreshing temperature on hot days. Toggle between heat and chill from the LCD screen or WiFi app.
Approximately 1 to 2 degrees per day for an average pool. A cold pool may take 2 to 3 days to reach swimming temperature initially. Once at temperature, the inverter modulates to maintain it efficiently. Using a pool cover significantly reduces heat up time and running costs.
Yes. Up to 80% of heat loss from a pool occurs through evaporation. Without a cover, overnight heat loss can equal or exceed the day's heat gain, meaning the pool may never reach or maintain temperature. A cover is the single most effective way to reduce heating costs and heat up time.
The Paradise range runs at approximately 40dB in normal operation. This is quieter than a library (40dB), a quiet conversation (50dB), and significantly quieter than older heat pump technology or air conditioner outdoor units. You will not know it is running from inside the house, and neither will your neighbours.
The titanium heat exchanger is compatible with chlorine, saltwater, mineral, and magnesium pools. No additional equipment or chemical adjustments are needed. The anti-corrosion titanium construction is designed specifically for Australian pool chemistry conditions.
The unit arrives fully assembled. A licensed electrician must connect the power. The water lines can be handled by a plumber or a confident DIYer. Typical installation costs are $300 to $600 for plumbing plus electrical connection. For larger models (21kW and above), we recommend an electrical line check before purchasing.
📱 1300 511 901 | ✉️ support@mrpoolman.com.au
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🔥 Ready for year-round swimming from ~$500/yr?
Shop the Paradise inverter heat pump range. Heat to 40°C, chill to 8°C, WiFi app control, whisper-quiet 40dB operation.
© Mr Pool Man — Inverter pool heat pump operation, winterising and troubleshooting guide. Always consult your specific unit's manual for model-specific instructions.