17 November 2025
Complete Guide to Fixing F1 Errors in Your MSpa Portable Spa
If you've experienced an F1 error with your MSpa portable spa, you're not alone. The F1 error is one of the most common technical issues spa owners encounter, but don't worry — it's also one of the easiest to resolve with some simple troubleshooting and regular maintenance. In this guide, we'll walk you through everything you need to know about F1 errors, including what they are, why they happen, and how to resolve them so you can get back to enjoying your spa.
Before you do anything else: check the pump is actually running
Most F1 errors are a simple flow problem you can fix in a few minutes. But sometimes an F1 is your spa telling you the pump itself has stopped, and if that's the case, cleaning filters or draining the pool won't fix it. So before you change anything, run this quick check:
- Turn the spa off and lift out the filter cartridge. Clear any debris from the inlet and outlet grills.
- Turn the power back on and press reset on the PRCD (the test button on the power cord).
- Press the filter button. Listen for the pump, and hold your hand near the outlet grill to feel for water moving.
If you can hear the pump and feel water flowing, the pump is fine. Work through the steps below.
If you can't hear the pump and there's no water at the outlet, the pump has likely failed. Don't drain and refill the spa, you'll tip out around a thousand litres for nothing. Get in touch and we'll sort the next step with you.
Read the full walkthrough →
In a hurry? If the pump is running, the most common F1 cause is a dirty or aged filter cartridge. Skip ahead to Step 1: Clean or Replace the Filter.
What is an F1 Error?
The F1 error is a flow error that occurs when the control unit in your spa detects a blockage or reduced water flow through the system. It's a protective mechanism designed to prevent severe internal damage to the control unit. When this error appears, the spa's heating and filtering functions will stop until the issue is resolved.
What Causes an F1 Error?
An F1 error is typically triggered by one of the following:
- ⚠Dirty or Clogged Filters: Filters must be cleaned weekly and replaced every 4–6 weeks. Over time, debris, oils, and residue clog the filter, restricting water flow.
- ⚠Debris in the Filter Grills: Debris such as lint, hair, or small particles can accumulate in the filter inlet or outlet grills, causing reduced flow.
- ⚠Water Level Issues: Insufficient water in the spa can cause air to enter the system, triggering the F1 error.
- ⚠Airlocks: After refilling your spa, air bubbles can get trapped in the system, causing it to fail to detect proper water flow.
How to Fix an F1 Error
Follow these steps to resolve an F1 error and get your spa back in action:
1Clean or Replace the Filter
- Turn off the spa before removing the filter to prevent debris from being sucked into the system.
- Unscrew the filter from the inlet grill and rinse it thoroughly with a garden hose. If the filter appears brown or damaged, replace it immediately. It is advisable to replace filters every 4–6 weeks.
❖Quick check
If your filter is more than 3 months old, or looks grey, slimy, or stained, cleaning probably won't restore full flow.
View compatible replacement cartridges →2Clear the Inlet and Outlet Grills
- Remove the filter cartridge base if your spa has one.
- Gently clean around the inlet and outlet grills using your hand or a small brush. For deeper cleaning, you may need to remove the grills entirely, but ensure the water level is below the grills before doing so to avoid water entering the control unit.
- Use a garden hose to flush the grills thoroughly.
3Check the Water Level
- Ensure the water level in the spa is at or above the "MIN" line.
- If it's low, top it up to the proper level and test the system again.
4Resolve Airlocks
- Airlocks often happen after refilling the spa. To fix this:
- Turn off the spa.
- Locate the grey threaded collar on the pipe connection between the spa and the control unit.
- Loosen the collar slightly to release trapped air until water trickles out, then tighten it again.
5Power Cycle the Control Unit
- Turn the spa off completely at the wall or by pressing the test button on the power cord.
- Wait a few minutes, then turn the spa back on and check if the error clears.
Preventing Future F1 Errors
Prevention is always better than cure. Follow these tips to keep your spa running smoothly:
Regular Filter Maintenance
- Clean your filter weekly.
- Replace filters every 4–6 weeks to ensure consistent water flow.
Keep the Water Balanced
- Test and balance your water weekly using the Portable Spas Water Testing App.
- Maintain pH levels between 7.2 and 7.8 to prevent limescale or debris buildup that could restrict water flow.
Monitor Water Levels
- Always keep the water level above the minimum line. Avoid excessive splashing, which may cause air to enter the system.
Inspect the System Regularly
- Check the inlet and outlet grills for blockages and clean them as necessary.
- If your spa is left unused for extended periods, drain and clean the system to prevent debris buildup.
Keep Your Spa Running Smoothly
A fresh filter and balanced water are the two best ways to avoid F1 errors altogether. Stock up on replacement cartridges, sanitiser, and pH balancers in one place — everything compatible with your MSpa.
Shop Filters & Chemicals →When to Contact Portable Spas New Zealand
If the F1 error persists despite following the steps above, your control unit may need professional attention. You can send it to our technical team in Christchurch for assessment. Please package the control unit carefully (a banana box works great!) and include the return control unit form.
For further assistance, reach out to us at service@portablespas.co.nz.
Conclusion
Experiencing an F1 error with your MSpa portable spa doesn't have to be a stressful situation. By understanding the causes and following these simple troubleshooting steps, you can clear the error and take steps to prevent future occurrences. Remember, proper filter maintenance, water care, and system inspections are key to a trouble-free spa experience.
Have more questions about spa maintenance? Check out our water care guide or contact our friendly team at Portable Spas New Zealand for support.