Modern heating systems are designed to make your life easier, and that includes your air source heat pump. But, when something goes wrong here, sorting it out isn’t exactly easy. It’s not going to just tell you what the problem is.
Instead, it’ll come out with various heat pump fault codes. The good news is these are warning signs rather than an immediate danger. But, it means you’ll have to take action relatively quickly.
That’s why knowing what these fault codes mean, and what to do about them, matters.
Why Heat Pump Fault Codes Matter
Fault codes are your system’s way of saying something isn’t right. Ignoring them can lead to more than a few issues as time goes on. Some of the more common of these are:
- Reduced efficiency.
- Higher energy bills.
- Bigger (and more expensive) problems.
- A shortened system lifespan.
Regular air source heat pump servicing helps to find, diagnose, and fix these issues before they escalate. This keeps your system running smoothly and efficiently year-round.
That’s why it’s always worth knowing what the most common heat pump fault codes are, and what you should do about them. Ten of these are some of the more common, and you could run into a few of them, depending on your system and how you use it.
Heat Pump Fault Codes: 10 Common Codes & What They Mean
1. E1/F1 – Low Refrigerant
This is one of the most common codes in an air source heat pump and is related to the refrigerant. It means your system doesn’t have enough refrigerant to transfer heat effectively, usually because of some kind of leak.
Reduced heating performance, ice forming on the outdoor unit, and the system running constantly are some of the more notable signs to look out for. This isn’t a DIY fix, though. You’ll need air source heat pump servicing to find and fix the leak, and recharge the system.
2. E2 – High Pressure Fault
This means the pressure inside of your system is too high, often because of restricted airflow or dirty components. The common causes for this are blocked filters, dirty coils, and poor ventilation.
To fix this, turn the system off and check for obvious blockages. Then book a heat pump servicing to prevent long-term damage.
3. E3 – Low Pressure Fault
This is a code for a low pressure fault, which can often be linked to refrigerant issues or leaks. While this mightn’t seem like an issue, it can be. Running the system with low pressure damages internal components in time.
This is another issue best left to a professional. Call a qualified engineer to have your heat pump serviced and fixed.
4. DF – Defrost Fault
This heat pump fault code means there’s a defrost fault, which often happens because your heat pump is struggling to operate efficiently in cold conditions. The more obvious signs of this are when ice builds up on the outdoor unit and there’s a reduced heating output.
While occasional frost is normal, persistent frost indicates a fault. Regular air source heat pump servicing makes sure the defrost cycle works properly.
5. F3/E4 – Fan Motor Fault
These are fan motor faults that mean the fan in the outdoor unit isn’t working the way it should be. There are a few possible causes for this, with the most common (and obvious) being motor failure, electrical issues, and debris blocking the fan.
Switch off the system when you get these heat pump fault codes and arrange for your system to be serviced. Running the pump like this runs the risk of overheating, which causes more damage.
6. E5 – Sensor Fault
An E5 fault means that a temperature or pressure sensor isn’t reading correctly. These systems help regulate your system. So, if they fail, performance drops and efficiency suffers. A technician will usually need to fix this for you. That normally involves testing the sensors and replacing the faulty ones during servicing.
7. E6 – Communication Error
An E6 error means the indoor and outdoor units aren’t communicating with each other the way they should be, if they’re communicating at all. The common causes for this are wiring faults, loose connections, and circuit board issues.
This needs a professional diagnosis, especially when it comes to keeping your system running safely and efficiently. Book an air source heat pump servicing to have this addressed properly.
8. E7 – Compressor Fault
This means there’s an issue with your compressor, which is the heart of your heat pump. The compressor is often one of the most expensive parts in your system to repair or replace. Call an engineer as soon as you get this heat pump fault code to prevent further compressor strain and, possibly, failure.
9. E8 – Water Flow Fault
The E8 fault code means there’s not enough water flowing through your system. The possible causes for this are airlocks, blocked pipes, and pump failure. There could even be a mix of these. Check the system pressure if it’s safe to do so, and then have a heat pump servicing professional come in to fix the issue.
10. E9 – Power Supply Fault
An E9 code means your heat pump isn’t getting a stable power supply so it can operate. Electrical faults, voltage fluctuations, and loose connections are some of the more common causes of this. Check your fuse box for obvious issues, but leave a deeper diagnosis to professionals.
Get a Professional in for Your Heat Pump Fault Codes
Heat pump fault codes look confusing, but they can actually be a helpful feature of your air source heat pump. They give you warning signs before small issues become large problems. You’ll need to pay attention to them and take action relatively quickly.
Thankfully, they don’t have to be too hard to understand. At least, that’s the case when it comes to the more common ones you’ll come across. And, with an air source heat pump servicing, dealing with them doesn’t have to be as hard as you’d think.
