Is your Sime boiler displaying an fault code? Do you want to know what it means? We’ve got the answer for you in this blog!
Is your Sime boiler displaying an fault code? Do you want to know what it means? We’ve got the answer for you in this blog!
When a boiler experience issues, it will turn off or, as we call it in the heating world, ‘lockout’ to protect itself and prevent potential damage.
Your Sime boiler will then display an error code to give you (and the heating engineer) information on what the problem could be.
In this blog, we’ve listed every Sime boiler error code/ fault code you may encounter to help you understand the issues and roughly estimate how much it will cost you to fix them.
But first, remember that you should always follow the boiler manual instructions and even if you know what the fault code means, make sure that a Gas Safe Registered engineer carries out the repairs.
Before you read this blog, remember that if your boiler is on its last legs, it might be easier and cheaper to replace it rather than fork out repairing it. So check out our boiler comparison tool; it allows you to compare up to three boiler brands and models at once to help you find the best boiler for your home!
About Sime Boilers
Sime, the “Italian Stallion”, offers innovative domestic and commercial heating solutions designed and manufactured in Italy, tailored to the British climate and conditions, providing the most advanced and efficient heating and hot water solutions.
With a proven reputation for reliability, durability and performance, Sime domestic and commercial boilers combine the stylish design and innovative engineering synonymous with their Italian heritage.
Common Sime boiler problems
Low pressure
Low pressure is a common boiler issue and this is often the cause of a boiler not working. The pressure gauge will tell you if the pressure is low and if it is, it’s easily fixable.
Your manual will be able to give you step-by-step instructions on how to top up the pressure. Most boilers will automatically reset and the error code will disappear once you have done this.
Air in the system
Air in your system can cause your radiators to stop working. If you turn your heating on for the first time in months and find that your radiators aren’t getting hot, then this could mean that your radiators need bleeding. Bleeding your radiator is simple – all you need to do is remove the valve on the side of your radiator to let out the trapped air. Make sure the heating is off when you do this. You may also want to have a bowl ready in case any water escapes.
Remember, bleeding your radiators can also lead to low pressure. Be sure to check the pressure in your system once you have bled them.
Frozen condensate pipe
One of the most common problems with your boiler during cold weather is a frozen condensate pipe. While a qualified heating engineer is usually the first port of call, you will be left without using your boiler and will have to pay costly call-out fees.
Luckily, you can do this job yourself with a bit of guidance, and we’re here to walk you through it step-by-step, so put down your wallet!
If your pipe is frozen and easy to access, you can defrost it yourself using warm water (yes, it’s that simple!). Just read our blog to find out how to unfreeze your condensate pipe safely.
Fault Codes/Error codes
If your boiler has stopped working, it’ll usually display a boiler fault code. This code will help you identify the cause of the problem and give you (and the heating engineer) an idea of how to fix it!
For example, if you run out of gas on your pre-paid meter, your boiler will display a fault code. Once the gas supply has been reinstated, you’ll have to reset your boiler. Nonetheless, if you are still unsure about what to do, an installer would be able to give you advice over the phone, or you can contact Sime directly on 0345 901 1114.
Below, you’ll find some of the most common Sime boiler error codes/ fault codes to help you identify the issue with your boiler.
Sime Boiler Error Codes
Fault code | Description |
| AL02 | Low water pressure in the system |
How to solve AL 02 Sime error code?
Restore pressure
If your boiler pressure is low, you’ll see the bars on the pressure gauge going down (below the standard pressure).
In this case, we advise referring back to the boiler manual to learn how to re-pressurise your boiler; the manual includes step by step instructions to help you.
Once you’ve re-pressurised your boiler, it’s time to give it a quick reset. Most boilers will automatically reset, and the error code will disappear once you have done this.
Check for any leaks in the system
If you have attempted to repressurise your boiler already and still notice a drop in your boiler pressure, then you will need to get advice from a Gas Safe Engineer and ask them to come and check for leaks. If you have a leak then it will usually require them to reseal or potentially re-pipe your system where necessary.
Fault code | Description |
| AL03 | High water pressure in the system |
How to solve AL 03 Sime error code?
This is a job for the heating engineer, they’ll empty the system via the drain valve on the Hydraulic assembly to bring the pressure to approximately 1.2 bar.
Fault code | Description |
| AL04 | Domestic hot water sensor (SS) fault |
How to solve AL 04 Sime error code?
To solve this problem the heating engineer will check connections and replace the sensor.
Fault code | Description |
| AL05 | Delivery sensor (SM) fault |
How to solve AL 05 Sime error code?
The heating engineer will check connections and replace the sensor to solve this issue.
Fault code | Description |
| AL06 | No flame detection |
How to solve AL 06 Sime error code?
The heating engineer will perform the following;
- Check the integrity of the electrode and
- Check that it is not grounded
- Check gas availability and pressure
- Check the operation of the gas valve
Fault code | Description |
| AL07 | Safety thermostat (TS) intervention |
How to solve AL 07 Sime error code?
Another job for the heating engineer-
- Check the sensor or thermostat connections
- Deaerate the system
- Check the bleed valve
- Replace the sensor or the thermostat
- Check that the pump impeller is not blocked
Fault code | Description |
| AL08 | Fault in the flame detection circuit |
How to solve AL 08 Sime error code?
The heating engineer will;
Check the integrity of the electrode and check that it is not grounded
- Check gas availability and pressure
- Check the operation of the gas valve
Fault code | Description |
| AL09 | No water circulating in the system |
How to solve AL 09 Sime error code?
You must call the heating engineer to;
- Check the rotation of the system pump impeller
- Check the electrical connections
- Replace the pump (if needed)
Fault code | Description |
| AL10 | Auxiliary sensor fault |
How to solve AL 10 Sime error code?
- Check the hydraulic configuration in the boiler
- Check the electrical connection
Fault code | Description |
| AL11 | Auxiliary sensor fault |
How to solve AL 11 Sime error code?
Check the electrical connection
Fault code | Description |
| AL12 | Incorrect configuration of the open/sealed chamber |
How to solve AL 12 Sime error code?
Set the parameter tS 0.4 (Combustion configuration) to 0
Fault code | Description |
| AL13 | Exhaust sensor (SF) intervention |
How to solve AL 13 Sime error code?
- Replace the smoke probe
- Contact the Technical Assistance Centre
Fault code | Description |
| AL14 | Exhaust sensor (SF) fault |
How to solve AL 14 Sime error code?
- Replace the smoke probe
- Check the electrical connection of the smoke probe, if the problem is not resolved, contact the Assistance Centre
Fault code | Description |
| AL15 | Fan check cable disconnected |
How to solve AL 15 Sime error code?
Check the connection cable between the fan and the board
Fault code | Description |
| AL18 | Condensate level fault |
How to solve AL 18 Sime error code?
- Check for any clogging in the pipe which takes the condensate to the siphon
- Check that the siphon is not clogged
Fault code | Description |
| AL28 | Maximum number of consecutive resets reached (6) |
How to solve AL 28 Sime error code?
- Contact the Technical Assistance Centre AL 37 Fault due to low network voltage.
- Check with tester
- Contact network provider (ENEL)
Fault code | Description |
| AL40 | Incorrect supply frequency detected |
How to solve AL 40 Sime error code?
Contact network provider (ENEL)
Fault code | Description |
| AL41 | Flame loss more than 6 consecutive times |
How to solve AL 41 Sime error code?
- Check the detection electrode
- Check the gas supply (open valve)
- Check mains gas pressure
Fault code | Description |
| AL42 | Button fault |
How to solve AL 42 Sime error code?
Check that buttons are working
Fault code | Description |
| AL43 | Open Therm communication fault |
How to solve AL 43 Sime error code?
Check the electrical connection of the remote control
Fault code | Description |
| AL62 | Self-calibrating procedure is required |
How to solve AL 62 Sime error code?
Carry out the self-calibrating procedure
Fault code | Description |
| AL72 | Incorrect positioning of the delivery sensor |
How to solve AL 72 Sime error code?
Check that the delivery sensor is attached to the delivery pipe
Fault code | Description |
| AL81 | Block due to combustion during start-up |
How to solve AL 81 Sime error code?
- Check for blockage in flue
- Bleed the air from the gas circuit
Fault code | Description |
| AL83 | Block due to combustion during start-up |
How to solve AL 83 Sime error code?
Check for blockage in the flue
Fault code | Description |
| AL96 | Lockout due to flue (exhaust) blockage |
How to solve AL 96 Sime error code?
Check for blockage in flue
Is it time to get a new boiler?
At some point, your boiler might stop heating your home as it used to, despite its regular yearly service.
If you’ve noticed that your heating experience has changed, i.e. your radiators are taking longer to heat up, or your boiler is losing pressure regularly (more than usual), it might be time to invest in a new boiler.
But before you commit to the big purchase, ask a heating engineer to check that there isn’t a build-up in your heating system preventing your boiler from working as it should.
However, If your boiler keeps breaking down, it may be cheaper, in the long run, to cut your losses and get a new one, just come to us at WarmZilla and we’ll sort you out!
When shopping around for a new boiler, we’d advise using the WarmZilla boiler comparison tool. Just select up to 3 boilers you want to compare and you’ll be able to compare key stats side by side to see which boiler is best for your home.
Why should you buy a new boiler from WarmZilla?
When you purchase a new or replacement boiler with WarmZilla, your boiler package will also include;
- Your chosen boiler, along with the necessary flue kit needed for your central heating system
- Installation by a qualified Gas Safe Engineer
- Removal of your old boiler and parts
- A FREE system cleanse of your central heating system
- Chemical Inhibitor for added protection for your new boiler
- 10-years guarantee, which will be registered by WarmZilla after installation
- A FREE magnetic system filter for ongoing protection
- The Neomitis RF Digital Wireless Room Thermostat
