Ferroli boilers
Ferroli is an Italian heating group. It says its products are sold in more than 100 countries. Its UK company, Ferroli Limited, is based at Walton on Trent in Derbyshire. In the UK, Ferroli sells boilers, water heaters and heat pumps.
The Ferroli range
Ferroli sells one gas boiler for UK homes: the Bluehelix Hitech RRT C. It’s a combi. It comes in three sizes: 24, 28 and 34 kW. The number is on the front, as in “Bluehelix Hitech RRT 28C”. Each size has its own GC number, listed on the front page of the manual.
Ferroli says its wall-hung boilers have a stainless steel heat exchanger. You can upgrade the warranty to 10 years. Like most makers, Ferroli needs the boiler serviced every year to keep the warranty valid.
Ferroli also makes the Force W. It’s a much bigger boiler, from 60 kW up, for commercial buildings. If you have an older Ferroli at home, its manual may not be on the UK website. Ferroli’s support team can help.
How Ferroli boilers show a fault
The Bluehelix shows a letter and two numbers, such as A01 or F37. The letter tells you a lot.
- A codes stop the boiler until you reset it. Hold down the reset button until the screen asks “Confirm?”, then confirm. If the boiler still won’t start, the fault needs fixing first.
- F codes are temporary. The boiler clears them by itself once things are back to normal.
So an F code may go away on its own. An A code that keeps coming back needs a Gas Safe engineer.
Pressure and F37
Ferroli’s manual says the pressure should be about 1.0 bar when the system is cold. It suggests topping up if it falls below 0.8 bar. If it drops too low, the boiler stops and shows F37.
Once you top it up, the boiler runs an air venting cycle for about five minutes. That’s normal. Our guide shows how to top up low boiler pressure.
Frozen condensate pipe
Ferroli has its own advice on this. Its guide says to look out for three signs:
- a gurgling noise from the boiler;
- a code such as A01 or A61 on the screen;
- ice you can see on the pipe outside.
Ferroli makes one more point worth knowing. A frozen condensate pipe isn’t covered by its warranty. So check the pipe before you book an engineer. It could save you a call-out charge.
To thaw it, pour warm water over the frozen part, never boiling. Then restart the boiler. Our guide shows how to thaw a frozen condensate pipe step by step. To stop it happening again, Ferroli suggests lagging the pipe and fitting a drain cover over the end. If it keeps freezing, ask an installer about moving the pipe.
Ferroli gas boiler ranges
These are the gas boiler ranges on the Ferroli website as of 21/10/2026.
- Bluehelix Hitech RRT C Combi
Common Ferroli fault codes
Codes can differ between models and ages of boiler. Always check the user manual for your exact model.
| Code | What it means | What you can do |
|---|---|---|
A01 | The burner didn't light. Causes include no gas, or a blocked condensate trap. | Check your other gas appliances and any prepayment meter. In cold weather, check the condensate pipe for ice. Then reset once. |
A06 | The flame went out after the boiler lit. | Reset once. If it comes back, call a Gas Safe engineer. |
A08 | The overheat protection has tripped. | Check the radiator valves are open and the pressure is right. Reset once. If it comes back, call an engineer. |
F37 | The water pressure in the system is wrong, usually too low. | Top up to about 1.0 bar with the heating cold. The code should then clear by itself. |
F05 | Fan fault. | F codes can clear by themselves. If this one stays, call a Gas Safe engineer. |
Ferroli manuals
Ferroli puts its user guides and installation manuals on its own website. You can find Ferroli manuals here. You'll need your model name. The GC number helps too. Our guide shows you how to find your boiler's model and GC number.
Stay safe. You can reset a boiler, top up its pressure and thaw a frozen condensate pipe yourself. Anything inside the case is a job for a Gas Safe registered engineer.
If you smell gas, leave the building and call 0800 111 999.