Customer Help Section
At Flue Check, we know there’s nothing worse than losing your heating or hot water unexpectedly. Before you call out an engineer, here are a few simple checks you can safely do yourself that might save time and money.
Boiler Help & Troubleshooting Tips
Safety first:
Low Water Pressure on the Boiler Gauge
Most modern combi boilers need water pressure between 1.0 and 1.5 bar when cold.
If the pressure is below this, your boiler may lock out or fail to ignite.
What to check:
Look at the pressure gauge on the boiler front panel.
If it’s below 1.0 bar, you may need to repressurise the system using the filling loop.
Open the small taps or levers on the loop slowly until the pressure rises to 1.2–1.5 bar, then close them firmly.If the pressure keeps dropping regularly, there may be a leak or an expansion vessel issue — call a Gas Safe engineer.
No Heating or Hot Water
If your boiler appears to be on, but you have no heat or hot water:
Check these basics first:
Is your room thermostat or wireless controller switched on and turned up?
Are your radiator valves open?
Is the boiler display showing a fault code (e.g. E1, F22, etc.)?
You can check the code in your boiler manual.
Make sure the mains power and fuse spur are switched on.If everything seems fine but there’s still no heating, your boiler may need resetting (see below).
Boiler Needs Resetting
If your boiler has locked out, it may display a red light or fault code.
Try this:
Locate the reset button (usually marked with a circular arrow symbol).
Hold it down for 3–5 seconds until the boiler restarts.
If the same fault reappears, do not keep resetting — call a qualified engineer.
Frozen Condensate Pipe
In cold weather, your condensate pipe (the white plastic pipe running from the boiler to an outside wall) can freeze. This can stop your boiler working.
To fix safely:
Pour warm (not boiling) water along the outside of the pipe to thaw it.
Once thawed, press the reset button to restart your boiler.
To prevent it happening again, ask about insulating the condensate pipe.
Pilot Light or Flame Failure
If your boiler shows a flame failure or pilot fault, it could be due to:
Air in the gas supply
A blocked flue terminal
Low gas pressure or ignition issue
What you can do:
Check that other gas appliances (like your hob or fire) are working.
If they’re not, it could be a gas supply issue — contact your supplier or call a Gas Safe engineer.
Radiators Cold or Unevenly Heated
If some radiators are warm and others stay cold:
Try bleeding your radiators to release trapped air.
Top up the boiler pressure afterwards if needed (see above).
If radiators still heat unevenly, your system may need balancing or power flushing — we can help with that.
Boiler Keeps Switching Off
Common reasons include:
Low water pressure
Air in the system
Faulty thermostat
Pump or flow issues
If you’ve checked the simple things and the problem persists, it’s time to book a service to avoid damage or inefficiency.
When to Call a Gas Safe Engineer
If you notice:
The boiler leaking water
Unusual noises or smells
Persistent error codes
Pressure constantly dropping
Then it’s best to contact a Gas Safe registered engineer like Flue Check.
We’ll diagnose and repair the problem safely.