Error FD

Safety first

- If you smell gas, leave the property immediately and call your emergency gas number. Do not operate electrical switches or the boiler.

- Before any checks, switch the boiler off at the mains isolator or fuse spur and allow it to cool. Do not remove the boiler cover or attempt internal repairs — only a Gas Safe engineer should open the boiler or work on gas components.

Initial checks a homeowner can do

1. Look at the pressure gauge on the front of the boiler. Normal operating pressure for most Ideal boilers is about 1.0–1.5 bar (aim ~1.3 bar). If the pressure is well below 1.0 bar, that commonly triggers FD.

2. Check for visible leaks around the boiler, pipework, radiators, and any visible valves. If you find an active leak turn the boiler off at the mains and call an engineer.

3. Check radiators: if many are cold or dry, the system may be low on water or airlocked. If you have a regular/system boiler with a loft F&E cistern, check that the cistern isn’t empty or blocked.

4. Listen for noisy pump sounds (grinding/rumbling) which can indicate a blocked or failing pump.

How to repressurise the system (typical safe procedure)

- Locate the filling loop: many Ideal Logic boilers have an integral filling loop or two small blue valves under the boiler. Read your manual for exact location and type; if you are unsure, do not force anything.

- With the boiler switched off, slowly open the filling loop valve(s) until the pressure gauge rises. Increase pressure slowly and stop when the gauge reads around 1.0–1.5 bar (aim ~1.3 bar). Do not over-pressurise.

- Close the filling loop valve(s) firmly and ensure they are left closed. Wipe up any water if a small amount leaks during the operation.

- Turn the boiler back on and reset following the boiler’s instructions. If the FD clears, monitor pressure over the next 24–48 hours.

Bleeding radiators / removing airlocks

- If radiators are cold at the top, bleed them with a radiator key to release trapped air. Bleed until water flows steadily, then check pressure again and repressurise if needed. Always repressurise with the boiler off and close the filling loop when finished.

- If you suspect an airlock that simple bleeding won’t cure, do not attempt pump manipulation or internal work — call a qualified engineer.

Checks that indicate you should call a Gas Safe engineer

- Pressure will not stay up or the FD returns soon after repressurising (possible leak or faulty component).

- You find or suspect a leak anywhere in the system or the boiler itself.

- You hear loud grinding or the pump appears to be blocked or failing, or the pump was recently installed/relocated and may be incorrectly fitted.

- The boiler needs access to internal parts (pump replacement, wiring checks, PCB faults, internal component faults) or any work on gas connections.

- The boiler shows other fault codes or won’t reset after correct pressure is restored.

Final notes and when to stop DIY

- Simple actions you can safely try yourself are: checking the pressure gauge, repressurising via the filling loop, bleeding radiators, checking for obvious leaks, and resetting the boiler per the manual. Always isolate power first and take care when operating filling loop valves.

- Stop and call a Gas Safe registered heating engineer if the fault persists, if there are signs of leaks, if pump or internal faults are suspected, or for any work involving gas or opening the boiler. FD can sometimes be fixed quickly, but persistent flow/pressure faults need a professional diagnosis to avoid damage or unsafe conditions.