Ideal boiler showing F5 in Wednesbury? It usually means the return thermistor has failed. What it means and what gets replaced.
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On many Ideal boilers, F5 points at the return thermistor. That sensor reads the temperature of water coming back to the boiler from the radiators. A bad reading stops the boiler.
The sensor or its connection is the usual cause. Less often it is the circuit board. Your manual will confirm the meaning for your model.
Ideal Logic combis are a popular replacement across Wednesbury, often fitted into the same kitchen cupboards as the boilers before them. Tight cupboards and old wiring routes can make loose connections more likely.
Turn the boiler off, wait a minute, turn it on and reset once.
Mention new units, shelves or plumbing near the boiler. A knocked lead is a common cause.
The sensor is inside the case and needs an engineer to test.
Tests the return thermistor and its plug, then replaces whichever has failed.
A photo of F5 and the boiler label, plus a note on whether the radiators were warm before it stopped.
The return sensor helps a condensing boiler judge how much heat it is getting back. With a bad reading, the boiler cannot run efficiently even when it does fire. Replacing it gets the boiler working as designed again.
A code that disappears and returns later often points at a loose plug rather than a failed sensor. Note when it shows and mention it when you get in touch.
No. It is a sensor fault and the boiler has stopped safely. A gas smell is different from a fault code. If you notice one, step outside, avoid switches and ring 0800 111 999, the gas emergency line.
Yes. Thermistors for Ideal boilers are widely stocked.
Usually not, if the part is on the van.
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