Officially F05 means the pressure switch is stuck on full. In my experience, F05 means your main module has failed. This is located in the back of the machine. We can test your module for £7.20 inc return postage. If it needs repairing, we do it same-day at a charge of £59.88 + £6 postage (no charge then made for testing). Our address is on our website www.emwelec.co.uk or you can call us for free help on 01159652118 Tony EMW Electronics
www.emwelec.co.uk, July 2013