CON on this boiler means ""communications error" look for a loose/disconnected wiring harness. If everything looks good get a engineer in. It will work out cheaper in the long run and will save you a lot of head scratching.
M
July 2010
Wrong Answer
the gasser
July 2010
condenshion trap blocked or full, check the out let outside is clear first, the the trap in the boiler.
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