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Answered - Duel Fuel Engineer (Former Employee) - Cardiff
Know your gas and electricity procedures and also health and safety protocol.
Answered - Dual Fuel Engineer (Current Employee) - Northwest England
Know your stuff
Answered - Dual Fuel Engineer (Current Employee) - North West England
Don't bother preparing, don't go if you have common sense the company is a scam
Answered - Smart meter engineer (Former Employee) - England