Performed diagnostic on upstairs 23yr old Lennox unit, upon arrival customer stated unit wasn’t working , stated last night unit was making loud banging noise and also had a electrical smell, checked tstst, cycled to heat mode, out door unit started up, upon checking pressures found unit low, recommend leak search, customer stated his ac unit went out during the summer and he added refrigerant, system ran for 4days and stopped cooling again, explained with a heat pump, if ac is not working heat mode is not gonna work, switched tstst over to emergency heat to get gas to run, upon inducer starting up making loud banging noise, inspected inducer, failed barring , gave option to replace inducer, customer declined, blower wheel impacted, recommend pulling and cleaning, recommend TE Flood protection such as wet switch, to prevent ceiling damage, went over options with customer, highly recommended install supervisor due to age and condition of system, customer schedule for November 6 as close