Please get equipment information. Tstat was satisfied at 78 and no issues found, insulation is thick in attic as well. I recommended possible replacement of six duck runs in attic due to age but not leaking at this time. I explain to customer that they may want to set their thermostat a little lower than 78 in the summer due to wood frame construction on home and age of home. Customer said she will try setting temperature lower and check it in the next couple days