incubator issues

[Crittterman]

PLEASE HELP WITH MY INCUBATOR ISSUES........

I bought two identical older looking cabinet incubators w/no name brand id,several years ago.....sold one and kept the other. The one worked perfectly for 3 years without a single issue. Well I bought a newer one and set the old one in the garage where it set for about a year and sold it......well.......
First it wouldnt get warm enough for her
So I brought it home to see what was wrong and fix it. I took it apart and resealed it at which time the heat element burned out so I replaced it
Still no heat so I changed out the thermo stat,the element heated up and then nothing ...... so I replaced thermostat,element and redid all connections .......nothing, no heat at all,Nothing! Thermostat has power,element has power but no heat or glow. dummy lights show all has power and I'm frustrated!
I wanted her to have what she paid for. now im surely past double what I sold it for in time,parts and shipping which isnt important. I'll give her money back
If I cant fix. but at this point I refuse to back down.........

Any Ideas ? Or Am I a idiot ?
Thanks