Don't feel bad. Last week I got the bad news that my central heating unit has to be replaced. $3500+tax. I've been playing temperature guardian with the gas logs fireplace for the past week 24/7 while I'm home which means little sleep at night and I still have another week to go til they can get me a new unit. I'm no hvac guy but they showed me where something cracked inside the existing unit which was causing carbon monoxide to leak out and the thing to not blow heat.