I also had Equitable Heating service my furnace and they told me the exact same thing as in other reports --that the heat exchanger was cracked and the whole thing needed to be replaced. This was 2 days before Thanksgiving and they turned off our heat in 20 degree weather (even with little babies in the house).

We decided to get a second opinion while we waited to get an appointment with them and another company came the night before Thanksgiving. They were extremely upset about the situation. They checked the CO levels in our home (our CO detector had also not gone off) and turned the heat back on. They said the problem with our exchanger would be fine for years to come without the risk of CO. We were very grateful for the heat for the holidays--it was getting very chilly in our home.