One thing important that you should remember is to make sure that the gas furnace heat exchanger is working well. It's true! Imagine your car after an oil change. Doesn't it run like it was brand new? That would be heavenly right?
The same goes with your furnace. The proponent of the heat is the heat exchanger. This is where the heat is produced by the burning fuel. Then this heat is transferred into the water or the air for dissipation in the house.
There are many parts on your gas furnace. But without the gas furnace heat exchanger, you surely couldn't expect any heat at all. And if you don't take care of it, you just might get a hole or a crack in that thing and cost your wallet a beating.
When there is a hole or a crack in the exchanger, the heat or the hot water escapes. It can also happen that combustion fuel escapes into the air. And that's just bad for your health.
The constant use of the gas furnace causes the gas furnace heat exchanger to crack. It is a normal thing that happens to gas furnaces. Experts even say that if gas furnaces are kept in ideal conditions, they will last longer than what is expected.
If you tend to set the thermostat too high, there are higher levels of the exchanger to get a crack or a hole in it. And the only remedy to that is to replace the part or the whole furnace itself. That will cost you a lot of money.
Damage on the exchanger usually happens some time after a few years of use. Especially if the furnace was being used all the time, you can expect that a crack or hole will form. The combustion process somehow, makes the exchanger's case brittle.
It is best to keep an eye on your gas furnace's heat exchanger. This will save you a lot of time and a lot of money from repair parts and labor. It will also save you from a lot of headaches in the long run.
In order to fix your furnace, it is best to call an expert. If it is really old you should consider getting a new one that is more reliable.
Another article you should read - High Efficiency Gas Furnace Comparison