
If you have an older furnace, it most likely won’t be compatible with the newer coil, and subsequently, the newer outdoor air conditioning condenser. There are two components to an air conditioning system: the cooling coil or “indoor” component, and the big gray or green outdoor unit, called a condenser.

Most people don’t know that if you want to add air conditioning to your home, your furnace has to be compatible with the new air conditioning system. Most furnaces have a useful and “safe” life between 15 and 20 years. Knowing your furnace system’s age is also important when it comes to the issue of connecting it to an air conditioning system. Each of these brands have their own methods of identifying system age from serial numbers. The most popular furnaces that have many years in the field include Carrier, Bryant, Lennox, Rheem and Goodman/Amana. Knowing your system’s age is important because it can tell you a lot about whether you might be able to get by with furnace repairs or be forced to completely replace the heating system with a new one.

First, it tells you in what year the furnace was manufactured, so you can supply that information when you need furnace repair or maintenance. If you live in San Diego, there are a number of benefits in knowing how to use your heating system’s serial number.
