Three main factors to consider are:
Life expectancy of current system
Operating cost
Looking at the big picture
When you’re frustrated by an equipment breakdown, it can be tempting to find the least expensive “quick fix” to get on with your life in relative comfort. That “quick fix” may be the least expensive option now, but it may not give you the most value–or cost you the least–in the long run.
Paying for repairs on an old or inefficient system often simply prolongs the inevitable. It’s almost like putting a bandage on a serious injury. An older system that breaks down once is likely to break down again… and again. That means more emergency service calls or, worse yet, the risk of damage to your home or to other components of your heating and cooling system.