Many homeowners find that properly cooling and heating their home can be expensive. With more and more businesses operating online, it can be tempting to seek out a great deal on the internet. Unfortunately, you may find yourself presented with some dangers, after all, it is not as simple as buying an appliance and just having someone install it for you. A professional HVAC contractor can provide you with invaluable guidance and advice to ensure that you system best suited to your home. When you buy online, without the benefit of this expertise, there could be some severe consequences. 
Invalid Warranty:
When you buy HVAC equipment online, many manufacturers may invalidate or void the warranty. The reason for this is that the manufacturer has no guarantee that the equipment has been properly installed. Since improper installation can cause dips in performance and compromise the lifespan of the equipment, the manufacturer may be unwilling to support the warranty and any claims in the future.
Incorrect Sizing:
Unlike many appliances, air conditioners, and other HVAC equipment are not a one size fits all solution. When buying online, there is no guarantee that you are buying the right size of system. If your HVAC system is not properly sized for your home, you will experience energy inefficiency and in a worst case scenario, you could compromise the lifespan of the system. A professional contractor is needed to help you to determine which size of unit is needed for your home. The contractor will perform load calculations and advice which system is best suited to your requirements.
Improper Installation:
When the right system is properly installed, it can work like a dream, keeping you cool in summer and comfortably warm in winter. Unfortunately, even if you buy the highest quality equipment if it is improperly installed it is not likely to operate correctly or at the best efficiency. If your system is not correctly installed, it may even have a shorter lifespan, which means that it will cost you a lot more in the long term.
You are likely to find that if your system is incorrectly sized or the warranty has been voided, most reputable and skilled contractors will refuse to install the system. The reason for this is that they cannot guarantee the performance of the system and will not want to compromise their good reputation. A contractor who is willing to install this type of equipment is likely to be far more concerned about making a few dollars rather than their long term reputation.
While everyone loves a bargain, it is important to understand the costs involved with the short term savings of buying your HVAC equipment online. Although the initial cost may be appealing, cheap equipment could end up costing you more in the long term. A more realistic approach is to consider what savings can be made in the long run, with a properly sized and installed system reducing your energy bills, and maintaining optimum performance in the years to come.