An often-quoted study by the Louisiana Cooperative Extension Service Louisiana State University (LSU) Agriculture Center and the Gulf States Utility Co. is more commonly known as the LSU Study. Funny thing about this important piece of work - completed in 1984, and still the de facto statement on preventative maintenance - very few people in our industry understand its significance. Tell me I’m wrong, but that is the logical conclusion I must surmise; otherwise, everyone would promote the benefits of preventative maintenance to customers.


The LSU study sought to answer the question, “How much can I save with preventative maintenance?” by monitoring and servicing five residential systems thought to represent varying states of performance. The best-running system saved $6.38 per month. The poorest system saved $77.04 per month. The average of all five systems in the study was $32.76.

For complete information on the study and to find out what services were performed on the systems, go to this link that I found at the AireServ Website,

This early LSU study launched a wave of activity at Lennox Industries which instituted a Planned Service program for its dealers. The idea caught on, and many HVAC contractors discovered an attractive way to balance the peaks and valleys in their businesses and provide a valuable service to their customers. However, why aren’t more contractors, distributors, or manufacturers promoting this strong aspect of the industry? Is it because the study is 22 years old and thought to be too dated to be valid any longer? If so, here is another one to consider.

Pacific Gas & Electric, with assistance from Proctor Engineering, identified a number of problems with residential systems in a 1990 project known as the Fresno Study. A few examples: 40 percent of air conditioning units had a filter that was dirty, clogged or missing; 53 percent had coils that were dirty or clogged; 54 percent had an improper refrigerant charge. Any of these three are elements that could be corrected during a normal maintenance checkup. That equates to energy savings for a customer.

Not enough evidence? Really? The evidence is available. The problem is the lack of a consistent message that all can embrace, thereby allowing for a consistent message to customers. But, whose job is it to communicate and educate the customers?

John Lombardi, vice president of Comfort Control Systems Inc., Green Bay, Wis., made a good point recently. “If it wasn’t up to the contractor to be the sole educator of the customer, it would be so much better for the industry, much more helpful.”

True, contractors must educate customers and many do so with varying degrees of success. Distributors are not often in the position of contacting end users. However, manufacturers often spend millions of dollars in consumer marketing campaigns, touching the end user many times in the course of a year. Lombardi’s comment made me wonder what is it that contractors really need? Is it more fishing trips, more golf outings, more incentives to purchase product, more sales leads? Fishing is fun, but a consistent message that promotes the benefits of preventative maintenance would be a nice resolution for everyone to make in the New Year.


The benefits to contractors are well-established. Level-loading the business and potentially creating future sales opportunities by having a closer relationship with a customer is important.

Distributors and manufacturers stand to gain as contractors have fewer callbacks on systems. Improperly maintained equipment leads to premature failure of components. Therefore, fewer warranty costs. A study conducted by the North Carolina Alternative Energy Corp., now Advanced Energy, found that 90 percent of units tested exhibited some sort of energy-wasting problem after installation.

Today, residential customers are much more in touch with energy-efficiency issues. The Department of Energy (DOE) and Energy Protection Agency (EPA) are making sure of that; in fact, the DOE has had discussions about mandatory service for heating and air conditioning systems. Though it is unlikely such would ever be mandated in the United States, it is important to note that there is a very good reason behind these discussions. Preventative maintenance does reduce energy costs.

If the supporting research is too dated to be used in 2007, then perhaps it is time that some industry stalwarts step forward and reproduce the LSU study.

Promoting the benefits of service is a much easier pill to swallow than the possibility of invalidating consumer warranties for equipment that is not maintained properly. Almost all major equipment manufacturers have such a disclaimer in their current warranty literature, but very seldom seek to enforce it. If preventative maintenance is so important, maybe it is time to help contractors educate consumers.

Publication date:01/08/2007