A magic bullet is a quick and simple solution to a difficult problem. Sorry to say, when it comes to heating and air, hardly ever are there any magic bullets. This poses a problem that I see over and over again, customers believe that changing out their system alone will solve all their problems. What is even worse, many technicians believe the same thing and perpetuate this belief with customers, sometimes it’s just an ill-informed technician lacking an understanding of how the house, duct work and envelope act as a system and how they all work together, and then there are the techs that knows that a customer thinks replacing their system will fix everything and uses this belief to help them get a sale, whether or not it solves the customers problems. Fortunately, our techs are trained to not use this as a sales tactic, but I cannot speak for other companies.
Here is a perfect example of the aforementioned, one of our techs found a cracked heat exchanger on a rooftop package unit and encouraged the customer to replace the system instead of repairing due to the age of the unit. The customer agreed and the system was removed, and a new system installed. However, only a few days later the customer calls to say there was a problem. The tech went out to find the customer was upset because their living room was still cold and not heating the same as other rooms in the house. Apparently, the customer always had a problem heating and cooling the living room and believed that changing out the system would solve the problem in the living room, he thought a new system would be the proverbial magic bullet.
Unfortunately, the customer did not tell the tech that there was a problem with the heating and cooling of the living room before it was decided to replace the system. Upon further inspection the tech found the ducts going to the living room appear to be too small, more on this later, and even worse the ducts to this room are not accessible because they dive into a cathedral ceiling that has no access or attic space, making replacement or repairs impossible for these ducts. The solution is to run a new supply duct to the living room and install it high on the knee wall in the attic to the living room. Technically it was the customers problem because he did not tell the tech there was a problem with the living room. However, it is the tech’s problem as he should have asked the question when going over their options and selling him a new system, is there any rooms you are having a problem heating and cooling? The customer was adamant about staying within a budget and the tech was happy to oblige by just replacing the system without a load calculation and a test in. Both the load calc and test in would have shown there was a problem with the airflow to the living room. Plus, if the tech had asked the question before working up a price to replace the system, this could have been addressed and become an included option which would have been taken care of during the change out. In this instance the tech failed to ask and the customer thought that replacing the system would fix everything.
Moreover, the ducts should be addressed each and every time when considering replacing a system, in addition to having a load calculation done. Everyone assumes that the unit was sized appropriately for the home and the ducts were also sized correctly for the rooms when they built the house or added central heating and air to it. In truth, I have found that ten percent or less of the systems I have seen had a true load calculation to determine the proper size unit for the home and then even fewer have properly sized ducts from the load calculation, they all used rules of thumb based on square footage.
So please, customers and technicians don’t assume replacing a system will be a magic bullet that will fix everything. In that same light, it takes true measurements to determine where best to apply your money that will reap energy savings and better comfort.