The typical comfort call to a HVAC dealer goes something like this: “I have rooms in my house that never get cool”, (or vice versa in the winter). The typical response: “We’ll send a service guy to check your system for you.” That check generally consists of a basic systems inspection involving Freon levels, blower motor operation, age of equipment, basic temp measurements, tissue airflow test and thermostat placement. As many of us know, just these methods generally won’t reveal the true source of the problem – but don’t blame the service tech! The techs are limited in the field both by training and the tools they carry on their truck. When our service techs are properly trained to understand the home as a system, they’ll need a few tools that aren’t on the typical service truck to correctly evaluate comfort problems.
The Capture (Flow) Hood
In every other sector of the HVAC industry, air balance is considered a “no brainer”- an essential piece of the HVAC equation, but in the residential sector, air balance is typically regarded as unnecessary. If your techs are not using airflow measurement as part of their comfort evaluation process, there is a good chance they are mis-diagnosing the problem. Since balancing a residential system is something that is rarely done, and even less often done correctly, it’s a good bet that most of the homes you visit could benefit from this service. The only way for the tech to know if airflow is causing a comfort problem is to measure it. Without knowing that the total and room-to-room airflow are correct, it is hard to guarantee that yearly maintenance and service will provide optimal system performance. In addition to these things the flow hood can be used to measure and verify that both local exhaust and whole home ventilation are meeting current ASHRAE Residential Ventilation Standards.
Duct Tester
Today as residential building codes catch up with Energy Star and other green building standards, attention is turning to duct leakage. In the new construction world, many municipalities now require some form of leakage testing for ducts outside of the conditioned enclosure. Since duct leakage is just now becoming a required test and only for ducts outside conditioned space, it is safe to assume that most homes we encounter suffer from some type of duct leakage. Building codes focus on duct leakage outside the enclosure because this is where the most noticeable energy penalty occurs and can add up to a significant chunk of the utility bill. The reality for us as comfort practitioners is that all duct leakage matters. Any duct leakage, whether inside or outside the conditioned enclosure results in failure to deliver conditioned air to its designed location. As air slips out to unintended areas of the home, those areas get over-heated or over-cooled while the intended areas remain under-served. The ability to measure and quantify this loss allows your techs to accomplish two things. First it allows them to understand how much duct leakage a system has. Once they become familiar with the metrics used to quantify the leakage, they will be able to understand how impactful it is to the overall comfort of the home and whether a remedy should be prescribed. It also gives them a meaningful way to talk about the impact of the duct leakage with the homeowner. Once duct leakage is under control the flow hood can be again used to figure out which areas need more air and which ones are getting too much.
IR Camera
Infrared technology has come a long way in the past 6-7 years. Gone are the days where having an IR camera at your disposal means a $20-40k piece of equipment in a suitcase-style case. Today there are quite a few good options like these on the Tru Tech Tools site, that fit in the palm of your hand for well under $1,000. With some basic training our techs can use the IR camera in the home to detect thermal anomalies that could be causing comfort issues and warrant further investigation. A quick thermal scan often quickly leads to the discovery of things like missing or defective insulation, possible moisture issues and unseen thermal bypasses. Bad breakers, bad bearing in a blower motor, blown condenser disconnect fuse and some duct leakage are other useful things that can be discovered using an IR camera.
Manometer
This one may seem like a no-brainer to many of us, but you might be surprised by the number of times I see techs who don’t carry – or carry but rarely use a manometer. The manometer can be used to measure and evaluate many different things including the holy grail of HVAC measurements, static pressure. Static pressure is the blood pressure of the HVAC system. Without the ability to build a pressure profile for an HVAC system there is no way to know if a system is operating at its rated capacity or if it just seems like it is. Static pressure testing will allow our techs to eliminate problems in the system as part of comfort problems, or identify the need for further system diagnostic as part of the comfort investigation. In addition to static pressure measurements, the manometer can be used to make sure rooms with doors that close are getting the proper return air. When used in conjunction with a blower door (another great tool to have on your truck or have access to) it can be used to determine how connected rooms are to the outside.
Zip-It® Drain Cleaning Tool
This handy dandy tool will serve as a side-wall insulation inspection tool. By removing an electrical outlet or switch cover, you can slide the Zip-It alongside the box into the wall. If there is insulation in the wall the Zip-It will grab a few fibers on the way out. Insulation verified, or not. Uninsulated wall cavities can be one of the largest energy and comfort losses in a home.
By providing your service techs with proper tools and training you allow them to better diagnose comfort complaints. Tools without the proper house–as-a-system training or the training without access to the proper tools do your techs no good. They must have both ongoing training and the right tools to succeed as true comfort and system performance specialists.
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- The Tools to Set Your Technicians Apart from the Competition - December 26, 2016