While equipment manufacturer’s installation instructions contain essential “how to” information, engineering data contains “how much” information. Let’s take a look at what essential information is contained in this paperwork and how it can make life easier if we take time to use these installation and testing tools.
System installation involves taking a group of components and combining them with wire, sheet metal, screws, straps, piping, flues, and adhesive so that somehow a predetermined end result of comfort is achieved over a wide variety of indoor and outdoor conditions.
Face it, the odds of getting it right from your memory are probably pretty remote. The habit of taking time to design and select system components and then to verify the manufacturer’s recommendations is a highly leveraged and good use of time. Such an investment of your time may pay big dividends in meeting your objective of delivering comfort in the most efficient manner possible.
Installation Instructions
So, if I were to ask you what percent of the time installers actually read equipment installation instructions, what percent would you say? Would it be five percent, ten percent, or 30%? If I were to ask how often should the installers read the installation instructions, what would your response be? Would it be 50% or 100%?
Perhaps you may say your installers are good enough and that they really don’t need to read the installation instructions. If you were to read through a set of installation instructions from start to finish, you would be surprised by the solutions you may find to troubles you encounter weekly.
Each installation instruction contains essential information critical to the success of an installation. First there are the WARNING pages. You may think these are made for idiots, and required by the attorneys, but taking the time to read them now and then may just be what you need to save a life, or at least a limb.
In addition to general instructions and important information on electrical, gas, refrigerant connections and required clearances, you’ll find specific instructions on control wiring and sequences, safety controls, start-up and adjustment options and instructions for setting fan speed. Which of these can you do without?
The more complex equipment is these days, the more varied installation instructions become. Consider the fact that without installation instructions it is impossible to guess today’s dip switch settings or control sequences.
Perhaps if you’re installing new construction systems and installing three identical pieces of equipment a day, you might be sharp enough to forgo reading the installation instructions once in a while, beyond that, keep them handy.
Engineering Data
The quality installation process constantly refers to detailed information that you can’t afford to guess at when charging a system or measuring system performance.
Fan Performance Tables tell us about required fan speed settings and allows us to interpret fan airflow based on static pressure and fan speed.
Detailed Cooling Performance Data is the only way to be able to know if the installed system performance measures up to what we promised our customer the system would deliver when it was installed. How else can we rate the system performance with CSER if we don’t know what the equipment is expected to do under current operating conditions?
Heat Pump Heating Performance is published for each piece of equipment and BTU output may easily change up to 50% based on outdoor temperature conditions, airflow or indoor temperatures. Without engineering data, who knows what it should be?
Refrigerant charging may vary from one piece of equipment to another based on refrigerant type and ambient conditions. Using data specific to each piece of equipment and each manufacturer will go a long way to assure the quality of the end product.
Take Time for a Good Read
With the growing complexities of equipment and their controls, installation instructions and engineering data are more critical now than ever. As new equipment comes on the market, it seems the associated reference material is gaining weight with each shipment from the factory. Shouldn’t this be telling us something?
Time spent with this data whether printed or online is time well spent. Should you decide to invest in your profession and study one set of this data, you will have an increased understanding that will most likely pay off in the near future.
Rob “Doc” Falke serves the industry as president of National Comfort Institute a training company with technical and business level membership organizations. If you're an HVAC contractor or technician interested in a free report on how o interpret fan performance data, contact Doc at [email protected] or call him at 800-633-7058. Go to NCI’s website at nationalcomfortinstitute.com for free information, articles and downloads.