A Weighty Matter

One day while I was setting up for a lab I noticed that two of my scales did not agree. What was worse, the discrepancy was significant, enough to make a system charge way off. One of the advantages of using electronic charging scales is the confidence that you have put the correct amount of refrigerant in the system. If you don’t trust your scale, you lose that advantage.  I got a third scale to try and determine which was correct, but then I thought, how do I know ANY of these are right? Maybe I have two incorrect weights, not one. So I visited my friend Jimmy in the physics lab and asked for a weight. He gave me a 2 kilogram weight. I placed the 2 kilogram weight on the scale that I suspected of being off, and it weighed 2.3 kilograms. I then moved the weight to the scale that I thought was correct, and it read exactly 2 kilograms. This restored my confidence in my good scale and verified my suspicions about the bad scale. While this simple test does not replace NIST certification, it is a simple way to keep an eye on the accuracy of your digital scales and maintain your confidence in their readings. I do not believe most  digital charging scales can be calibrated in the field, you have to send them into the manufacturer. But you can periodically check their accuracy. You may be wondering why I chose a 2 kilogram weight. Well, physics teachers work in SI, not inch pounds. Jimmy does not have any 2 pound weights. Nearly all science today Is done in SI units, not English units. If your school has a physics lab, you might want to pay them a visit. They have lots of cool toys. After all, air conditioning is really just applied physics. 

Verify

How do you know if your students have actually learned the material? Most teachers verify the results using tests. You check the student’s knowledge against a standard. If the student falls short, you provide some remediation and then test again until they meet the standard. In education, you would not assume that someone has mastered a subject simply because they read a book that had all the material in it or attended all the right lectures. You verify that they have learned the material using written tests, lab exercises, or some combination of both. How do you know that an air conditioning system performs efficiently as designed by the manufacturer? For many people this has involved using design using tools like ACCA Manual J and D, and installation using skilled personnel. These two steps are certainly important, but they can be compared to reading the book and attending the lecture. Without testing to verify your results, you really cannot be sure that the system is performing correctly. After installation, system performance should be verified by testing crucial system operating characteristics. The 2010 ACCA Quality Installation Standard provides a good format for keeping track of all aspects of a quality installation that need verification. Verification is becoming a very big deal in our industry. Increasingly, energy codes, utility rebate programs, and government programs such as Energy Star are insisting on performance verification. It is no longer enough to install a high SEER unit, you must now test and seal the ductwork and test system performance against manufacturer specifications. You can download the ACCA Quality installation Standard from their website https://www.acca.org/industry/quality/quality-installation

We the People

Happy Birthday USA! We celebrate July 4^thas the start of our nation. More correctly, it was the official start of the rebellion with the Declaration of Independence. We would not be the United States of America until nine out of the 13 states had ratified the United States Constitution. The Constitution was signed on September 17, 1787. However, it stipulated that it had to be ratified by 9 of the 13 states before it would take effect. Some states were concerned that the Constitution did not specifically reserve powers not mentioned in the document for the states. The Bill of Rights was proposed as a solution. If these states would ratify the document, they were assured that the Bill of Rights would be quickly passed. On June 21, 1788, New Hampshire became the ninth state to ratify the document, and it was subsequently agreed that government under the U.S. Constitution would begin on March 4, 1789. On September 25, 1789, the first Congress of the United States adopted 12 amendments to the U.S. Constitution--the Bill of Rights--and sent them to the states for ratification. Ten of these amendments were ratified in 1791.

The point of the brief history lesson is that the whole process from inception to the start of the first congress was based on representation. The US Constitution starts with the phrase “We the people…” Not we the chosen, we the wealthy, we the powerful, or even we the elect, but we the people. Elected representatives wrote and signed the Declaration of Independence. Elected representatives wrote and signed the Constitution. Elected representatives in all 13 colonies eventually ratified the Constitution. And finally, elected representatives voted on the Bill of Rights. All were elected representatives from their respective colonies. The men that signed these documents put their lives and fortunes in peril. Had they been captured by the British, they would have been tried for treason and hanged. Had they lost the revolutionary war, they would have lost all.

My challenge to all of you is to learn more about your country. A good place to start is at the links in the article above. And during the next election, learn about the candidates and issues and vote. To remain we the people, we the people have to participate.

Locking Refrigerant Caps Now Code

I want to point out a relatively new provision of the International Mechanical Code and the International Residential Code – a requirement for locking refrigerant caps. In the International Residential Code the provision reads “M1411.6 Locking access port caps. Refrigerant circuit access ports located outdoors shall be fitted with locking-type tamper-resistant caps.” Since the IRC has become so common across the country, there is a good likelihood that your area requires locking access port caps. If you are like me, that may come as a surprise. The primary reason for the requirement is to discourage people from releasing the refrigerant and huffing it to get a quick high. Before you all go out and start snorting refrigerant, let me first tell you what it does. Basically, it deprives you of oxygen and you feel lightheaded and dizzy as a result. That is all the high is - dizziness from oxygen deprivation. Since it deprives you of oxygen, too much for too long and you die. Since refrigerant is heavier than air, once you have filled your lungs with refrigerant, it is hard to get it to leave so you can replace it with air. I first heard of this way back in the ‘70s when people would do just about anything, including smoking bananas and sniffing refrigerant. I thought it had gone away with so many other crazy ideas of the 70’s. However, there is an alarming increase in the number of people sniffing refrigerant. The mother of a teenage boy who killed himself huffing refrigerant has founded an organization called UPROAR which works to prevent similar tragedies. So where can you get these caps? They are available at wholesalers and also online. You can read more about them at NOVENT, or AirTec.  Here are a few links to different tragic stories where people died from inhaling refrigerant.  

UPROAR - many stories on this site.

Coral Springs Florida

Dust Off

Inhalent.org

Are You Becoming Obsolete?

There is certainly a lot of change taking place in HVACR! New refrigerants to replace old standards and  even newer refrigerants to replace the new refrigerants. Variable capacity compressors, communicating control systems, and communicating thermostats that look like an I-pad. It is tempting to say, no thanks, I will just stick with my R-22 units with single speed compressors operated by contactors that are controlled by mercury bulb thermostats. And yes, many of those are still around. However, if you choose to specialize in only retro technology, you are choosing to become obsolete. Technology changes whether or not we want it to. If your job is to install and service air conditioning equipment, you need to be familiar with what is current, or eventually you will be out of a job. I remember many years ago a technician in a parts house declaring that he simply refused to work on heat pumps. He basically was saying it was too much bother to learn about them, so he would just keep working on natural draft gas furnaces and air conditioners. He would not be doing much today because most the systems in this area are heat pumps and the rest are induced draft furnaces. What he was comfortable with just does not exist anymore. As technology changes, we have to adapt. Studying is just part of a technician’s job. I read about what is going on in the HVACR field almost every day. There are so many resources now. My favorite is the RSES Journal, but I also really like the Air Conditioning Heating and Refrigeration News. I will even pick up a book on occasion. Yes, I realize that reading printed material is somewhat old school, but both publications also have on-line articles. And there are always blogs. If you prefer face to face, find a local RSES chapter. The point is we all have to be students to stay current. Otherwise, we become as obsolete as mercury bulb thermostats and natural draft furnaces.

Are You Working Hard?

The summer heat is upon us. I truly hope you all are busy. Busy is good. It certainly beats not having anything to do. However, have you ever wondered how much of your business is tied to the way you do things? Although nobody can give you any more time, you often can use your time more efficiently, which has the same effect. Learning to use your tools more effectively is important in any field. One example in teaching is designing, giving, and correcting tests. I have had quarters where at the end of the quarter I would have a box that a case of 10 packs of printer paper comes in full of paper tests to grade. I emptied it out printing the tests, and then filled it again after the tests had been taken. I still give written finals, but all other tests are on line. Using the test database built into MyHVACLab, I can build a test quickly. Better, I don’t use any of my time or any class time taking the tests. Best, I don’t have to grade a huge box of tests every few weeks. Even if you want to write all your own questions, keeping them in a test database still makes sense. You don’t duplicate effort because you can re-use your own questions. Even for my written finals, I use the database to generate the test. Instead of using class time having my students take tests, I try to use the time going over tests that they have taken. Nothing sears a piece of information into your brain like learning you just missed it on the test. Tools can be the same way. You can keep on doing the same things in the same way even when there is a more efficient way to use the same tools you already use. I have met many people who did not know that the “extra” lines inside their gauges were saturation temperatures. Essentially, a PT chart built right on their gauges staring them in the face. Digital gauges take this to an entirely new level of accuracy and flexibility, but even analog gauges normally have a few of the most common refrigerants on them. Spending a little extra on truck stock can save a lot of time. If you have the parts you need on your truck, you can do two calls in the time it takes to diagnose the problem, go get the part, and then return to put it on. Whatever you work hardest at, spend a little time analyzing why you do what you do and asking if there is not a more efficient way. The time you spend will be saved many times over.  

Ride All the Rides

Summer is approaching quickly. Undoubtedly, many of you will spend some time at an amusement park, water park, or other recreational establishment. Many parks now have a single price for admission that lets you ride all the rides as many times as you like. After paying the price of admission, most folks try to ride as many rides as possible to get their money’s worth. I can remember planning out my day at Disney World so that I would make the most of my time. I can see many of you smiling because you have done the same thing and planned a manic day at a pricey amusement park so you would get your money’s worth. So here is my question. Why are we so intent on getting our money’s worth at an amusement park, but beg to be cheated in education? When you pay your tuition for the semester, you are paying to ride all the rides. Every lecture, lab, online assignment, and test is available for the price of admission. If you think tuition and fees are high, why would you not take full advantage of all that you paid for? Try reading the assignments more than once. It does not cost any more, and you get more out of the assignment. When you miss a lecture, lab, or assignment you are cheating yourself. Not only are you not taking advantage of the services you have paid for, but you are also limiting your earning potential later on. My brother Richard has a saying “work hard at school, or work harder all your life.” HVACR is a very performance based industry. If you can’t perform, you won’t last long. HVACR is also a very technical field. To excel, you need to understand the systems and how they operate. Sure, without a lot of training you can get a job holding the other end of heavy things or running to get tools for other people. But without training or education, you won’t advance much past that point. There are many ways to educate yourself, but the easiest and fastest is to go to school. Throw yourself into your studies. Attend all the lectures, read all the assignments, and do all the labs. Ride all the rides!