The lead story of the August 11, 2014 Air conditioning Heating and Refrigeration NEWS is “Man Gets Prison Time for Venting R-22.” In this particular case he was stealing copper – he just did not bother to recover the refrigerant first. The police literally caught him in the act, and knowing what he did was a Federal violation, reported him to the EPA. Now he is serving 31 months in prison. Truthfully, most people who steal copper or vent refrigerant are not caught. However, this case proves that you CAN be caught, and there is a substantial penalty. Some people do the right thing because that is the way they conduct their lives. Others need some external reinforcement to avoid doing what they know they are not supposed to do. Without penalties for breaking the rules, these folks will ignore the them. Hopefully this incident will be widely publicized so that other potential thieves in need of external reinforcement will consider another line of work. Or at the very least, steal something that does not involve venting refrigerant.
Here is a link to the story Prison Time for Venting Refrigerant
Saturday, August 16, 2014
Sunday, August 10, 2014
Oxy-Acetylene Torch Safety
One of my e-buddies, Dave Christensen, suggested that I write about oxy-acetylene torches. He recently bought a new torch and confessed that he read the instructions before using it. In the instructions, he noticed that the regulator settings were different from the ones he had used for years. When we teach students to use torches in school, we typically teach them the regulator settings that work for the equipment we have. I am afraid we may not always make sure students understand that torch settings are not universal. The correct regulator setting depends upon the torch manufacturer, the tip size, and the application. Torch manufacturers typically provide these settings in the instructions.
There are a few guideposts that stay the same. For example, you NEVER, NEVER, NEVER set acetylene above 15 psi. In fact, I get nervous above 10. The reason is that acetylene is unstable at pressures above 15 psi and can explode. So how does it not explode in the acetylene cylinder at 250 psig? It is dissolved in acetone liquid which is stabilized in a porous core. That is why you should never transport or use acetylene cylinders on their side – it lets the liquid run out of the cylinder into the valve area. Also, you really don’t need the oxygen above 20 psig. Many tip charts have it about half that for most applications. However, the exact settings you should use are ... in the instructions!
Another common safety issue is leaving your regulators set and just opening and closing the tank valves when you want to use the torch. This is convenient and saves time, but it is dangerous. Regulators can fail because of the sudden bump in pressure. This can cause parts to fly and high pressure gas to stream down the hoses. The last thing you should do when shutting off your torch is to adjust the regulator T handles out counterclockwise until all the spring pressure is released. When the cylinder valves are opened they should be in this position. AFTER opening the cylinder valves you can adjust the regulators to he correct pressures.
When lighting the torch, you should light the acetylene first by itself and then bring in the oxygen. Opening both the acetylene and oxygen simultaneously can cause oxygen to flow into the acetylene hose and regulator if the oxygen pressure is higher than the acetylene pressure. This can create a very dangerous situation – a mixture of fuel and oxygen under pressure in the hose and regulator. The only place we want this type of combustible mixture is in the tip. When shutting down, reverse the process. Close the oxygen first and then the acetylene.
Torch manufacturers have some very good training material available for free. Here are some links to some good training resources.
http://training.victortechnologies.com/
http://www.harrisproductsgroup.com/en/Products/Equipment.aspx
http://uniweld.com/en/uniweld-videos
There are a few guideposts that stay the same. For example, you NEVER, NEVER, NEVER set acetylene above 15 psi. In fact, I get nervous above 10. The reason is that acetylene is unstable at pressures above 15 psi and can explode. So how does it not explode in the acetylene cylinder at 250 psig? It is dissolved in acetone liquid which is stabilized in a porous core. That is why you should never transport or use acetylene cylinders on their side – it lets the liquid run out of the cylinder into the valve area. Also, you really don’t need the oxygen above 20 psig. Many tip charts have it about half that for most applications. However, the exact settings you should use are ... in the instructions!
Another common safety issue is leaving your regulators set and just opening and closing the tank valves when you want to use the torch. This is convenient and saves time, but it is dangerous. Regulators can fail because of the sudden bump in pressure. This can cause parts to fly and high pressure gas to stream down the hoses. The last thing you should do when shutting off your torch is to adjust the regulator T handles out counterclockwise until all the spring pressure is released. When the cylinder valves are opened they should be in this position. AFTER opening the cylinder valves you can adjust the regulators to he correct pressures.
When lighting the torch, you should light the acetylene first by itself and then bring in the oxygen. Opening both the acetylene and oxygen simultaneously can cause oxygen to flow into the acetylene hose and regulator if the oxygen pressure is higher than the acetylene pressure. This can create a very dangerous situation – a mixture of fuel and oxygen under pressure in the hose and regulator. The only place we want this type of combustible mixture is in the tip. When shutting down, reverse the process. Close the oxygen first and then the acetylene.
Torch manufacturers have some very good training material available for free. Here are some links to some good training resources.
http://training.victortechnologies.com/
http://www.harrisproductsgroup.com/en/Products/Equipment.aspx
http://uniweld.com/en/uniweld-videos
Saturday, August 2, 2014
Stubby Gauges
Anyone who has ever disconnected a hose from a Schrader valve knows about the spray you get as a result. If you are taking a hose loose from the liquid line there can be quite a lot of very cold refrigerant spraying out. Many people don’t realize that the spray is usually NOT coming from the Schrader valve, but from the hose! The spray is from refrigerant that is trapped in the hose coming back out when you loosen the hose. By my calculations a standard 5 foot 1/4” hose holds about 3.5 ounces of R22 liquid. Releasing it is bad for the atmosphere, bad for the system, and bad for you if it gets on your skin. If the system was perfectly charged before you connected your gauges, it is no longer after you take them off. If you were to connect a 5 foot hose to the liquid line of a dorm refrigerator and fill up the hose, you would essentially suck most of the charge out into your hose and gauges. Of course you would first have to install a piercing valve or two – creating potential leaks to boot.
My point is that you don’t always need to connect your gauges to every system you see – especially small critically charged systems. Even on larger systems, if you are connecting gauges just to check the system operation, consider getting a couple of “short gauges.” These are essentially a gauge mounted on just enough tube to connect it to the system. They hold a minimal amount of refrigerant, so the amount released is much less. This saves the atmosphere, is better for the system, and is way better for your fingers. Here is a link to a picture of a set of stubby gauges used in an article on ice machine service found in Contracting Business Magazine.
My point is that you don’t always need to connect your gauges to every system you see – especially small critically charged systems. Even on larger systems, if you are connecting gauges just to check the system operation, consider getting a couple of “short gauges.” These are essentially a gauge mounted on just enough tube to connect it to the system. They hold a minimal amount of refrigerant, so the amount released is much less. This saves the atmosphere, is better for the system, and is way better for your fingers. Here is a link to a picture of a set of stubby gauges used in an article on ice machine service found in Contracting Business Magazine.
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