Monday, October 22, 2012

75th Annual RSES Conference

The 75th Annual RSES Conference is coming November 14-17 at Isle of Palms South Carolina. RSES has been in the business of training and educating HVACR Technicians longer than most other industry organizations have been in existence. Note that this is the 75th Conference. RSES is really the only national organization whose sole mission is providing training and education for HVACR technicians. The conference has an impressive lineup of speakers and training sessions. If you live on the east coast, this is a chance to attend a major educational conference specifically for HVACR without traveling to Las Vegas or Colorado Springs. There is still time to register. You don't have to be a member of RSES to attend the Conference. However, while you are there, you can join if you like what you see. Click on these links for more information

RSES 75th Annual Conference

Conference Schedule

Sunday, October 14, 2012

Service Tech's Secret

Most of the truly outstanding technicians that I have met have one thing in common – they read a lot. Reading is their trade secret. One example of this is Chris Mohalley. He is the Genteq™ Certified Master ECM Trainer. He has created a nationally-recognized ECM training program and he travels the country spreading the ECM gospel. He serves as a NATE Technical Committee SME, a NATE proctor and ARI Chief EPA Examiner. He holds so many NATE Certifications that his shirt looks like a quilt. In short, he knows his shit. So I asked him one time how he became so erudite. His response, he reads a lot! Personally, I try to read something related to my field every day. At least once a week you should find something that peaks your interest and dig a little deeper. Information is now easier than ever to access. Take advantage of it! The amount of information that can be readily accessed on the internet is really staggering. When the EPA “Final Ruling" on ozone depleting substances was published in May of 1993, I had to go to the library at the University of Georgia to view it in the Federal Register. Now you can pull up the Federal Register online anytime you want. If you are not familiar with the Federal Register, it is the official government publication containing all the announcements, pronouncements, and new regulations of all Federal Agencies. This is where they post proposed rulings, and what are called “Final” rulings. Basically, a “Final Ruling" means that now it is law. There will definitely be more rulings to come. If you want to know exactly what the rules really say without any filtering by someone else, you want to read them for yourself at the Federal Register. That said, the Federal Register is some of the most tedious reading I have ever seen. Further, there is a lot of it. The Federal Register is published weekly. In its paper form, it is about the size of a phone book for a city the size of Athens Georgia. In other words, it is might be possible to read ALL of the Federal Register by yourself, but that would be about all you did. Thankfully, search engines let us look for all the juicy parts without reading the entire tedious tome.

Thankfully, there are many outlets for HVACR information which are really interesting, such as the RSES Journal. This month’s Journal has a great article on micro-channel coils and why manufacturers are looking at using micro-channel evaporator coils. You might even pick up a copy of a text, like Fundamentals of HVACR and read it one unit at a time. At one unit a week, you will finish the book in a little over a year and a half – there are 92 Units. You can pick up a lot just by looking at the material posted by manufacturers and distributors online. One caveat on web surfing – realize that the freedom for anyone to publish on the web means that there are products, policies, and procedures espoused that may not be in your best interest to pursue. A case in point: the flammable R-22 replacement refrigerants that are NOT EPA approved. They are mixtures of propane and butane. They absolutely should NOT be used to replace R-22 in an existing system. Remember, nothing in that original system was designed with a flammable refrigerant in mind. Always look to see who is posting the information. If you read a lot you will learn to sort out the fact from fiction. Thanks for reading!

Sunday, October 7, 2012

Check the Draft

With the arrival of Fall weather technicians will soon be taking Fall furnace checkup calls. One of the things we should be doing is checking the vent draft pressure to insure that the vent is working properly. While many technicians are careful to check for cracks in heat exchangers, they sometimes neglect the vent. I believe that improper venting occurs far more often than cracked heat exchangers. Further, a vent that is spilling into the house has the potential to release far more vent gasses into the house than a crack in the heat exchanger. Of course it is right to check for cracks in the heat exchanger, just don’t neglect the vent operation. For all Category I furnaces, the vent should be a negative pressure. That is, it should be at a lower pressure than the room the furnace is operating in. Typically we want at least -0.02” wc. In other words, the vent pressure should be 0.02”wc less than the room pressure. This is true even with fan assisted Category I furnaces, which nearly all 80% AFUE furnaces are today. The fan helps pull the combustion gasses through the heat exchanger, it is NOT designed to PUSH vent gasses through the vent. Typical Class B vent is not air tight. If it is pressurized, it will leak out combustion gas.Even with fan assisted furnaces, the vent is supposed to operate at a negative pressure and the vent gasses leave because of their buoyancy compared to the surrounding air.

What can cause a lack of draft in a vent? One of the main culprits is lack of combustion air. The operation of the burners and the vent system can remove air from the room faster than it is being supplied, causing a negative pressure in the room. In older, leakier homes we often relied on infiltration for combustion air. Today, you really should provide outside air to the appliances. I have seen the operation of a furnace pull smoke out of a burning fireplace. There was enough air for the fireplace, but not both the fireplace and the furnace. The room went so negative that the fireplace vent was not lower than the room pressure. If the vent gasses cool off too much in the vent pressure will increase because the gasses are heavier, decreasing the draft. This can be a particular problem when replacing an older furnace with a newer one. Often, the vent is too big for the new furnace, causing the flue gas to cool off too much as it travels through. Another possibility is a plugged vent or vent cap. The flue gasses back up in the vent and then start to spill out of the appliance. 

Although most Category I furnaces with draft inducer fans have draft pressure switches to shut off the burners if the draft pressure is not at the minimum setting for the switch, I have seen furnaces operating with a positive vent pressure continue to run. Draft switches are, after all, switches and can fail. So don’t assume that because the draft switch is closed, the vent pressure is OK – measure it so you know.

Tuesday, October 2, 2012

Eco-Friendly Cooling

The folks at Greenheat in Australia wrote to remind me that there are ways to keep cool without using so many kilowatts. What follows is a short article from them on keeping cool the Green way.


Eco friendly ways to cool your home

Maintaining a comfortable temperature inside your home during fierce summer heat using eco friendly methods is often viewed as a faintly impossible ask. Many people are still labouring under the false impression that the only way to get proper relief from the heat is by installing a gargantuan, decidedly non eco friendly air conditioning unit. Sorry, environment. We’re too hot to bother with you.

Good news, lovers of cool temperatures and the earth. You can have it both ways. By implementing some of the measures suggested below, you’ll be minimising your impact on the environment without compromising your own comfort during the warmer months. To learn more about eco friendly ways to cool your home, visit Greenheat.

Let’s look at some eco friendly ways to cool your home:
  • Keep the heat out! Seems obvious, but by properly insulating your home, ensuring your windows and doors are properly sealed, drawing the blinds at sunrise, and cutting down on your use of household appliances like washing machines, ovens, and stove tops, you’ll significantly reduce the amount of heat within your home.
  • Become an Ivy Leaguer- covering your external walls with greenery is an effective and beautiful way to insulate your home from the punishing effects of hot weather. You’d be surprised at just how effective a measure this can be. Green walls can cut the surface temperature of walls by as much as 10 degrees Celsius.  Additionally, they help to filter air pollution.
  • External shades and blinds- external blinds and shades are more effective than internal shades and blinds, simply by virtue of the fact that they block the solar energy before it hits your window.
  • Split system air conditioning- inverter split system air conditioning units fluctuate according to the air conditioning requirements throughout the day. This makes them an energy efficient air conditioning option, minimising energy consumption by as much as sixty six percent.