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The Last Word: It's CO Season Are You Ready?

As the leaves change colors and crisp fall nights descend upon us, the spectre of carbon monoxide (CO) hangs over homes all across the country. The familiar smell of dust burning off heat exchangers is a grim reminder that we’ll soon see more news stories about families severely injured or killed by this silent killer.

So what can you do about it? Everything! HVAC contractors are in a better position to prevent CO poisonings than anyone else. The key is using a two-pronged strategy that minimizes the chance of this happening to your customers. The first prong is prevention, the second is monitoring.

It’s actually quite easy to prevent CO, as long as your technicians are armed with the tools and knowledge to evaluate and take appropriate measures to make your customers’ homes safe. It begins with following a protocol that starts from when they enter the home. Technicians should check for potential causes of CO, and measure levels in the equipment and flues. They can also check levels from ovens, gas fireplaces and dryers. The next step is to identify the true causes of high CO levels, including incomplete combustion, insufficient combustion air, bad flues, and so forth.

Sounds simple, right? Unfortunately, less than 5% of all technicians have the knowledge or instruments to do this correctly. Are your technicians in that 5%?

While prevention through testing and ongoing inspections is vital, it’s not always enough. Anything can happen between inspections: a brick can fall down a chimney, a dryer vent can get plugged, an outside air intake can become blocked, and so on. So how can you further assure your customers are as safe as possible year round? Make sure they have a high quality, functioning low level CO monitor.

Store bought detectors are designed to alert “normal, healthy adults” of lethal levels of CO. In many localities, it’s code to have a “UL listed” CO detector, so you must have at least one to comply. Unfortunately, compliance doesn’t necessarily safeguard your customers. A low level CO monitor is the best early warning system to alert customers before CO reaches dangerous levels that can injure or kill them.

The key to avoiding these tragedies is to be proactive and not shy away from this serious and growing problem. Invest in the training and tools for your field people, and the rewards will be plentiful, both financially and personally. I’d like to share with you an excerpt from a letter I recently received that really sums it up well:

“Mr. Guarino, when I entered an elderly couple’s home during a heating inspection this week, the reading on the meter was well over 400 ppm. I quickly instructed the occupants to leave at once as I opened all the windows. When the fire department arrived they found a bird’s nest in the roof stack. After the nest was removed and the “all clear” sign was given, I entered the house and examined the furnace.

I performed a CO test and found the furnace safety vent switch was bypassed/jumped. I corrected the problem and made the repairs. Because the vent pressure switch was altered the furnace didn’t shut down when the flue pipe got clogged.

According to the doctor who examined the homeowners, one more day at that exposure and the couple would have been dead. Today they’re alive thanks to God and Jim Davis, who taught me the correct way of checking and conducting a CO test. I believe this teaching and knowledge are vital to the safety of both HVAC contractors and home owners alike. I actually saved an entire family from sure death from carbon monoxide by performing this test.

I have performed about 20 CO tests on gas furnaces this season, and every time the customer was very impressed. If it were not for this training I would not have performed that test and the family would have been dead. With tears in their eyes the homeowners and their family thanked me for saving their lives.

I’m writing to thank you and tell you I believe that this training is so vital that I wish everyone in the business, including every one of my competitors, would take it. — William Acosta, Real Comfort, Philadelphia, PA.

Dominick Guarino is chairman and CEO of National Comfort Institute (NCI), ( a national training and certification organization teaching Air Diagnostics and Balancing, Carbon Monoxide Safety, Combustion Analysis and Tuning, Performance-Based Selling, and more. Email him at [email protected] or call NCI at 800/633-7058.

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