Let’s just say that you know Clifford Sonji, owner of a successful mechanical contracting firm in Rugby, North Dakota. But, it’s worth mentioning, the details of this tragic story have been changed to protect the innocent.

Recently, Sonji and his family returned from a long weekend at the cabin. Reception in the woods is bad, so he decided to leave his cellphone on his desk just this once. On Monday morning, feeling rested, he arrived at the shop half an hour before the office staff and techs. A light blinked from his desktop, indicating a message on the main phone line. He pressed the button and listened to the message as he sank into the chair with constricting heart pain.

“I’m leaving this message for Mr. Sonji, president of Sonji Mechanical. My name is Don Lewandowski; I am legal counsel for the Thompson family of 1604 Arborston Road. They were your customers.

“The Thompson family and their two dogs died last night from carbon monoxide poisoning that was quickly determined by the fire marshal to stem from a high-efficiency boiler your firm installed just four years ago. Your company’s tag is stuck to the system with no record of routine service or maintenance. Please have your lawyer call me immediately at 555-1212.”


It amazes me how so many people continue to disregard warnings that we, as mechanical professionals, deem important, urgent, or life-threatening. Perhaps some people are conditioned to act in this manner. Like eating gobs of butter, choosing not to exercise, or driving down the road after just two or three drinks.

In our industry, there are a few things that are sure to cause problems if we ignore manufacturer advice or warnings. One of these is the need for annual system checks and maintenance on condensing boiler systems.

And, yes, there are lethal (and legal) implications. Just imagine Sonji’s emotions after hearing that phone message. Would he call his lawyer or 911 first? Oddly enough, Sonji’s problem could’ve been avoided easily and he could have even profited from the endeavor. After all, his customers — like yours — pay for service contracts or service calls.

We installed our first condensing boiler 14 years ago and, ever since that first system went in, we’ve learned how to service and maintain them. Manufacturers aren’t exaggerating when they insist their condensing systems be inspected routinely. None of those manufacturers — not one — states that if the boiler’s installed properly, that’s good enough.

So, at the very least, we insist to customers that we inspect every modulating-condensing boiler we install annually. They can refuse, but then we have them sign a legal waiver, removing us from any legal risk.

I‘ll admit, there is some confusion in the industry about just how much maintenance modulating-condensing boilers require. Heck, after 14 years of installing and servicing these systems, we certainly don’t have all the answers ourselves.

What we have learned is that condensing boilers must be cleaned annually along with inspection of all moving components, especially the condensate traps.

When propane gas and natural gas are burned, any impurities within them collect in the heat exchanger. What we have learned is that the tighter the passages within the heat exchanger, the more issues these systems will have with combustion safety, if the system isn’t cleaned.

Also, when condensate traps fail to drain and water fills the heat exchanger, debris accumulates at an alarming rate. This, too, will cause safety issues.

The greatest safety risk with these systems — just as the Sonji story relates — is a deadly one. If mod-con boilers aren’t cleaned, it’s a relatively easy next step for the flames of combustion to burn a hole directly through the back of the heat exchanger. Or, improper combustion can also cause an explosion, blowing vents apart.

Each of these can indeed become what are described to courtroom jurors as a catastrophic failure, leading to a fire or lethal gas leak.

Lives are at stake when carbon monoxide gas leaks into living spaces. The poisonous gas is odorless, colorless, tasteless, and initially nonirritating. It’s also very difficult for people to detect. That’s why, as installers of heating systems, it’s our job to protect customers from these risks.

Unfortunately, there’s still broad misunderstanding among field technicians about the importance of cleaning and inspecting these boilers.


A few years ago, I walked into a near-horror story of my own. I received a call from a homeowner, the customer of a large fuel company, who told me his family had concerns about the quality of care the boiler was getting — or, more accurately, not getting. He called me chiefly because he wasn’t satisfied with the answers he was receiving from some of the other firm’s technicians.

I learned about a banging noise and an odor he attributed to the heating system. This concerned me, so I immediately sent one of my top technicians out to look at the heating system.

A short time later, the tech phoned and explained the boiler had a badly plugged heat exchanger with a hole burned beyond the back of the system and through the drywall.

I told him to disconnect power to the unit and set up temporary heat until we could replace the boiler the next day.

Photos of the removed system show how dangerous this was. Exhaust gas was freely leaving the boiler. Had the condition remained as it was, a disastrous outcome was likely right around the corner.

I’ll add that this family — now long-term, loyal customers — also had, at the time, a 5-year-old granddaughter who was sleeping in the very next room where measurable carbon monoxide was present. Clearly, things would’ve gotten worse in a hurry had we not stepped in.

What really floored me was the fuel company’s indifference to the customer’s plight. I can only imagine that they dismissed the customer’s complaints as silly or frivolous. Amazingly, the customers were repeatedly told by the fuel company that their relatively new boiler (installed seven years prior) was undoubtedly in fine condition and that no maintenance was necessary. All this was unseen, until we arrived. Clearly, the gas company wasn’t interested in service work.

Thank God this family’s neighbor is a customer of ours and that we’d properly communicated the need for routine maintenance. This was conveyed, and it probably saved lives.

So, if this article accomplishes one thing and only one thing, let it create questions for you. Have you impressed upon your technicians the need to routinely service mod-con boiler systems? Have you reviewed the maintenance records for systems installed by your firm? Are there any holes in the records? Are you and your customers at risk? It never hurts to check.

Publication date: 3/14/2016

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