Error Code 33 on Carrier Furnace – What You Can’t See

Error Code 33. On a Carrier furnace, it means restricted air flow, and I’ll never forget it. It can mean other things, but in this case, it didn’t. There really was a problem with air flow. We know that now of course, but at the time it was baffling.

I’m going to tell you a story. And I shouldn’t, because it was a lumpy path to success. After all, what company wants to showcase a failure? Nonetheless, I am going to tell you a story about a time when we got it wrong, despite being Carrier Dealers, factory-trained to service, install, and repair Carrier furnaces. Even with years of diagnostic and heating repair experience, we made a mistake.

Aren’t we invincible?

This happens to every business, no matter how hard we try. It happens no matter how much education and training, or tools and equipment we provide to our employees. Humans are…well, human. Sometimes it would be more convenient if we weren’t.

Andrea P. called us with a “no heat” complaint. “No Heat” is a common call that we receive this time of year. This one was right around Halloween actually, in 2013. She had three small children and her furnace had simply stopped working. We arrived and diagnosed a failed secondary heat exchanger. The parts were ordered, and we scheduled for the replacement of them. Any number of days without heat is always inconvenient and uncomfortable, but parts were scarce, and it took almost a month to get them delivered to our shop and return Andrea’s home.

Error Code 33

The replacement went well. It was a big job – around 6 hours, and essentially involves completely dismantling the furnace to replace a major component, the secondary heat exchanger. Once the technician was done and had it all back together, he fired (lingo for started) the furnace. It ran normally and after he checked everything over, he left. The next day, it faulted with error code 33. We returned and rechecked all the settings and tried again. Same code. After being reset, it would start normally with all settings and readings within range, and then for no apparent reason, it would fault out. It was weird. One might even say it was spooky.

Our technician Mike, had been with R&B for several years and was well versed in replacing heat exchangers. The original problem and diagnosis (readings/ carbon monoxide levels / gas pressure / visual inspection) had all been clearly defined using the Carrier template; the problem had been the heat exchanger. Before we changed the heat exchanger, the error code was not 33. So, why were we getting it now?

Error Code 33 Wouldn’t Quit

Mike called Carrier Tech Support which is a call centre of uber experts – like Steven Hawking knows about theoretical physics – who not only have nearly endless documentation and databases at their disposal, but also the latest updates, product notices, and bulletins that might be published by the manufacturer on a particular model, serial number range, or warranty issue trend. All manufacturers have a technician support portal for this purpose. The Carrier representative walked Mike through each part of his process, checking all the diagnostics again. The manufacturer recommended some additional replacement parts, and we replaced those too. On paper, the problem was solved… except that it wasn’t. Error code 33.

Days passed. Hours were spent noodling on what could possibly be wrong. Mike and R&B Owner, Rob put their heads together and the two spent a significant amount of time going over everything again. Mike even spent his own personal time researching and trying to figure it out. You might say it was haunting him!

R&B Wouldn’t Quit

Somewhere along the line, Mike located an exploded schematic of the inside of the unit which he compared to the list of parts we had received from the manufacturer. There was a part missing: The cold air baffle. It’s the type of part that is integral to the correct running of the furnace, yet so benign as to go unnoticed. The cold air baffle is a part that’s actually attached to the secondary heat exchanger. When you take the old one out, that baffle comes out right along with it, like a dust cover on a book (if it were glued on). It seems extraneous and a replacement book that arrives without a dust cover reads the same. The new heat exchanger didn’t have this piece on it, and there was nothing to indicate that it was required.

What Mike was supposed to do, was take the cold air baffle off (regardless of condition) and attach it to the new heat exchanger. He didn’t know that because this incredibly specific quirk was only applicable to a small percentage of a particular range of serial numbers in the Carrier series. We’d simply never come across it before.

When we called the supplier to order the part, they commented on how unusual it was for us to ask for one. The manager had never sold one before. But for $33.60, the part was ours and another six hours later, the furnace was running fault free. That knowledge cost 10 days, 16 hours of additional diagnostics and repair, and countless hours of frustration for our customer and confusion for us.

What You Can’t See

So, why am I telling you this story? Experience comes from making mistakes, and we learned from that, but that’s not the point. Here’s the important part. It’s not that we’re not going to make a mistake, it’s that if we do, we’re going to stand behind the work. For Andrea, we kept going back, kept trying to find solutions, kept at the job long after any profit had ‘ghosted’. We had provided a workmanship guarantee and we honoured that. That’s why I’m telling you this story. I’m proud to work at a company that doesn’t give up.

I’m happy to say that Andrea is still an R&B customer. Maybe she didn’t love the discomfort, but what she remembers is what we did about it. It’s possible that this winter you’ll be faced with a major heating repair, or a heating system replacement. You may be wondering about brand or price, but what’s really important is what you can’t see – hence the title of this blog. For Andrea, what she couldn’t see (aside from the restricted air flow!) was the peace of mind that came from ultimately being taken care of. She never had to worry that we weren’t coming back, and we promise that same thing to you. When you choose a company to trust for your heating needs, choose one that sells more than just what you can see. Choose R&B.