1. What is a Heat Exchanger?
The heat exchanger in a furnace separates the combustion process from your breathing air. It is a combination metal chamber and passageway that starts at the burner assembly and ends approximately where the chimney vent connects to the furnace. Air is heated as it is blown across the hot metal surface of the heat exchanger. The heated air is then distributed through the house to warm the house.
The heat exchanger must have an air (and gas) tight seal to separate the gasses in the flue products inside the heat exchanger from the breathing air passing over the outside surface. This is because the flue gasses can be poisonous – such as deadly carbon monoxide – and contamination of the breathing air by these gasses pose a health risk and can be fatal.
2. Why do Heat Exchangers fail?
All heat exchangers fail eventually. This is because of metal fatigue. Metal when it is heated up expands, and when it is cooled off contracts. This expansion/contraction cycle is part of the normal furnace heating process. Over time this constant expansion and contraction has the same effect on a heat exchanger that bending a paperclip back and forth: it breaks. And when that happens contamination occurs and it is no longer safe.
While heat exchangers are typically manufactured to last between 10 – 20 years, many factors can accelerate the process of heat exchanger failure. These factors usually fall under the categories of poor maintenance, poor initial system design and installation, or poor equipment design by the manufacturer. Any one or a combination of these factors can result in a heat exchanger failing in a few short years.
3. How can you know when a Heat Exchanger has failed?
A heat exchanger must be visually inspected on a regular basis. Visual observation of light or water passing through the breach is positive confirmation of a crack or hole in a heat exchanger.
4. What tools are needed to determine if a Heat Exchanger is bad?
The only absolute way to determine if a heat exchanger is bad is to see it or visually confirm it. The old stand-by method of a mirror and a flashlight has been replaced by high tech infrared video inspection systems. This new technology has advanced the heating industry like arthroscopy has advanced medical surgery. The technician can now see places that are impossible with a mirror alone.
5. What about a Carbon Monoxide Test?
A test for carbon monoxide (CO) can be inconclusive. A test for CO reveals whether a furnace is producing CO. A furnace creating CO is a symptom of bad combustion in a furnace because unlike a car, CO is not a regular by-product of the furnace combustion process. Therefore, a heat exchanger can be breached and if the furnace is not producing carbon monoxide the breach will remain undetected.
6. What are the options if a Heat Exchanger is bad?
There are only two options if a Heat Exchanger is bad:
7. What about a Carbon Monoxide Alarm?
Relying on a CO Alarm is not an acceptable solution for a bad heat exchanger. This would be as unsafe as driving a car that has a leak in the brake line – you might be able to brake a few times but you wouldn’t want to bet your life on it. Further it is against the Mechanical Code, Fire Department regulations, and SEMCO policy to allow a furnace to operate that has a bad heat exchanger. A representative from any of these organizations would shut the furnace down.
8. Is a Heat Exchanger inspection foolproof?
Use of a mirror and a flashlight is adequate for the accessible spots, however the majority of the heat exchanger can’t be seen. If the technician uses an infrared video inspection system you get as close to fool-proof as possible short of totally dismantling the furnace and removing the heat exchanger.
9. How does Vincent’s provide the highest level of confidence possible?
There are two areas where a high level of confidence is vital for you:
To give you this assurance, Vincent’s has adopted a policy and procedure that gives you 100% confidence that their diagnosis is correct:
‘The right stuff’ – as mentioned above, all Vincent’s technicians have been equipped with state of the art equipment.
‘Trust but verify’ – even if it the hole or crack is readily apparent, a manager is dispatched to the job site to confirm the technician’s diagnosis, letting a second pair of eyes confirm the breach.
‘Reverse the risk’ – even after having a company manager provide a second opinion, Vincent’s provides you with absolute assurance with their incomparable
100% Free Heat Exchanger Warranty*:
If a heat exchanger condemned and replaced by Vincent’s Heating & Plumbing, proves upon further inspection to be good after removal, the replacement is 100% FREE!
10. Should I get a second opinion from another company?
If you are still uncertain after understanding Vincent’s policy and procedure to give you 100% confidence in their diagnosis, then by all means have another company give you a second opinion. Just be aware of the following items:
If they won’t do this, consider:
Ø Vincent’s is willing to risk a free furnace or heat exchanger replacement.
Ø The only thing the second company is willing to risk is your health and safety.
The reason that Vincent’s is willing to put up such ‘high stakes’ is because of the confidence in their equipment and their procedure.
*Note: The 100% Free Heat Exchanger Warranty is one that has never had to be invoked. But other companies that swore that there was no breach in the heat exchanger that Vincent’s discovered have learned recipes for ‘preparing crow’ when they were later shown by the Vincent’s tech where the breach in the heat exchanger was.
Copyright 2003 Vincent’s Heating & Plumbing ,Inc
About Daniel Squires