Your blower motor aka your fan then blows air over this heat exchanger. We have talked a lot about furnace failures, repairs, and replacement in our blog and we want to go more in depth about furnace heat exchanger design, how they work, and why they fail. A damaged heat exchanger in a gas furnace is potentially dangerous to a homes occupants and should not be ignored. In order to help you avoid these safety issues, today were going to talk about how a heat exchanger develops cracks and what you can do to prevent or identify the problem before its too late. Dec 03, 2018 but lets be clear if there are any cracks in an exchanger it needs to be replaced, there should not be cracks in a heat exchanger. A combustion analyzer gives us co and oxygen readings. The furnace heat exchanger is the one of the main components inside the gas furnace and its used to transfer the heat from the gas burner to the warm air thats blown into your home. One problem you can encounter with a furnace is a cracked heat exchanger. When the burners of the furnace come up, they generate hot combustion gas which is collected inside the heat exchanger, which is a metal chamber or series of chambers. Furnace with a cracked heat exchanger and flame rollout. If a crack makes its way through the walls of your heat exchanger, dangerous carbon monoxide fumes can leak into your homes air. The blower fan of the furnace then comes on and sends air around the. If a heating contractor finds a cracked heat exchanger and says the furnace needs to be replaced, theyre not pulling a scam unless theyre just outright lying to you about finding a crack.
It is important that the heat exchanger is taken care of as hazards can build from a faulty exchanger. The longer your system operates with a cracked heat exchanger, the worse the cracks will get. The cracked heat exchanger because the metal of the heat exchanger expands and then contracts as it heats and cools, the stress may eventually cause a crack to form on the exchanger. If it cracks after the warranty is up, usually at least 20 years, consider replacing the entire furnace. Cracked heat exchanger issues will affect how your heating system performs. A heat exchanger crack in a residential furnace large enough to cause trouble usually upsets a steady flame orcauses the burner flames to roll out the front of the burner openings. Home warranties and cracks in your furnaces heat exchanger. The heat exchanger is cracked or otherwise has an air leak. Very few, if any, furnaces with a typical small crack or hole in the heat exchanger. How to determine if a furnace has a cracked heat exchanger 1. A furnace with a cracked heatexchanger is usually an exception, because of the cost of the repair. Read our blog to learn what to do if this happens to you. Dec 23, 2019 in a home heater, the heat exchanger heats up the air that travels through the ventilation system.
Heat exchanger crack the heat exchanger is a key part of the furnace and is responsible for the actual heating of air. Basically, the heat exchanger is where the furnace heats the air. If the heat exchanger is cracked, byproducts of the combustion process that takes place within the. The appearance of a black carbon buildup on the furnace. Many companies use infrared light to detect cracks, but a flashlight is sufficient for more noticeable cracks. If there is a crack in the furnace s heat exchanger, there will be some signs and symptoms that are normally evident concerning the furnace. In most cases, the flue gases in your furnace will not contain carbon monoxideits not a typical byproduct of gas combustion in the furnace. Every cracked heat exchanger needs to be replaced, either by replacing the heat exchanger itself or by replacing the entire furnace. The american gas association has even put this in writing they say any visible crack or hole is reason. Heating and air conditioning contractors rarely find furnaces with cracked heat exchangers.
This one takes apart the ruudrheem heat exchanger to inspect the. Regardless of why it cracked, the heat exchanger needs to be replaced. Even though your furnace may look and seem fine, dangerous gases could leak into your home and seriously affect, even kill, your family members. This article is about ways to determine if a gas furnace has a cracked heatexchanger. Simple furnace heat exchanger test hvac learning solutions. The heat exchanger is a metal container inside the furnace that collects hot combustion gas from the burners. I show how a furnace reacts when there is a crack in the heat exchanger.
Have you heard this one recently, you have a cracked heat exchanger and your furnace has to be replaced, today. The main reason why a heat exchanger becomes cracked is due to the unit overheating. Heat exchangers are built to last 10 to 20 years, but that period could be shorter if an hvac system is used more often than the norm. Its the most common cause of excess carbon monoxide in a home. Cracked heat exchanger on lennox furnace we had a technician come out today to diagnose a problem with our furnace and upon inspection he noticed that there was a crack in the heat exchanger and the blower control board needs replacing the original problem. If our team finds a cracked heat exchanger, they cannot legally allow the heating system to continue running because of the danger and the. If the furnace isnt getting sufficient airflow, the exchanger gets too hot and literally cracks under the pressure of continual expanding and contracting. Signs and symptoms of a cracked gas furnace heat exchanger. Nov 05, 2019 a dangerous furnace problem that cant be ignored what causes a heat exchanger to crack. Furnace heatexchanger crack signs your furnace has one. But the decision to repair or replace a heating unit can be difficult. The crack is open when the heat exchanger metal is at or close to room temperature.
A cracked heat exchanger is the most common reason carbon monoxide or toxic gasses may escape into homes using a gas furnace. We find some cracked heat exchangers from the pilot lights that are blown out. I open up the plenum and show the crack from the top. Signs and symptoms of a cracked gas furnace heat exchanger change in flame appearance. The reaction between the combustion gas and metal over time may create. Heat safety is paramount so have your furnaces inspected immediately for a cracked heat exchanger. Its comprised of a set of tubes or coils that repeatedly loops through the airflow inside the furnace to heat the air.
A well qualified hvac technician will look for a furnace cracked heat exchanger during a maintenance check. The trouble comes in when we think that looking for cracks in the only or even primary method of finding co issues with a furnace. Mar 11, 20 our recommendation on finding a crack in a heat exchanger will always be to replace the heat exchanger or the furnace it is in because your familys health and safety is far too important to make guesses and assumptions about how dangerous this crack may or may not be. Most furnaces will have a blower delay to get the furnace up to temperature before moving air over the exchanger. More commonly, the cause of a cracked heat exchanger is misapplication or poor maintenance of the furnace. A normally operating gas furnace has a steady blue flame. The shape of the coils depends on the type or model of your furnace. If someone informs you that your heat exchanger is cracked, call the tedder company, and one of our specially trained technicians will immediately assess your furnaces situation.
For this reason, i want to share with you some of the common symptoms and causes of a cracked heat exchanger in a furnace. Dec 02, 2015 diagnosis of a heat exchanger crack typically starts with a no heat service call. My concern is the fact that mechanics walk past other potential carbon monoxide poisoning issues to get to heat exchanger inspection. It is important to repair your furnace if you notice a crack in it. Danger of a furnace with a cracked heat exchanger servicemax. The hot combustion gas in the heat exchanger heats up the metal walls. A cracked heat exchanger in a gas furnace is a serious safety issue. If a heat exchanger becomes cracked, then your heating system will not perform as it should. If the heat ex changer is cracked, air is forced into the combustionchamber. A good furnace tuneup will involve checking your ductwork, as well as the performance and efficiency of the hvac system, which will help you avoid the multiple scenarios that lead to a crack in the heat exchanger in the first place.
If you are inspecting your heat exchanger for cracks, check the bends or weld areas first. The unfortunate part of having a cracked heat exchanger is, well, there is usually no positive outcome for the homeowner. This achr news article explains what to look for when inspecting a furnace flue. When a furnace has a cracked heat exchanger, can it be. Combustion gases leaking from a cracked heat exchanger can cause frequent headaches as well as flulike symptoms. If you find that your furnace heat exchanger has trouble getting enough heat and power, then you may find that it has developed a crack or hole. A cracked heat exchanger is not a problem that should be taken lightly. If we assume the average heating cycle is 15 minutes long, that heat exchanger is heating up and cooling down over 3,000 times per year. This article is about ways to determine if a gas furnace has a cracked heat exchanger. A cracked heat exchanger allows air from the furnace blower to interfere with the flame causing it to flutter or even roll out. Can you repair a cracked heat exchanger on a gas furnace. Oct 14, 2016 this one is about a crack i found in a heat exchanger that caused no symptoms. Were you recently told that your furnace heat exchanger is cracked and needs to be replaced.
Dec 28, 2016 a furnaces heat exchanger uses some type of fuelair mix to burn inside of it, creating heat and getting very hot. Bobs answer to whether or not a cracked heat exchanger can be dangerous is unambiguous. Depending on where the crack is, the supply fan creates a positive pressure on the outside of the heat exchanger that can blow air inside the heat exchanger and on to the flame. Jan, 2020 having a cracked heat exchanger can have a very adverse effect on the overall performance of your home heating equipment. This is a requirement, is part of the fuel gas codes and is ultimately not negotiable.
A cracked heat exchanger can not be repaired either the part or entire unit must be replaced. Heres why your furnace heat exchanger cracked in carbon monoxide testing, central heating and air conditioning, furnace repair. Some cracks have been known to only open when the unit is fired and the heat exchanger metal is hot. Because it allows the exhaust fumes inside the exchanger to leak into the air. The american gas association has even put this in writing they say any visible crack or hole is reason for requiring replacement of the heat exchanger or furnace. These are the weak areas most likely to break first. What are the causes of a cracked heat exchanger in a gas. The air passes over absorbing heat off the surface conditioning it to warm air. How to tell if furnace heat exchanger is cracked 1. Combustible gas increases in temperature and collects in the heat exchanger, allowing it to increase the temperature of the air. Visually check heat exchanger for cracks you will find most cracks form near the back and where the heat exchanger metal bends, since this is where it will be weakest due manufacturer weakening the metal by bending. Here are a few of the reasons you will need to get repairs for a cracked furnace heat exchanger. A furnace lasts between 15 and 20 years over that time, the metal on the heat.
A gas furnaces heat exchanger is the furnace component that actually heats the air. Because the metal of the heat exchanger expands and then contracts as it heats and cools, the stress may eventually cause a crack to form on the exchanger. When your furnace is being inspected, the inspector will be looking for signs of problems with the furnace. Oct 30, 2019 invest in furnace maintenance to avoid heat exchanger problems. The danger of cracked heat exchangers in gas furnaces. A look at a heat exchanger crack that cant be found youtube. Natural gas or propane is being burned and the byproduct of that process is energy in the form of heat, along with water vapor h2o, carbon dioxide co2, carbon monoxide co, carbon or soot.
Should i replace my heat exchanger or buy a new furnace. Its only going to get worse, not betterthe only question is when. A warning about cracked heat exchangers in gas furnace. Where we live, furnaces see nearly 900 hours of use every winter. Signs the heat exchanger in your home furnace is cracked. Is the crack deep enough to leach carbon monoxide co. What are the causes of a cracked heat exchanger in a gas furnace.
Aug 31, 2015 this video is about the your heat exchanger is cracked so your furnace must be replaced scam. The cause of cracked heat exchangers avoid this common scam. The your heat exchanger is cracked so your furnace must be. This video is part of the heating and cooling series of training videos made to accompany my websites. One of the oldest ways to check for heat exchanger cracks is to simply observe the flame when the blower starts. How to prevent a heat exchanger crack in your furnace. If its older than 10 to 12 years old, you may want to go with replacing the entire furnace. The combustible gas will become hotter as it accumulates in the exchanger. Beware of an unethical technician who finds a crack with a camera on a furnace that seems to be running just fine.
Reasons to get repairs for a cracked furnace heat exchanger. The heat exchanger on a furnace is the section that keeps the combustion chamber and the breathing air separate 3. A furnace with a cracked heat exchanger is usually an exception, because of the cost of the repair. For carbon monoxide to leak from a cracked heat exchanger, two things need to be happening. If we discover that a customers furnace has a cracked heat exchanger, we shut the furnace off at the electrical switch and gas valve and tag the appliance for repair.
One of the best ways you can protect your home from the dangers of a cracked heat exchanger is. Cracked heat exchanger deciding to repair or replace depending on the age of your furnace, a cracked heat exchange probably means you need a new system. The heat of the combustion gas raises the temperature of the metal, and as the air from the blower passes around it, heat transfers to it. Located in the center of the furnace, it is where fire, gas and heat connect. This procedure is as simple as watching the flame and observing if it the flame moves or changes when the blower starts.
One of the most common reasons a gas furnace can be taken out of service, is when the repair technician finds to a cracked heat exchanger. The service technician has the time, experience, or even reason to suspect the exchanger is cracked. A heat exchanger is made of thin metal, and as it heats up from the combustion of the furnace, it transfers the heat to the air being distributed through the house by the blower 3. Inside of your furnace or boiler there is actually a fire burning. Guide to furnace heat exchanger inspection, testing, leaks how to inspect and test furnace heat exchangers for leaks photographs show clues indicating leaky, dangerous furnace heat exchangers furnace heat exchanger leak testing, a complete list of methods used to find or test for leaks in a furnace heat exchange what is the allowable amount of gas fired heat exchanger leakage. Cracked heat exchanger furnace trouble shooting help. Broken and leaking heat exchangers are responsible for about 1,500 deaths per year in the united states, and many more people are poisoned by exposure to toxic gasses that go unfiltered by defective heat exchangers. It is recommended that you have your furnace inspected yearly, preferablly before cold weather hits. Heat exchanger cracks are a serious furnace repair issue. This one is about a crack i found in a heat exchanger that caused no.
This can cause a fire or burned wiring and should trip the roll out switches, which are temperature sensors located near the front and above the burners. There are certain signs to look for to determine if the heat exchanger has been. And please remember never try to run a furnace when your heat exchanger is cracked. Not only is furnace performance an issue, but heat exchanger malfunctions can pose serious health and fire risks. Towards the bottom of the page on thecomyths web site, youll find this text. Most repairs require a component that will return the furnace to normal and safe operation. If you have a heat exchanger crack, you need to replace the heat exchanger or the furnace. The reason a crack in a heat exchanger is such a cause for concernand reason to think about replacing a furnace is because it creates a major health hazard. Not having proper maintenance performed by a skilled professional will also take years off the life of a heat exchanger. This trips a safety switch and shuts down the furnace. Dangerous cracked heat exchangers in furnaces carbon monoxide detectors and cracked heat exchangers. When faced with that decision, something to consider is the age of your unit. A crack in your heat exchanger is no trivial matter. A heat exchanger crack is one of the biggest safety issues that your furnace can develop.
Often when cracks are present in a heat exchanger, soot from the combustion process will seep through and discolor the metal. The american gas association has even put this in writing. The heat exchanger is a set of coils or tubes typically located above the blower and below the plenum, where the pilot light starts. If there is a crack in the furnaces heat exchanger, there will be some signs and symptoms that are normally evident concerning the furnace. Cracked heat exchanger furnance repair in anderson township. The heat exchanger is a key part of the furnace and is responsible for the actual heating of air. Cracked heat exchanger deciding to repair or replace. The heat exchanger on a furnace is the section that keeps the combustion chamber and the breathing air separate. Hvac businesses in minnesota lock out furnaces when cracked heat exchangers are found. Unless you are one of the top 3% of people who have all the money, replacing the furnace is going to hurt the pocket book if you have not planed for it, but it has to be done. Older furnaces can develop major issues, such as a cracked heat exchanger.
This effect will get worst as the furnace heats up from expansion and the crack gets bigger. Carbon monoxide can seep out of through a cracked heat exchanger. Heres why your furnace heat exchanger cracked heating. Be on the watch for symptoms of a cracked heat exchanger like. Any verifiable crack requires replacement of the heat exchanger or furnace. A furnace lasts between 15 and 20 years over that time, the metal on the heat exchanger heats up and expands, and then contracts as it cools. Most newer models are equipped with special safety features that keep risks down. The most likely cause for a crack in the heat exchanger is corrosion. The problem with finding a crack in a furnace heat exchanger is that you can see very little of the heat exchanger without disassembling the furnace. Needless to say, visual heat exchanger analysis provides woefully inadequate answers to these very important questions. In a normal gas furnace, the flame will usually appear blue. Combustion pollutants, such as carbon monoxide, nitrogen dioxide and sulfur dioxide, can cause eye and nose irritation, disorientation, sleepiness and nausea. Corrosion because of reaction between the combustion gas and the metal often because of improper venting can also weaken the metal to the point where cracks.