If you have a furnace, then leaks are a common issue that you may face every once in a while. It is very frustrating when such crucial equipment of your home HVAC system leaks water. You may wonder what you can do in this situation. Well, sometimes it is easier to call an HVAC technician who is expert in this, but there is no loss knowing the different parts of your furnace and what to do when it doesn’t work.
Furnace Types
To identify the reason causing your furnace to leak, you first need to know which type of furnace you have in the first place. HVAC technicians to know whether you have a high-efficiency or standard/low-efficiency furnace to diagnose the problem better. You can decide it with/in a few simple steps.
If your furnace has a metal exhaust pipe and AFUE (Annual Fuel Utilization Efficiency) rating equal or over 90, then it is a high-efficiency furnace. On the contrary, it is the opposite. Now you know what type of furnace you have.
Different Types of Furnace leaks & how to handle the situations
1. Condensation Leak
High-efficiency furnace: If you have a high-efficiency furnace, then condensation leak is likely to happen. Anyway, it is a common problem faced by general users. This is happening because you may have a break in the condensation line or problem in the pump. It can also happen due to the clogged condensation leak.
Standard/Low-efficiency furnace: Again, if your furnace is a standard or low-efficiency furnace, then you likely to have an incorrect sized exhaust pipe as there is no water involved in this category.
2. Faulty Humidifier
Although, furnace humidifiers are simple tools; it stops working when it has a bad drum motor or burned out solenoid water valve. You can check whether your humidifier is working or not. If you did your annual maintenance regularly, you are not likely to face this problem. But still, while installing the humidifier, if it had leaked by itself, then you should fix it. Those who haven’t serviced or repaired it in a year and facing this issue should fix it immediately. Because delay can cause harm to your electrical circuits and boards.
3. Secondary Heat Exchanger Issue
High-efficiency furnace: It is only possible if you have a high-efficiency furnace. Unfortunately, if you have this problem, I am sorry to say that it is the most expensive one to repair. It is better to replace it altogether rather than repairing it. Because with the repairing cost, you can easily buy another furnace. Because secondary heat exchanger produces carbonic acid (a mixture of leaked water and carbon-di-oxide) which causes damage to the heat exchanger from time to time if not fixed. Produced carbonic acid due to the water leakage can cause severe damage to the whole furnace. That’s why in the worst-case scenario, you will have to replace the entire furnace.
4. Air Conditioner Problem
If you notice, your furnace leaks when your air conditioner is on, then your problem is not in your furnace rather than in your air conditioner or AC. If the drain is clogged you’ll notice the leakage. It is the most common reason that you will see your furnace leak even in the summer. Your air conditioner works as a dehumidifier also. It absorbs the water from the air or you can say moisture, then it drains out of your home via a drain line. If there is a problem in the drain line or it is clogged you will see water leakage.
Action after Noticing Leakage
Before calling a professional, you need to do a few things to save your furnace from more damage. At first, you must turn off your furnace since water can damage your electrical circuits of the furnace and if that happens, it can cause you big bucks for the AC repair and Furnace repair. Then, clean up all the water around your furnace as mentioned earlier, it can cost you a lot to repair, if water damages the sensitive electrical circuits. If you have technical knowledge about furnaces, then you can diagnose the problem and solve it by yourself. But it is recommendable that you consult with an HVAC technician.
Bottom Line
Now, let’s review what we have discussed. Firstly, you have to identify what type of furnace you have. You have to take the decision according to the type of furnace you have. Afterward, you will have to diagnose according to the criteria that were mentioned above. As mentioned, if your secondary heat exchanger is damaged, it is better to replace the whole furnace altogether rather than repairing it. But it is better to consult with a professional technician. For this, you can call an HVAC technician to diagnose the problem repair your furnace.
See the summary in this infographic – Solution to Different Types of Furnace Water Leaks [Infographic]

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