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Troubleshooting A Gas Furnace Water Leak

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Unplanned-for water leaks in a home can be quite damaging. They can ruin your hardwood flooring, increase incidences of mold attacks in your home, create ugly marks on your walls and even cause rotting of wooden parts of the support beams of your house. One of the most common unplanned-for leaks in a home is a gas furnace water leak. Here is what you should know about the likely cause of your furnace water leak problems.

Condensate drainage problems

Condensate drainage problems are a common cause of water leaks in high efficiency furnaces. Therefore, the first step you should take is to determine whether your furnace falls into the high efficiency category.

An easy way to do this is to take a look at the furnace's exhaust. If it is made of plastic, your furnace is a high efficiency furnace and condensate drainage problems are likely to blame for your water leak problems. This is because these types of furnaces usually have two heat exchangers. As a result, the cooling effect that these furnaces have with warm air is usually enough to trigger condensation.

Problems that can cause water leaks includes the clogging of the drain pipes, worn-out condensate pan or a backed-up or clogged drain. When any of these conditions arise, they usually reduce the ability of the condensate drainage system to guide the condensate away from the furnace, something that then leads to furnace gas water leaks.

To prevent condensate-related water leaks, unclogging the drainage system is a must. As for worn-out pipes and pans, replacing them is the only way to prevent further furnace water leaks.

Humidifier-related problems

During cold months, the amount of humidity in a home can reduce to levels that can cause discomfort. To help make homes comfortable, manufacturers sometimes install a dehumidifier that supplies water to the furnace. What happens is that the humidifier pipes the water to an evaporator pan and once in the pan, the water is converted into a gas and then mixed with the warm air being supplied into the home. If the evaporator pan has a tear or a hole, a water leak will occur. This can also happen if the piping supplying the water is faulty. Also, there are times where as a result of poor installation, the cold water being supplied to the evaporator pan will trigger condensation that will then cause water leaks.

In such cases, replacing the faulty parts of the furnace's humidifier system will help to minimize this type of water leak.

Improper exhaust pipe sizing problems

This is a problem that is common in both medium efficiency and standard efficiency gas furnaces. Why? Because these furnaces usually use metallic exhaust pipes. When these pipes are properly sized, the amount of heat loss that occurs in this area is rarely enough to cause condensation to occur. However, if the pipe is improperly sized, the amount of heat loss that occurs may sometimes be enough to force moisture in the exhaust to condense. This moisture then drips back into the furnace, causing the water leaks. Replacing the improperly sized piping should be enough to solve your water leak problem.

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