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Dangerous conditions in gas furnaces
Heat exchanger problems
A heat exchanger is a metal separation between the burning gasses and air (or water) passing thru the furnace. On hot air furnaces, the separation is made of sheet metal. The thickness is about 20 gauge.
Because the heat exchanger is exposed to high temperatures, fatigue cracks can occur. Also if the furnace is overfired, the heat exchanger can be burned out. If it is underfired, water can condense in the heat exchanger and rust out can occur.
Because the heat exchanger is exposed to high temperatures, fatigue cracks can occur. Also if the furnace is overfired, the heat exchanger can be burned out. If it is underfired, water can condense in the heat exchanger and rust out can occur.
Heat exchanger failures click here
Flame problems
The furnace below uses an electronic ignition that starts by turning on gas to the pilot light and also starts a spark to light the pilot. When the pilot lights, there is a proving system that insures that the pilot has lit. Then it allows main gas to come on.
In this case, the main gas valve is stuck on so when the pilot valve opens, so does the main gas. This is dangerous because if the spark fails, the unburned gas will be dumped into the furnace and could cause an explosion.
The video below explains what has happened.
In this case, the main gas valve is stuck on so when the pilot valve opens, so does the main gas. This is dangerous because if the spark fails, the unburned gas will be dumped into the furnace and could cause an explosion.
The video below explains what has happened.
Anytime there is a flame, there is a possibility of carbon monoxide as a product of combustion.
Because it is a poisonous gas, we must be concerned about keeping it out of the air we breathe inside a structure.
The largest potential source of CO in the home is the fuel burning furnace.
To determine if the furnace is allowing CO into the home, we use a CO detector to test. The video below shows how this is done.
Because it is a poisonous gas, we must be concerned about keeping it out of the air we breathe inside a structure.
The largest potential source of CO in the home is the fuel burning furnace.
To determine if the furnace is allowing CO into the home, we use a CO detector to test. The video below shows how this is done.