Service & Troubleshooting第 85 / 110 题
A dirty flame sensor on a modern furnace most commonly causes what symptom?
a.Continuous cooling
b.The burners light then shut off after a few seconds (flame loss)
c.High head pressure
d.Frozen evaporator
解析
A flame sensor confirms flame is present; when it is coated with oxide it cannot conduct the flame-rectification signal, so the control shuts off the gas as a safety response. Cleaning the sensor typically restores operation. This is a very common no-heat service call.
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