Blower Running Constant

Old 08-20-19, 08:12 AM
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Blower Running Constant

We had a recent lightning storm pass and nearby ground strikes damaged several electronics in my home. Here are some details I'm hoping to resolve:
  • Problem: blower runs constant, regardless of settings at the thermostat
  • Lennox residential system - approx. 16 months old
  • Single unit, zoned in a 2-story home (upstairs + downstairs)
  • Replaced the zone board (HZ311)
  • Should I:
    • Replace the capacitor on the ECM motor (attached: 100600-02)
    • Replace the transformer (attached: 42J3201)
  • Do you suggest I troubleshoot anything else? (ie: control board in the air handler)
Thank you, in advance, for any assistance/recommendations!

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Old 08-20-19, 07:26 PM
Tolyn Ironhand's Avatar
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Replace the capacitor on the ECM motor (attached: 100600-02)

Replace the transformer (attached: 42J3201)
Only if it is not putting out 24 volts (aprox)

If you disconnect the thermostat red wires at the furnace does it stop?
Old 08-20-19, 07:40 PM
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Test for a call for the blower with your meter.
It’s likely either the thermostat or control board. A quick test with a meter will show what’s going on.
The parts you pictured have no effect on your problem.

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