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Rick, HVAC Supervisor
Category: HVAC
Satisfied Customers: 21356
Experience:  40+ yrs. experience as a licensed oil & gas technician.
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My problem is very similar to the f4 problem presented on my

Customer Question

my problem is very similar to the f4 problem presented on my screen. My only addition would be that when the reset works just befor it runs normally there is a noise (loudish) and the unit shakes a little like some blockage came free and then settles down into normal operation.
Submitted: 1 year ago.
Category: HVAC
Expert:  Rick replied 1 year ago.

Welcome to Just Answer, my name is ***** ***** I will do my best to help you with your issue. If my initial response doesn’t answer your question then let me know and we can continue our conversation.

That "loudish noise" is likely delayed ignition which indicates this unit needs professional service asap.

Customer: replied 1 year ago.
the spark is sparking. and I cleaned the plastic U trap out. the unit is 3 years old and there was a fair bit of soot in it
Expert:  Rick replied 1 year ago.

Soot is another indication the unit needs professional service. This unit should never make soot.

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