That is a defrost cycle and it is normal. The unit reverses briefly to melt frost off the outdoor coil. What is not normal is a solid casing of ice that never clears – that is a defrost control problem.

You can handle this one yourself. No call needed.

Related

• Ductwork threaded through a house built for floor grates
• One central return for the whole house
• Water heater vents into the chimney and the furnace no longer does
• Silver-wrapped tape on old duct joints
• Additions still on window units
• Uninsulated walls and an oversized condenser
• Furnace runs but the house never warms evenly
• Electrical panel cannot support a modern condenser

Back to Hvac.

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Written by Jaylan Jones. I Like To Fix earns a referral fee when a call connects to a contractor. See our business-model disclosure.