23
Easy Fix
Carrier · Central Air Conditioners & Furnaces
Pressure Switch Did Not Close
Quick Answer
Error code 23 on your Carrier Central Air Conditioners & Furnaces means: Pressure Switch Did Not Close. This is usually fixable — see the step-by-step guide below.
Likely Causes
How to Fix It
1
Inspect flue pipe and intake for blockages such as bird nests, ice, or debris
2
Check pressure switch hose for cracks, kinks, or disconnections
3
Verify inducer motor is running and creating proper draft
4
Check condensate drain line for clogs and clear if necessary
5
Test pressure switch with a manometer to verify it closes at the correct pressure differential
Pro Tip
This is a common issue that most users can resolve without specialized tools. Try the first step before moving on to more complex solutions.
Parts You May Need
Pressure switch
Pressure switch tubing
Inducer motor assembly
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