Work Performed: Responded to a low heat call for a 2015 Keeprite single-stage high-efficiency furnace. Client reported that resetting the power temporarily restores heat, but the furnace delays heating after reset. Explained that the Keeprite furnace goes through a 90-second pre-purge cycle after power-up, which is normal operation before ignition. - Performed full diagnostic inspection of the furnace - Found water in inducer-to-pressure-switch tubing, likely causing intermittent pressure switch issues due to partial blockage in condensate drain - Cleared condensate drain and tubing while performing service - Completed full maintenance including burner cleaning, visual inspection, and combustion test - Verified proper operation of pressure switches and inducer motor - Checked temperature rise, gas pressures, and all electrical connections — all within specifications Results: Drain is now clear, furnace is operating normally, and no further issues found at this time.