Carbon Monoxide Alarm and an Unpermitted Ductless Split in an Apartment
A complaint inspection at a 12-unit apartment building finds a carbon monoxide alarm in unit 2 reading 65 ppm. In the basement, a 300,000 Btu/h atmospheric boiler is connected to a 6-inch masonry chimney with spalling mortar and visible spillage at the draft hood. A new 400 cfm clothes dryer exhaust was installed in the adjacent laundry room without make-up air. The building owner says the boiler was cleaned last year and the chimney is original. In a former storage room, a 2-ton ductless split has been installed without a mechanical permit. The indoor unit drains through a flexible tube that crosses a walkway to a floor drain. The line set is 40 feet long, and there is no disconnect within sight of the outdoor unit. The owner says a handyman did the work last month and asks the inspector to approve it so the unit can be rented. No plans or load calculation were submitted, and the outdoor unit is mounted on brackets above a public walkway.
1. What immediate action do you take for the carbon monoxide condition, and why?
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A 65 ppm reading is an emergency condition, not a routine correction. I would have the occupants leave the affected unit, ventilate the space, and notify the gas utility and fire authority according to local procedure. I would shut down the boiler or red-tag it as an unsafe condition, because visible spillage at the draft hood plus a deteriorated masonry chimney is a credible source of combustion products. I would not rely on the alarm reading alone; I would use a combustion analyzer and draft gauge to document spillage, but I would not delay evacuation to complete testing. The new 400 cfm dryer exhaust is a likely contributing cause because it can depressurize the basement and reverse the chimney draft. I would document the alarm reading, the spillage, the chimney condition, and the exhaust installation, and I would require the boiler and venting to be repaired and tested before reoccupancy. Any reoccupancy should be conditioned on a draft test with the dryer and other exhaust fans operating.
2. What enforcement options apply to the unpermitted ductless split and the handyman installation?
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The ductless split is unpermitted work, and the lack of a permit is not cured by the owner's request for approval after the fact. I would issue a notice of violation and a stop-work notice for the mechanical work until a permit is obtained. The permit application would require a load calculation, equipment listing and installation instructions, line-set length and charging information, condensate disposal, electrical disconnect, and structural support for the brackets. The 40-foot line set may exceed the manufacturer's maximum length or require additional charge; that must be documented. The condensate tube crossing a walkway is both a code and a safety problem, and the missing disconnect within sight is an electrical defect. If local law requires a licensed contractor for this work, the owner must use one; the handyman's status should be referred to the licensing authority. The owner is entitled to written notice and an appeal, but the rental approval cannot be used as leverage to waive the permit and inspection requirements.
3. Outline the approval path and the inspections you would require before the unit can be occupied.
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For the CO condition, the path is correction first: repair or reline the chimney, correct the boiler venting and combustion air, and address the dryer exhaust with make-up air or a listed arrangement. Then provide a draft test and combustion analysis with all exhaust fans operating, and obtain clearance from the gas utility or fire authority if they responded. For the ductless split, require a permit, a load calculation, and a plan showing the outdoor unit support, line-set route, condensate disposal, and disconnect. Inspect the brackets and fasteners, the penetration flashing, the line-set protection, the condensate trap and termination, the electrical disconnect, and the refrigerant charge documentation. Verify that the outdoor unit is not discharging onto a walkway or blocking egress. After corrections, perform a final inspection and document the results. I would not approve occupancy on the basis of the owner's assurance or the handyman's workmanship; each system needs its own inspection and test record.