Heating & Cooling Inspection: Furnace, Boiler and AC

Furnace and boiler inspection

Older or poorly maintained furnaces and boilers are among the most common big-ticket surprises after a closing. We look at how the equipment operates, the condition of accessible components, and venting — including whether a water heater was left on an oversized chimney after a furnace replacement.

If we see signs of a compromised heat exchanger or a venting problem, we say so plainly: the equipment should stay off until a qualified technician evaluates the safe repair or replacement options.

Before winter travel: inspect the heat that protects the plumbing

Before leaving a Chicago-area home in cold weather, consider what happens if the heat stops while nobody is there. Water lines near an outside wall or in an unheated space may be exposed even when the main rooms feel comfortable. The American Red Cross recommends leaving the heat on during winter absences. An equipment inspection helps identify concerns before departure, but it is not a substitute for a plan to notice and respond to a failure.

Tell the inspector when you will be away, whether anyone will occupy the building and which rooms have been difficult to heat. Arrange for a trusted person to check the house, with access and a clear way to reach you. Decide who can arrange service if temperatures fall or power fails. A temperature alarm can help, but its usefulness depends on sensor placement, power, batteries, connectivity and someone actually receiving and acting on the notification. Do not treat an app reading as proof that every pipe is protected.

For a qualified professional, the review can include observing accessible furnace or boiler cycling, thermostat response and controls, heat delivery and airflow, visible vent connections and ground-accessible vent terminals. On condensing equipment, visible condensate piping and signs of leakage or poor drainage deserve attention. Describe short cycling, unusual shutdowns or rooms that never warm up; observations help direct the evaluation without requiring you to open equipment, alter wiring or reset safety controls.

Agree on the inspection scope before the visit. Looking at accessible components and observing an operating cycle is different from disassembly, instrumented combustion testing or a separate fault diagnosis. Those procedures are not promised in every inspection. The report should identify what was possible under the conditions that day and what needs another visit or a specialist. Cooling equipment should not be forced to run in unsuitable cold conditions just to complete a checklist.

If the building is already losing heat, arrange repair first rather than relying on a future inspection to resolve the active problem. Once repairs are complete, confirm who will recheck operation before you leave. Domestic water winterization is a separate decision: maintaining an occupied, heated home differs from properly shutting down an unoccupied property. Do not drain a heating boiler or make system changes on the assumption that all water systems can be winterized the same way.

For domestic water protection and the occupied-home versus shutdown distinction, see how to winterize your plumbing system.

For heat that has already failed, request no-heat repair; an inspection is not a repair appointment.

For broader upgrade or project planning, see heating and cooling consulting.

What the inspection report should make clear

A useful report distinguishes accessible observations from conclusions that require further testing. It should describe the operating conditions during the visit, the equipment that could be reached, tests actually performed and tests not performed. If weather, access or a shutdown prevented evaluation, that limitation matters as much as a photograph of a visible concern. Inspection findings do not establish that every hidden fault has been found, certify efficiency or predict exact remaining life.

Separate urgent follow-up from repairs or upgrades that can be planned. Ask whether an item needs repair, specialist evaluation or a second opinion, and who will recheck it after work is complete. This trade-level review complements a licensed whole-home inspection; it does not replace one. Electrical systems remain outside our inspection scope.

AC inspection

Air conditioning is often inspected in the cold months when it cannot be run safely. We inspect the condenser, the accessible indoor coil area, refrigerant lines and condensate drainage, and note when the system should be tested in warmer weather.

Venting and carbon monoxide concerns

Venting is the part of an HVAC inspection that matters most for safety. We check vent connections, slope, terminations and combustion air for the gas appliances we inspect and flag anything that needs attention. A working carbon monoxide alarm is still essential in any home with gas appliances.