Frequently asked questions

Once a year each, timed to the season: the furnace in early fall before the first cold snap, the air conditioner in spring before the first humid stretch. With about 5,645 heating degree days a year, the furnace does most of the work and the fall visit is the more important of the two. A service visit means measurements and cleaning, not just a visual once-over: combustion readings, temperature rise, static pressure, refrigerant pressures, capacitor values, coil and drain condition. If a visit does not produce numbers, it was not a service.

The filter the system's static pressure can tolerate. In a lot of older Miami Valley houses with undersized returns, a dense high-MERV one-inch pleated filter chokes airflow and causes the exact problems it is meant to prevent: frozen coils in summer, limit trips in winter, and blower motors that run hot. A moderate-MERV pleated filter changed every one to three months is the usual right answer, and if the house can be fitted with a thicker four- or five-inch media cabinet, that is the best upgrade for both airflow and filtration. The technician can measure whether your return can handle a denser filter.

A Manual J load calculation measures the house: square footage by room, ceiling heights, wall and attic insulation, window sizes and types, orientation, air leakage, and the local design temperatures. The output is the heating and cooling capacity the house needs today. Without it, equipment gets sized off the old unit's label or a square-foot rule of thumb, and in this region that almost always means oversized. Oversized equipment short-cycles, runs loud, wears out faster and, in summer, leaves the house humid. The calculation takes some time on the estimate visit, and it is the only honest basis for a size.

Physics and ductwork. Warm air rises, so the upstairs gains heat all summer and the downstairs loses it all winter. Most Dayton-area two-story houses were ducted for heating from a basement furnace, which means plenty of supply to the first floor, less to the second, and often no return air upstairs at all. Fixes range from cheap to structural: adjusting dampers seasonally, running the fan continuously, a two-stage or variable-speed system for longer mixing cycles, adding an upstairs return, zoning dampers, or a ductless head for the second floor. A bigger air conditioner is almost never the answer.

Not more than one or two, and not in a house that already has airflow problems. Closing supply registers raises static pressure across the whole duct system, which pushes more air through leaks, strains the blower, and can cause the coil to freeze or the furnace to trip its limit. If you want less conditioning in a room, a partially closed register is fine; sealing off a third of the house is not.

An 80 percent (mid-efficiency) furnace sends about a fifth of the heat it makes up a metal flue. A 90-plus percent (condensing) furnace pulls that heat out of the exhaust, vents through PVC pipe out a side wall or roof, and drains the resulting condensate. In practice: lower gas use over a long Ohio heating season, a different venting route, a condensate drain to manage, and usually a quieter, more even heat because most condensing furnaces are two-stage or modulating. The install cost is higher and the venting change can affect a water heater that shared the old chimney. The estimate lays both out.

Look for the load calculation result and the equipment capacity it led to; if a quote has no calculation, ask why. Check that the indoor coil and outdoor unit are listed as a matched pair with model numbers. Look for the venting plan, the condensate plan, the electrical work, the permit, and whether duct corrections are included or excluded. Then compare startup commissioning: does the installer commit to recording gas pressure, temperature rise, static pressure, refrigerant charge and combustion readings? Two quotes for the 'same' furnace can differ a lot on what is actually being installed around it.

For a small, accessible leak or an electrical part, yes. For a coil or compressor failure, usually not. R-22 production and import ended in the United States in 2020, and what remains is reclaimed stock at high prices. A system old enough to use R-22 is also old enough that the next failure is not far off. You will get the repair number and the replacement number and can decide with both in hand.

Have working CO alarms on every level, including near the sleeping areas and within earshot of the furnace, and replace them when they reach the end of their rated life, usually seven to ten years. Have the furnace's heat exchanger and venting inspected every year, and the water heater's venting with it. Never run a generator, grill or gas space heater indoors. If an alarm sounds, leave the house and call 911 or the gas utility from outside. Most of the gas-heated homes in Dayton are older houses with shared chimneys, and venting problems are as common a CO source as cracked exchangers.

It helps when it is set up for the equipment. Schedules and setbacks save some gas in a long heating season, and remote alerts catch a failed furnace before the pipes freeze. It hurts when it is wired wrong for a heat pump or dual-fuel system, or when a homeowner sets aggressive setbacks that make a heat pump run its resistance strips every morning. If a thermostat is part of an installation, it is configured and tested for the system it controls, and you are shown how it is set.

The refrigerant in the old air conditioner is recovered into a cylinder, as federal rules require, not vented. The equipment is hauled away and the metal is recycled. If the old furnace shared a chimney with the water heater, the chimney is evaluated and, where needed, relined so the water heater vents safely on its own. None of that should be left to the homeowner to sort out, and it is part of the quote.

The two seasonal visits described above can be set up on a recurring basis so they are not forgotten. The details, what each visit includes and what it costs, are explained plainly when you ask, and there is no requirement to be on a plan to get service or a fair repair price.