INDIANAPOLIS GUIDE

Repair the part, or replace the system

The outdoor unit cooled the house for a week, then the upstairs went warm again, and now someone is talking about a new system while the old one is still humming. That conversation belongs on paper, not in a hurry at the curb. Repair and replacement answer different questions. A repair puts a failed part back in service. A replacement changes the equipment, and sometimes the ducts, the thermostat, and the permit path. Neither choice is a slogan about age. Start with what failed, whether the rest of the system is sound, and whether the house is safe to stay in tonight.

By Mike Maziarz · Sources checked October 6, 2026 · How we write these guides

Name the failed part before the whole system

Ask what stopped working. A capacitor, an igniter, a blower motor, a thermostat, a condensate pump, and a cracked heat exchanger are not one decision. The first four can be repairs. The heat exchanger is a safety conversation. Write the part name in your own words and keep the data-plate photo with it.

Then ask what was tested and found sound. An outdoor unit that still runs, ducts that move air, and a furnace heat exchanger that was inspected and left in place are reasons a repair can be the whole job. A quote that replaces everything because one part failed should say why the other pieces cannot stay.

Age on the data plate is a fact, not a countdown. Read the year and write it down. Do not let a round number of years decide by itself. A young unit with a damaged coil can be a worse candidate for repair than an older unit with a single failed motor. The history of this machine matters more than a chart.

Safety can end the repair option

A heat exchanger that is cracked, rusted through, or flagged by a combustion test is not a part you patch with tape. Combustion gases belong in the vent, not in the supply air. If a technician stops the furnace for that reason, leave it off. Ask for the finding in writing. Do not ask someone else to bypass the switch so the house can have heat for the weekend.

A carbon monoxide alarm, or headache and dizziness that ease outdoors, is not a repair-versus-replace meeting. Get everyone outside and call emergency services. The carbon monoxide page is the sequence. After the house is cleared, the equipment decision can wait on the sidewalk, not in the basement.

A gas smell is the same kind of stop. Leave, do not flip switches, and from outside use the emergency number on the gas bill. Many Indianapolis addresses are on Citizens Energy Group, and the number is the one printed for your account. Ignition trouble after the utility clears the building is covered in the furnace guide. Do not fold a leak into a replacement pitch and keep the family inside.

Repeated failures and a system that will not stay fixed

One repair does not mean the equipment is done. A second and third repair on the same unit in a short stretch is a pattern worth laying on the table. Ask whether the failures are related. A flame sensor this month and an igniter next month can both be symptoms of a dirty burner, or they can be bad luck. The technician should say which story the parts support.

A cooling system that is low on refrigerant again after a recent charge is a leak until someone shows you otherwise. Recharging without a repair is not a replacement plan and it is not a lasting repair. Ask where the refrigerant went. If the coil is failing and the outdoor unit is also near the end of its service, that is when replacement of the pair becomes a coherent sentence. It still does not require a dollar figure to understand.

Keep the invoices. The pattern is invisible if every visit lives on a different scrap of paper. Dates, part names, and whether the symptom returned are the record for the next conversation.

The rest of the house has to fit

Replacing an outdoor unit and leaving a mismatched indoor coil is a technical choice, not a slogan. Ask whether the indoor and outdoor pieces are meant to work together, and what happens to the line set and the thermostat. In a basement house the furnace may stay and only the cooling half may change. In a closet or attic, the air handler may be the piece that is hard to reach, which changes the work even when the decision is the same.

Ducts are part of the fit. New equipment on crushed, disconnected, or undersized ducts will not feel like a new system. Ask for a look at the returns and the main trunks, especially where an older house in Fountain Square, Irvington, or Broad Ripple has an addition. You want a description of airflow, not a promise that every room will match.

Electrical capacity matters for a heat pump or electric backup. If the proposal adds load, ask who checks the panel. That is a scope item. It is also a reason not to buy equipment from a flyer and hope the existing wires are enough.

A change-out is a different kind of paperwork

Repairing a part in place and setting new equipment are not the same errand at the permit counter. Indianapolis building permits are handled by the city. If the house is in Carmel, Fishers, Greenwood, Noblesville, Speedway, or another jurisdiction, that place has its own counter. Ask the company which office applies to the job address and who pulls the permit. Do not treat a neighboring city's habit as if it covered Marion County, or the other way around.

A permit is not a review of the sales pitch. It is a check that the work, as described, meets the rules that office enforces. Ask what will be inspected and whether you need to be home. Keep the permit record with the invoice and the warranty papers.

Rules change and this page will not quote an ordinance number. If a company cites a code section as the reason you must replace a unit, ask them to show you the requirement and then confirm it with the office that covers the house. Your job is to hear a specific rule, not to accept a vibe.

Do not make the call while the house is getting cold

If the indoor temperature is falling on a winter night, the decision in front of you is heat for tonight, not a full equipment plan. Emergency heat on a heat pump, a space heater used as the manufacturer intends, and a closed-off room are temporary. The no-heat checklist is the overnight page. Sign a replacement later if the finding still supports it, when you can read the paper.

Some steps are never the bridge between tonight and a new system. Do not jump a safety switch, do not add refrigerant, and do not take the furnace door off to force it to run. The do-it-yourself boundary is there so a cold night does not turn into a bypassed control.

Ask for two written options when you are calm: repair of the named part, and replacement with a list of what is included. Compare the findings, the warranties in words, the permit, and what is left behind. Leave payback math off this page. If a company will not describe the work without a countdown, that is information about the company.