Repair or replace

Age is the first thing to look at. ENERGY STAR lists a heat pump or air conditioner more than 10 years old as a reason to consider replacing it. For a furnace or boiler, the mark is more than 15 years old. Equipment under 10 years old, or under 15 for a furnace or boiler, falls on the repair side of its list. If two or more items in its replace column apply to you, it is probably time to consider an ENERGY STAR replacement.

Age alone does not settle it. If your equipment is more than 10 years old or not keeping your house comfortable, the EPA recommends having a professional HVAC contractor evaluate it. Regular maintenance can cut heating and cooling costs by 10% or more and will extend the equipment's life.

Source: ENERGY STAR · U.S. EPA · U.S. Department of Energy

How the system behaves matters as much as its age. ENERGY STAR lists equipment that needs frequent repairs while your energy bills go up, since your heating or cooling equipment may have become less efficient. It also lists rooms that are too hot or too cold, though improper equipment operation, duct problems or poor insulation could be the cause. Humidity problems, excess dust or rooms that never seem comfortable are on the list too, and poorly insulated ducts could also be behind them.

Some of these signs point to the ducts or the house rather than the equipment. Leaky ducts waste energy and can reduce airflow and comfort. In most cases, equipment shows signs of underperforming well before it needs an emergency replacement. Noticing them early gives you time to compare repair and replacement without the pressure of a breakdown.

Source: ENERGY STAR

If your air conditioner is older, find out which refrigerant it uses. You can no longer buy a central air conditioner that uses HCFC-22, also called R-22, but you can keep servicing your existing one. The EPA does not require homeowners to replace their equipment; since January 1, 2020, no new R-22 is made or imported, but used R-22 cleaned to the same standard as new stays available. The EPA expects reclaimed and earlier-made R-22 to be available well after 2020, but the price and availability may change.

Repairs on these older systems have their own rules. Alternative refrigerants will not work well without changes to system parts, so technicians repairing leaks will most often keep charging R-22. If your air conditioner leaks, the EPA says to ask your technician to find and repair the leak instead of topping it off. Propane and other unapproved refrigerants are a safety hazard in home air conditioners, which are not designed for flammable refrigerants. EPA rules let owners replace a broken R-22 condensing unit, the outdoor part, with a new one, but it must meet regional efficiency standards.

Systems with a newer refrigerant face a similar choice. A homeowner can replace a faulty part, such as a condensing unit or indoor coil, with a similar R-410A part. The EPA lists availability of parts, energy efficiency and total maintenance costs as factors when weighing a repair against a new system with a lower-impact refrigerant.

Source: U.S. EPA

Efficiency has improved, and that changes the math on an old system. Installed correctly, high-efficiency units can save up to 20 percent on heating and cooling costs. An ENERGY STAR furnace is 15% more efficient than a conventional furnace. An ENERGY STAR boiler is 5% more efficient than a new, standard model. A furnace's AFUE rating measures how much of the fuel's heat actually reaches your house.

A more efficient product pays off when its lifetime energy savings are larger than any extra up-front cost. Ducted heat pumps use your home's existing ductwork to heat and cool. In most homes, depending on factors like the climate zone, they can go in as a drop-in replacement for a central air conditioner or furnace. The heat pump pages explain how they work in a Chicago winter.

Source: ENERGY STAR · U.S. Department of Energy

A replacement should not simply match the old unit's size. Your contractor can find the right size using ACCA Manual J or an equivalent sizing calculation. Rules of thumb are too often used to size systems, which leads to systems that are far too large. It can be tempting to skip the load calculation for a replacement where the size of the existing equipment is known. ACCA says a proper Manual J load calculation is required by national building codes and most state and local jurisdictions.

Too big is not better. Oversized equipment may cycle too often, giving less comfort and a shorter life. Oversized equipment will not run long enough to remove humidity from the air. The sizing page explains how a load calculation works.

Source: ENERGY STAR · U.S. Department of Energy · ACCA

A few questions make the choice clearer. Ask whether the contractor will size the new system with ACCA Manual J or an equivalent calculation. For an air conditioner or heat pump, ask whether the technicians are EPA-certified to handle refrigerants. If the problem is a refrigerant leak, ask whether the leak can be found and repaired. Whichever way you go, ENERGY STAR says to make sure a professional contractor does the complete job.

Getting rid of old equipment has rules too. The Clean Air Act requires refrigerant to be recovered from appliances before final disposal. Older appliances may also contain mercury, contaminated oils or PCBs, which are hazardous substances. Ask how the old unit will be removed and where it will go.

Source: ENERGY STAR · U.S. EPA · U.S. Department of Energy