Air conditioners rarely fail on a cool evening. They tend to throw in the towel on the hottest day of the year, right when your family, your pets, and your patience need that steady stream of cool air. After twenty years of crawling through attics, swapping compressors in cramped side yards, and tuning systems through Midwest heat waves, I’ve learned that most breakdowns don’t come out of the blue. They come from little things that were left undone. A filter that stayed in a month too long. A coil that never got a rinse. A thermostat with a dying battery.
Good maintenance is not about superstition or bells and whistles. It’s a repeatable set of habits that keep an AC running at its designed capacity and efficiency, month after month. Do a little at the right time, and you avoid the big bills and the miserable nights. That’s the philosophy we follow at Summers Plumbing Heating & Cooling, and it’s what I want to pass along here.
Why maintenance pays for itself
Cooling systems don’t just lose efficiency, they lose it in layers. Dust and lint load up the filter, which restricts return airflow. Lower airflow means the evaporator runs colder, which invites ice accumulation on humid days. Ice forces the compressor to work harder, drawing more amps and raising operating temperatures, which accelerates wear on windings and bearings. Once you understand the chain reaction, you see why small fixes make a big difference.
On a typical three to four ton residential system, a restricted filter can add 10 to 20 percent to your energy use. A dirty outdoor coil often costs another 5 to 15 percent. Miscalibrated thermostats can swing comfort by two degrees or more, which is roughly a 3 to 6 percent energy shift. None of these require an expensive part to correct. They require attention, a garden hose, and sometimes a screwdriver.
The payoff isn’t only lower bills. A well-maintained system holds a steady indoor humidity, keeps noise down, and avoids short cycling that chews through compressors. For most homes in Indiana, a tuned AC should last 12 to 15 years. With neglect, 8 to 10 is common. The difference is thousands of dollars.
Filters: the five-minute habit that prevents most calls
I can usually tell who changes their filters on time by the sound of their system. A starved blower has a distinct pitch, and it’s not a sound you want. Filters are not set-and-forget. They’re the most affordable insurance you can buy for your AC.
If your filter sits in a return grille, you can handle the swap in minutes. If it lives in a media cabinet by the furnace, it’s still simple once you’ve done it once. Keep a felt-tip marker near the cabinet, write the change date on the frame, and set a phone reminder for the next interval. In homes with pets, smokers, or active remodels, cut the schedule in half. When in doubt, pull the filter and hold it to the light. If you can’t see light through it, it’s past time.
Homeowners sometimes reach for the highest MERV rating they can find, thinking more is better. High MERV filters capture finer particles, but not every system can handle the added restriction. If your blower is undersized or your return duct is tight, an ultra-high MERV filter can pinch airflow and do more harm than good. When we assess a house in Peru or the surrounding area, we look at static pressure and blower capacity before recommending a filter. For many systems, a pleated MERV 8 to 11 strikes the right balance. If allergies are a concern, we often pair a mid-MERV filter with UV or electronic air cleaning so the blower stays happy.
The coil you forget: give the outdoor unit room to breathe
The outdoor condenser is a heat rejection machine. It pulls heat out of your refrigerant and dumps it to the outside air. It does this using very thin aluminum fins that need clear airflow from all sides. When those fins clog with cottonwood fluff or grass clippings, the refrigerant can’t shed heat efficiently. Pressures rise, compressor temperatures climb, and your house feels less cool even though the system runs longer.
Walk the perimeter of the unit. It needs 18 to 24 inches of clearance on every side and at least five feet above. Trim shrubs back to give that breathing room. If mulch or ivy crowds the base, pull it back. I’ve cleared more rodent nests and toy collections from condenser bases than I care to admit. Keep the top grate clear as well. A storm can drop leaves and small branches that choke airflow.
Cleaning the coil is straightforward for most homeowners. Shut power at the disconnect box or the breaker, then rinse from inside out if you can access it, and then outside in, using a gentle spray that doesn’t bend fins. Skip the pressure washer. Use a coil-specific cleaner if the grime is oily, and rinse thoroughly. If the fins have been flattened by a dog’s curiosity or a soccer ball, a fin comb can straighten them, but be patient. Bent fins cut performance.
Be mindful of landscaping changes. Gravel paths and string trimmers kick debris right into the coil. I’ve stopped more than one repeat service call by shifting a mower path and adding a simple condenser pad to raise the unit above where the clippings land.
The coil you never see: keep the indoor side dry and clean
Evaporator coils sit in dark, damp boxes. They do a lot of work and collect whatever your filter misses. When they get slimy or dusty, airflow falls and odors rise. In homes with high humidity or long runtimes, you also see condensate pans that grow algae or rust through.
While most homeowners won’t pull the coil door every season, there are a few checks you can do without disassembly. First, listen for gurgling in the condensate drain during operation. That can signal partial blockage. Second, watch for water around the furnace or air handler, which points to a clogged drain or a cracked pan. Third, look for ice on the copper refrigerant lines upstream of the coil, a sign of either airflow issues or low refrigerant charge.
Drain maintenance goes a long way. The drain line usually has a cleanout cap near the coil. Removing the cap and pouring a cup of white vinegar through the line once or twice per cooling season helps control algae. If your line ties into a floor drain, confirm you still have a water trap in the floor drain itself. Dry traps let sewer gas into the house. Pour a quart of water into the floor drain if it looks dry.
If your system has a float safety switch in the drain pan, test it at the start of summer. Gently lift the float to simulate a high water event and confirm the system shuts off. Then reset it. That five-second test prevents a flooded basement.
When we service coils at Summers Plumbing Heating & Cooling, we measure static pressure before and after cleaning. If the pressure drops significantly, the coil was restricting airflow. We also check temperature drop across the coil. Healthy systems in our climate usually show a delta T of around 16 to 22 degrees, depending on indoor humidity. Numbers outside that range point to deeper issues that deserve a tech’s attention.
Thermostats, schedules, and the myth of “set to 68 to cool faster”
Your thermostat does not control cooling speed. It tells the system when to run. If it’s set to 68 and your house is at 78, the system will run just as hard as it would if set to 74, it will simply run longer. Use that to your advantage with a schedule that matches your life, not the myth that lower settings cool faster.
Smart thermostats are handy, but they aren’t a cure-all. I’ve removed my share of smart models that were poorly located. A thermostat in direct sun or near a supply vent will get false readings and short-cycle your system. Keep it on an interior wall, roughly five feet off the floor, away from heat sources and drafts. If you installed your own thermostat, double check that you used the correct equipment settings for your system type. Mismatched settings can disable important features like dehumidification on variable-speed equipment.
Battery-backed models deserve a spring battery swap even if they show “good.” Low batteries cause erratic readings that look like refrigerant problems. On service calls where a system otherwise checks out but runs in odd spurts, a new set of batteries sometimes solves the puzzle.
If you like a cooler bedroom, consider a gradual evening setback. Dropping two degrees an hour before bedtime is easier on the system than a big swing right before lights out. In older homes with mixed insulation quality, gently staged changes prevent extended run times and limit humidity spikes.
Ducts and rooms that never cool evenly
Uneven cooling isn’t always an AC problem. It’s often a duct problem. I’ve measured perfect supply air temperatures at the plenum and found 10 degree losses by the time air reached a distant bedroom through a crushed flex run. Basements converted to living spaces without added returns also suffer. The air goes in, but it can’t get back to the blower.
Walk your ductwork if it’s accessible. Look for disconnected joints, ragged tape jobs, and crushed flex. Rigid elbows replaced with tight-radius flex bends can choke flow. If you see gaps, use mastic or foil tape rated for ducts, not cloth duct tape, which dries out and falls off. In older Indiana homes, we often find panned returns that pull air through joist cavities. Those can work, but only if the cavities are reasonably sealed. Otherwise, you’re pulling from the basement or crawlspace and adding dust and humidity to the system.
Registers need space to breathe. Rugs and furniture placed over supplies or returns cripple distribution. One summer, a client in Peru couldn’t cool a living room no matter how low the thermostat went. The culprit was a new sectional parked over the only return in that room. We shifted the sofa six inches and the room dropped four degrees in under an hour.
If zoning or serious duct changes aren’t in the cards, a handful of thoughtful tweaks can help. Balancing dampers near the plenum can shift airflow toward stubborn rooms. Adding a jumper duct or transfer grille between a closed bedroom and the hallway gives return air a path. On two-story homes, closing a few downstairs supplies slightly in late afternoon can favor upstairs comfort without overburdening the blower.
The condenser fan and the quiet signals of wear
Compressor failures grab attention, but condenser fan motors give subtle warnings long before they quit. A fan that starts reluctantly, squeals briefly, or runs hot to the touch may have a weakening capacitor or failing bearings. Capacitors are inexpensive and often the first part to age out in our summer heat. On maintenance visits, we test capacitance values and compare to the nameplate. A 10 percent drop is a red flag.
Noise changes matter. A growl from the contactor points to pitted contacts. A chattering contactor can starve a compressor of voltage and shorten its life. The fix is well within a tech’s scope and not expensive. If your condenser rattles at startup, check the fan shroud and top panel for loose fasteners. Vibration transmits noise into the home and shakes parts loose over time.
Electrical connections benefit from a once-a-year tightening under safe, powered-off conditions. Aluminum lugs in particular can loosen as metals expand and contract across seasons. A half-turn with the correct torque can stop heat from building at the connection. We carry thermal cameras to spot hot connections in seconds.
Refrigerant: when to leave it alone and when to act
Homeowners often ask for a “recharge” as if refrigerant were a consumable. It’s not. A sealed system that’s low on charge has a leak. Topping it off without finding the leak is like refilling a tire with a nail in it. You may get a few weeks of comfort, but you’re courting bigger problems, including oil loss that starves the compressor.
Modern systems primarily use R‑410A, though you may still see older R‑22 units. R‑22 is phased out, and replacement costs can surprise. If your R‑22 system develops a leak, we’ll walk you through the economics carefully. Sometimes a coil replacement buys a few more reliable years. Other times the energy savings and reliability of a new R‑410A or next-generation system make more sense. We never push a replacement if a practical repair will deliver reasonable life at a reasonable cost.
Signs of a low charge include frost on the suction line near the condenser, a hissing indoor coil, and low suction pressure with high superheat readings. Those are not DIY diagnoses. What you can do is describe symptoms precisely. Tell your tech when the unit struggles, how long it runs, and whether certain rooms suffer more. Good notes shorten the visit and focus the search.
How humidity fits into the comfort picture
On humid Indiana days, a home at 75 degrees with 50 percent relative humidity feels better than a home at 72 with 65 percent humidity. High indoor moisture makes sweat less effective, so you feel sticky and restless. Your AC is a dehumidifier by design, but it only removes moisture when air passes over a cold coil long enough for condensation to form and drain.
Oversized systems short-cycle, which reduces moisture removal. They meet the thermostat setpoint quickly but don’t run long enough to pull water from the air. If your home always feels muggy despite reasonable temperatures, an oversized AC may be the reason. Variable-speed systems help by running longer at lower capacity. On single-stage systems, we can often adjust blower speed and confirm a proper refrigerant charge so the coil operates in the sweet spot for latent removal.
Keep an eye on sources. Unvented gas appliances, damp basements, and long showers without a good exhaust fan add moisture your AC has to handle. A dedicated whole-home dehumidifier can be a smart addition in basements or in homes where shoulder-season humidity is a problem when the AC doesn’t run much.
Practical schedule for a no-drama cooling season
Different homes need different cadence, but a simple rhythm works for most.
- Every 30 to 60 days during heavy use: check and replace the air filter as needed, clear debris from around the outdoor unit, and confirm the thermostat is behaving as expected. At the start of the cooling season: rinse the outdoor coil, test the condensate safety switch, pour vinegar through the drain, change thermostat batteries, and run the system long enough to confirm steady cooling and normal noises. Mid-season: quick visual of refrigerant lines for frost, listen for condenser fan changes, verify steady temperature drop at a supply register, and recheck plant growth around the condenser. After storms or yard projects: check that the condenser is level, confirm panels are tight, and verify the disconnect hasn’t been jostled loose. Once a year with a professional: full system inspection with electrical testing, capacitors checked, contactor condition assessed, coil cleanliness evaluated, refrigerant pressures and superheat/subcooling measured, and duct static pressure recorded.
That’s one list. It’s your seasonal checklist, and it prevents the vast majority of breakdowns I’m called to fix on sweltering afternoons.
Common myths that cost comfort and money
People love rules of thumb. Some help. Some mislead. Three that deserve retiring:
The freezer trick. Setting the thermostat extremely low does not speed cooling. It extends run time and risks coil icing if airflow is marginal. Better to pick a realistic setpoint and let the system work steadily.
Closed doors for faster cooling. Shutting bedroom doors can starve returns and raise pressures in ways that hurt airflow. If privacy is a must, consider transfer grilles or undercut doors that still allow air back to the return.
Covering the condenser for summer debris. A tight cover during operation suffocates the coil. Use a breathable top cover only in the off season if leaves are a problem, and remove it well before you start the unit.
When to call a professional without waiting
DIY has its limits. If you notice breaker trips when the AC starts, repeated icing on refrigerant lines, a chemical or burnt electrical smell, or water near the air handler, shut the system down and pick up the phone. Quick action prevents compounding damage. If a breaker trips more than once on startup, do not keep resetting it. That points to a hard-start condition, failing capacitor, or compressor problem that needs a meter and experience.
For homes with elderly residents, infants, or medical needs, I recommend a proactive spring tune-up with precise testing rather than a reactive service call in July. A 60 to 90 minute professional visit with numbers on paper is cheaper than a ruined weekend and an emergency surcharge.
What a thorough tune-up actually includes
People hear “tune-up” and imagine a quick spray and a pat on the back. That’s not how we work. On a proper maintenance visit, we measure static pressure to verify duct health, temperature rise or drop across the coil, superheat and subcooling to gauge refrigerant performance, capacitor values against their labeled microfarads, contactor condition, compressor amp draw against nameplate, and blower cleanliness. We inspect the condenser coil all the way around, not just the visible side. We flush the drain and test safety switches. If we spot hot electrical connections with a thermal camera, we correct them.
Numbers give you a baseline. If next year’s readings shift, we know where to look. A system might feel “fine” while drifting away from optimal operation. Catching that drift saves energy and wear.
A short summer story from the field
Last July, a family south of Peru called with a familiar complaint: the upstairs wouldn’t cool and the unit ran nonstop. The outdoor coil looked clean at a glance. But static pressure told the real story. High on the return side, normal on the supply. We pulled the filter, and the pressure barely changed. That pointed to the coil or the return duct, not the filter. The coil door had never been opened in years. Under the panel, the evaporator coil was caked with a thin felt of dust and pet hair that had slipped past a string of bargain filters. We cleaned the coil, flushed the drain, and set them up with a better-filter media cabinet. Their delta T snapped back to 20 degrees, and the second floor dropped to setpoint without the unit running flat-out. Their bill the next month fell by about 18 percent compared to the same period the previous year, adjusted for weather.
The moral is simple. Looks can mislead. Instruments and method beat guesswork.
Planning for replacement without pressure
Even with great maintenance, every system reaches a point where repairs stop making sense. Compressors age. Coils leak. Controls become obsolete. We look at three variables when advising on replacement: repair cost as a fraction of replacement cost, system age relative to typical lifespan, and the efficiency gain of a new unit in your specific home. If a major repair crosses roughly a third of replacement cost on a system beyond the 10 to 12 year mark, replacement often pencils out, especially if your energy bills are already high or if comfort has been marginal.
Newer variable-speed systems unlock better humidity control and quieter operation. They need proper Cooling solutions by Summers Plumbing commissioning. That means verifying charge by weight and performance, confirming airflow with measured static pressure and blower tables, and setting up thermostat profiles correctly. Slapping in a high-end unit without commissioning wastes its potential.
If you anticipate a replacement within a year or two, a sensible plan includes a quick duct assessment and any modest sealing or balancing improvements that give your new system the best platform. Small investments in ductwork can magnify the benefits of a new AC.
The human factor: small daily habits that help
Windows closed during peak humidity hours matter more than most expect. Cooking with lids on and running bath fans through showers reduces moisture load. Keeping blinds down on the west side during late afternoon knocks several degrees off indoor heat gain. We’ve charted homes where those simple habits cut runtime by 30 to 60 minutes during the hottest hours.
Don’t ignore smells. A sweet, solvent-like odor near the air handler can hint at a refrigerant leak. A musty smell that appears when the system first kicks on may come from a damp return or a dirty coil. Early clues lead to easy fixes.
Finally, build a relationship with a trusted local team. When a tech knows your home’s quirks, they arrive prepared with the right parts and context.
Need a hand or a second set of eyes?
Contact Us
Summers Plumbing Heating & Cooling
Address: 2589 S Business 31, Peru, IN 46970, United States
Phone: (765) 473-5435
Website: https://summersphc.com/peru/
Whether you want a spring tune-up with real numbers, help diagnosing uneven cooling, or a plan for the next upgrade, we’re here to make summer simple. Clear steps, no scare tactics, and workmanship that holds up when the heat hits.