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November 3, 2025

Gas City, IN Heat Pump Not Cooling? 5 Reasons

Estimated Read Time: 9 minutes

A heat pump not cooling can turn a muggy Indiana afternoon into a long night. Before you panic, most problems are fixable with the right steps. In this guide, you will learn the top causes of weak or warm air, simple checks you can do today, and when to call Summers Plumbing Heating & Cooling for fast help in Marion and nearby cities. If you are on a maintenance plan, some fixes may even be covered.

1) Dirty Outdoor Coil or Clogged Air Filter

Your heat pump cools by moving indoor heat to the outside. If the outdoor coil is covered in cottonwood, leaves, or road dust, or if your return filter is clogged, airflow tanks and the system cannot move heat out. The result is longer run times, lukewarm vents, and a higher bill.

Quick checks you can do:

  1. Turn the system off at the thermostat. Replace a 1‑inch filter every 30 to 60 days during summer. High‑MERV filters load faster.
  2. Inspect the outdoor unit. Clear grass, mulch, and debris at least 24 inches around the cabinet. Gently rinse from the inside out if you can access it safely.
  3. Make sure supply and return grilles are open and not blocked by furniture or rugs.

If airflow does not improve, the coil may need a professional cleaning, which includes a safe chemical rinse, fin straightening, and a system static pressure check. Our precision tune‑up includes these steps and checks duct restrictions that starve the blower.

2) Thermostat or Mode Settings Incorrect

It sounds basic, but wrong settings cause many heat pump not cooling calls. A thermostat left in Heat mode, or an auto changeover with a tight differential, can short cycle between heating and cooling. A mismatched schedule can also bump the setpoint higher than you expect.

Simple steps:

  1. Confirm Cool mode with a setpoint at least 3 degrees below room temperature.
  2. Set the fan to Auto, not On, to avoid blowing warm air between cooling cycles.
  3. If you have a dual‑fuel system, check the balance point settings. Incorrect lockouts can force the wrong stage.
  4. Replace weak thermostat batteries and ensure Wi‑Fi schedules match your routine.

If your thermostat was recently upgraded, it may need proper heat pump configuration, including reversing valve setting, staging, and sensor calibration. Our techs program and verify these during maintenance so your system behaves correctly when Indiana weather swings from cool mornings to hot afternoons.

3) Low Refrigerant or a Hidden Leak

When refrigerant is low, your heat pump not cooling is more than a comfort issue. Low charge reduces coil temperature, which lowers capacity and can cause icing. Ice on the indoor coil or refrigerant lines is a red flag. Topping off refrigerant without leak testing is not a fix and can shorten compressor life.

What we do on a proper repair:

  1. Measure superheat, subcooling, and line temperatures. We never guess by pressure alone.
  2. Perform electronic leak detection and, if needed, isolate the leak with nitrogen testing.
  3. Repair the leak, replace the dryer, evacuate to 500 microns, and weigh in the factory charge.

This method protects your compressor and restores efficiency. Summers backs HVAC work with a one‑year labor and manufacturer warranty, and we offer financing if a large repair or replacement is the better long‑term move.

4) Frozen Coil or Drain Problems

A heat pump that ices up indoors or outdoors will blow warm air or cycle off on safety. Restricted airflow, dirty coils, or low charge cause freeze‑ups. A plugged condensate drain can also trip float switches and shut cooling down to prevent water damage.

Homeowner steps:

  1. If you see frost, turn the system to Off and the fan to On for 60 minutes to thaw.
  2. Check for a wet filter or water at the indoor unit. Clear the drain trap if you can do so safely.
  3. After thawing, restart in Cool, then watch for new ice over the next hour.

If ice returns, schedule service. We check blower speed, static pressure, coil cleanliness, charge, and the defrost board. In Marion and Gas City, cottonwood season and farm dust make freeze‑ups common in late spring. A precision tune‑up lowers that risk by cleaning coils and verifying airflow before peak heat.

5) Outdoor Unit Not Running or Short Cycling

If indoor air handler runs but the outdoor unit is silent, your heat pump not cooling could be due to a failed capacitor, contactor, or high‑pressure switch trip from poor airflow. Rapid on‑off cycling can point to failing fan motors, weak capacitors, or a thermostat issue.

What to look for safely:

  1. Listen for a low hum at the outdoor unit. A hum with no fan often means a bad capacitor.
  2. Inspect the disconnect for signs of burn or corrosion. Do not touch live parts.
  3. Shade, mulch, or fences too close to the unit trap hot air and force safety trips.

Our technicians are licensed and background checked, and we stock common parts on the truck so most no‑cool calls are fixed same day. For older systems, we provide side‑by‑side repair vs. replace options with clear pricing that we match or beat.

When Your Heat Pump Is Running But The Home Still Feels Humid

Indiana summers bring high humidity, which can make 72 degrees feel sticky. Heat pumps remove moisture as they cool, but poor airflow, oversized equipment, or a single‑stage system that short cycles can leave the air damp. Leaky return ducts pulling hot attic or crawlspace air also overload the system.

Improvements that work:

  1. Balance airflow and verify total external static pressure.
  2. Add a whole‑home dehumidifier or upgrade to a variable‑speed heat pump for longer, gentler cycles.
  3. Seal and insulate return ducts, especially in attics or garages.

Summers also offers indoor air solutions like filtration and dehumidification to support cooling performance. Ask about our safety and comfort maintenance plan. Many Marion homeowners pair it with annual coil cleanings and drain treatments to stop microbial growth.

DIY Checklist Before You Call

Use this fast list to rule out simple causes of a heat pump not cooling:

  1. Thermostat on Cool, fan on Auto, correct schedule.
  2. New air filter installed, all vents open.
  3. Outdoor unit cleared 24 inches on all sides, coil rinsed gently.
  4. Breakers on, service disconnect seated.
  5. No ice on the refrigerant lines. If iced, thaw first.
  6. Check for water at the furnace or air handler. Clear the drain if safe.

If the system still struggles, book a pro visit. We provide 24/7 emergency service across Marion, Kokomo, Huntington, Wabash, and nearby towns along the I‑69 corridor. Fast response protects your compressor and can save on energy bills.

Repair, Maintenance, or Replace: How to Decide

Not every heat pump not cooling call needs a new system. We follow a transparent process:

  1. Diagnose and quote a firm repair price. We will match or beat any competitor’s price.
  2. If repairs exceed 30 to 40 percent of a new system cost and the unit is near end of life, we present replacement options.
  3. Discuss comfort goals, humidity, noise, and efficiency. Variable‑speed systems often solve hot‑spot and humidity issues.

Hard facts that protect your investment:

  1. Summers provides a one‑year labor and manufacturer warranty on HVAC services. Air conditioning units can qualify for up to a 10‑year labor warranty, and select AC replacements can carry a lifetime equipment warranty.
  2. We have served Indiana homeowners for over 40 years with 24/7 emergency availability and background‑checked technicians.

With flexible financing and periodic specials, we make the right solution affordable without upselling anything you do not need.

Why Routine Tune‑Ups Stop No‑Cool Emergencies

Precision tune‑ups catch small problems before they become heat pump not cooling disasters. Our visit includes coil cleaning, electrical testing, refrigerant performance checks, drain treatment, and thermostat calibration. We also measure static pressure to spot duct issues that rob capacity.

Plan benefits our customers love:

  1. Priority scheduling during heat waves and cold snaps.
  2. Documented performance readings you can compare season to season.
  3. Savings on repairs and no breakdown guarantees on select services.

Homeowners across Marion and Hartford City tell us the plan pays for itself in comfort and fewer surprises. Ask about pairing maintenance with indoor air upgrades for even better cooling and cleaner air.

What Homeowners Are Saying

"Craig and Alexander did a bang up job installing my new heat pump. They were very professional and knowledgeable concerning the job. I will use Summer's to take care of my heating and cooling needs."
–Bill M., Marion Area
"Shanea was the maintenance representative from Summers Heating and Cooling. She serviced 2 furnaces and air conditioners at our home. One furnace is a heat pump and the other furnace is gas... She did a wonderful job of cleaning and serving the units."
–Cyndi F., Marion

Frequently Asked Questions

Why is my heat pump running but not blowing cold air?

Common causes are dirty coils, clogged filters, low refrigerant, or wrong thermostat settings. Start with a new filter, confirm Cool mode, and clear debris outdoors. If the air stays warm, schedule a diagnostic.

Can low refrigerant damage my heat pump?

Yes. Low charge reduces cooling capacity, causes icing, and can overheat the compressor. A proper fix includes leak testing, repairing the leak, evacuating, and weighing in the correct charge.

How often should I service my heat pump?

Twice a year is ideal. Schedule spring cooling and fall heating tune‑ups. This includes coil cleaning, electrical checks, drain treatment, and thermostat calibration.

Will a dehumidifier help if my home feels sticky?

Often yes. A whole‑home dehumidifier paired with a variable‑speed heat pump improves moisture control and comfort without overcooling.

When should I consider replacing instead of repairing?

If repairs are frequent, the unit is near end of life, or the repair cost is 30–40 percent of a new system, replacement can be smarter. We provide side‑by‑side options and financing.

In Summary

A heat pump not cooling is usually caused by airflow issues, wrong settings, low refrigerant, icing, or outdoor unit failures. Tackle the quick checks, then call a pro if comfort does not return. For fast fixes and proven maintenance in Marion, Kokomo, Wabash, and nearby, we are ready to help today.

Ready for Cool, Dry Air Again?

Call Summers Plumbing Heating & Cooling at (765) 613-0053 or schedule online at https://www.summersphc.com/marion/. Ask about our safety and comfort maintenance plan, 24/7 emergency service, and price‑match guarantee. Get your system checked the right way and enjoy reliable cooling all summer.

About Summers Plumbing Heating & Cooling

For over 40 years, Summers Plumbing Heating & Cooling has kept Marion and nearby communities comfortable with honest, high‑value service. Our licensed, background‑checked techs handle heat pump repairs, tune‑ups, and installs. We back our work with a one‑year labor and manufacturer warranty, and we match or beat competitors’ prices. Enjoy 24/7 emergency service, flexible financing, and our Worry‑FREE Guarantee. Local, trusted, and ready to help.

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