Onward, IN Heat Pump Not Cooling? 5 Likely Reasons

Estimated Read Time: 10 minutes

Is your heat pump not cooling like it should? You set a lower temperature, but rooms still feel warm and muggy. This guide explains the most common causes and simple checks you can try right now. If you need a pro, Summers Plumbing Heating & Cooling is ready 24/7 in the Peru area with fast diagnostics, price match or beat, and free estimates.

1) Thermostat settings or modes are incorrect

Small thermostat mistakes cause big comfort problems. Confirm the system is set to Cool, not Heat. Set the fan to Auto, not On. Fan On runs constantly and can push room‑temperature air that feels warm. Lower the setpoint by at least 3 degrees below current room temperature to prompt a cycle.

Check your schedule. A setback or Eco mode can raise temperatures during the day. Disable temporary holds that block cooling. If you use a smart thermostat, verify the heat pump mode and any humidity or adaptive features.

Steps to try:

1. Set mode to Cool and fan to Auto.
2. Drop the setpoint 3 to 5 degrees.
3. Replace low batteries in older thermostats.
4. Reboot a smart thermostat per the manufacturer.
5. Confirm wiring labels if a new thermostat was installed.

If cooling returns, your system is likely healthy. If not, move to airflow checks.

2) Dirty air filter or blocked airflow

Restricted airflow prevents heat from moving out of your home. A clogged filter can cause weak airflow, longer run times, and lukewarm supply air. Severe restriction can even ice the indoor coil.

What to check:

1. Replace the filter if it is gray or dusty. Typical homes need a change every 60 to 90 days. Homes with pets or allergies may need monthly changes.
2. Open all supply registers and return grilles. Try to keep 80 percent or more of registers open.
3. Clear furniture, rugs, and curtains from vents.
4. Inspect the indoor blower compartment for debris if it is accessible and safe.

Pro tip: Cottonwood fluff in late spring around Peru and Logansport can clog outdoor coils and strain airflow. If airflow improves after a filter change, let the system run for 30 minutes and reassess room temperature.

3) Low refrigerant from a leak or improper charge

A heat pump that is low on refrigerant cannot absorb and move heat effectively. You may see ice on the refrigerant lines, hear hissing, or notice longer cycles with poor cooling. Only certified professionals should handle refrigerant. The EPA requires Section 608 certification for refrigerant service.

What to do:

1. Do not scrape ice. Turn the system Off and set the fan to Auto.
2. Let ice melt fully before restarting in Cool.
3. Call for a professional leak check and recharge if needed.

Signs of a leak include oil residue on fittings, repeated icing, and short cycling. A proper fix includes finding and repairing the leak, then weighing in the charge to the correct specification. Topping off without a leak repair often leads to repeat failures.

4) Outdoor unit problems: dirty coil, debris, or fan failure

Your outdoor unit must release heat to the outside. If the coil is dirty or the fan is not spinning, heat cannot escape. The result is warm air from the vents and a system that runs without catching up.

DIY checks:

1. Shut off power before any cleaning.
2. Rinse the coil from the inside out with a gentle hose stream. Avoid high pressure.
3. Trim vegetation at least 18 inches around the unit.
4. Remove leaves, nests, and cottonwood fluff.

If the fan does not spin or you hear squealing, call a pro. A failed capacitor or motor can stop the fan. Running the system with a non‑spinning fan can damage the compressor.

5) Reversing valve, defrost, or sensor issues

Heat pumps rely on precise controls. A stuck reversing valve can leave the system stuck between modes. A faulty defrost board may confuse the unit and interrupt cooling. Bad temperature or coil sensors can cause short cycles or prevent proper staging.

Typical symptoms include warm air at vents during cooling calls, frequent clicking, or brief run times. These parts require diagnostic tools and training. A licensed technician can test solenoid voltage, board logic, and sensor resistance. In many cases, the repair is straightforward once the root cause is found.

When to repair vs replace your heat pump

Most no‑cool issues are repairable. Consider replacement when your system is:

1. Over 12 to 15 years old with frequent breakdowns.
2. Using R‑22 refrigerant or has major component failures.
3. Oversized or undersized for the home, causing humidity or comfort issues.

Newer heat pumps can deliver higher efficiency and better humidity control. ENERGY STAR notes that high efficiency heat pumps can cut heating electricity use by about 50 percent compared to electric resistance heat. That can translate to lower utility bills year round. Ask about equipment that meets current SEER2 and HSPF2 standards for verified performance.

Simple homeowner checklist before you call

Run through these quick steps. Many solve the problem fast:

1. Confirm Cool mode and fan Auto.
2. Replace the air filter.
3. Open supply and return vents.
4. Check the outdoor unit for debris and give it space.
5. Look for ice on lines. If present, turn system Off and allow to thaw.
6. Verify breakers are on at both the air handler and outdoor unit.
7. Reboot your smart thermostat and confirm schedules.

If cooling still struggles after 30 to 60 minutes, schedule service. Continued operation with faults can raise bills and risk compressor damage.

What to expect with a Summers professional diagnostic

Summers Plumbing Heating & Cooling has helped local homeowners since 1969. We provide 24/7 emergency service, same‑day availability, and free estimates. Our licensed, background‑checked technicians follow a proven cooling checklist:

1. Interview the homeowner for symptoms and recent changes.
2. Inspect thermostat settings and electrical connections.
3. Measure static pressure and airflow across the coil.
4. Test capacitors, contactor, and fan operation.
5. Check refrigerant pressures and temperatures to calculate charge.
6. Inspect the outdoor and indoor coils for dirt and damage.
7. Provide clear options with upfront prices. We price match or beat competitors.

We stock common parts for faster repairs. For bigger fixes or replacements, we explain warranty choices. The company lists solid parts and labor warranties, with longer labor coverage for some systems. Ask about financing and our safety and comfort membership for priority service.

Preventive maintenance that keeps cooling strong

Heat pumps work hard in every season. Regular maintenance prevents many no‑cool calls and helps extend system life.

A Summers tune‑up includes:

1. Deep cleaning of indoor and outdoor coils.
2. Filter change guidance and airflow checks.
3. Electrical testing and refrigerant performance checks.
4. Thermostat calibration and drain cleaning.

Our maintenance plans offer scheduled visits, priority status, and no overtime charges for members. The team can also set one‑day replacement for qualifying cases. Routine care reduces surprise breakdowns and helps keep comfort steady through humid Indiana summers and cold snaps in Miami County.

Geothermal and heat pump options if you need an upgrade

If your equipment is old or inefficient, we can review standard and geothermal options. Geothermal systems use the stable ground temperature to heat and cool efficiently. Summers installs geothermal systems and can provide a free in‑home estimate. We will compare initial costs, available incentives, and operating savings so you can decide with confidence.

What Homeowners Are Saying

"Will Allison came out to my home today to do our annual heating tune up. He performed a thorough inspection of every component of our heat pump outside as well as the air handler in our home and gave us a detailed report on the condition of each thing he checked. He also tested and made sure our emergency heat was working properly. I learned a lot today from his visit and our furnace door and that whole area back there hasn't been this clean since I can remember! Will truly went above and beyond and I am so impressed with the level of customer service this young man provided. We will most certainly continue our maintenance program membership with Summers. I don't know how they do it, but Summers has cracked the code when it comes to hiring the very best! I highly recommend this company!!!"
–Will A., Heating Tune-Up

"Nick Elliott with Summers Heating and Cooling in Peru, In did a great job of fixing my heat pump today.i Would recommend Summers to anyone needing this type of work done."
–Nick E., Peru, IN

"Will Allison came out today to check my heat pump and furnace out. He did a thorough inspection and I feel very great about the visit. I joined the maintenance plan and look forward to having my ducts cleaned and sanitized next month. Thank you Summers!"
–Will A., Heat Pump Inspection

"The crew that came out fixed our heat pump. Thank you so much."
–Anonymous, Heat Pump Repair

Frequently Asked Questions

Why is my heat pump blowing warm air in Cool mode?

Thermostat or mode errors are common. Confirm Cool and fan Auto. A dirty filter, low refrigerant, or a failed outdoor fan can also cause warm air.

How long should it take to cool my home a few degrees?

Most systems drop indoor temperature 1 to 2 degrees per hour under normal conditions. Extreme heat or humidity can slow this rate.

Is it safe to run my heat pump if the outdoor lines are iced?

No. Turn the system Off and let it thaw. Ice often points to airflow problems or low refrigerant. Call a certified technician to diagnose.

How often should I change my heat pump filter?

Most homes need a change every 60 to 90 days. Homes with pets, allergies, or renovation dust may need monthly replacements.

Do you service heat pumps after hours?

Yes. Summers offers 24/7 emergency service. Members receive priority scheduling and no overtime charges according to the maintenance plan terms.

In Summary

A heat pump not cooling usually comes down to settings, airflow, refrigerant, outdoor debris, or a control fault. If quick checks do not help, call the local pros. For fast help in Peru and nearby cities, contact Summers Plumbing Heating & Cooling.

Call or Schedule Now

• Call: (765) 473-5435
• Schedule: https://www.summersphc.com/peru/
• Ask about maintenance memberships for priority service and no overtime charges.

Ready for reliable cooling today? Call (765) 473-5435 or book at https://www.summersphc.com/peru/. Free estimates, price match or beat, and 24/7 emergency service across Peru, Logansport, and Miami County.

About Summers Plumbing Heating & Cooling

Family owned since 1969, Summers Plumbing Heating & Cooling delivers fast, affordable HVAC in Peru and nearby cities. Our licensed, background‑checked techs provide 24/7 emergency service, price match or beat, and free estimates. We back work with strong parts and labor warranties and offer maintenance memberships with no overtime charges and priority scheduling. Homeowners in Peru, Logansport, Rochester, and across Miami County trust Summers for dependable heat pump repair, tune‑ups, and replacements.