Lebanon, IN Heat Pump Troubleshooting: No Hot Air?

Estimated Read Time: 9 minutes

If you are dealing with a heat pump not blowing hot air, start here. This quick guide walks you through simple checks that solve most no‑heat calls and helps you know when to call a pro. Crawfordsville winters swing fast, so acting early prevents a chilly home and higher bills. If you need help anytime, our certified technicians are available 24/7 at (765) 310-3070.

First, Confirm the Basics: Thermostat and Mode

Before opening panels, confirm the system is told to heat. Small settings change how a heat pump behaves.

1. Set to Heat, not Cool or Auto. Auto can misread shoulder‑season temps and delay heating.
2. Raise the setpoint 3 to 5 degrees above room temperature.
3. Check Fan setting. Use Auto to let the air handler cycle correctly during heat.
4. Verify the schedule did not override your change. Temporarily use Hold.
5. Replace batteries in battery‑powered thermostats.

If the thermostat is a smart model, reboot it and confirm the correct system type is selected in settings.

"Technician was very friendly very professional discovered that the old system was having problems that were not cost effective... guided me through the whole process."

Airflow First: Filters, Vents, and Returns

Restricted airflow is the top reason a heat pump feels lukewarm.

• Check the filter. If it is gray or clogged, replace or clean it. A dirty filter lowers coil temperature and can trigger safety limits.
• Open supply registers in key rooms and remove floor rugs blocking vents.
• Clear return grilles. A blocked return starves the blower.
• Listen for whistling or rattling. That can signal a collapsed filter or duct issue.

Quick test: hold a tissue to a return grille. It should gently pull to the grille. Weak pull can mean blocked ducts or a blower problem.

Local tip: Crawfordsville and Lebanon homes with older ductwork often collect fall leaves and pet hair near low wall returns. A five‑minute vacuuming can restore steady airflow.

Outdoor Unit: Clear, Clean, and Defrosting

The outdoor unit moves heat into your home. If it is buried in leaves or frost, output drops.

1. Turn power off at the outdoor disconnect before touching anything.
2. Remove leaves and debris. Keep 18 inches of clear space around the cabinet.
3. Inspect the coil fins. If packed with lint or cottonwood, schedule a professional coil wash.
4. Look for frost or ice. A light glaze during cold snaps is normal. Solid ice covering the coil is not.
5. Restore power and watch a cycle. The fan should start, then you should feel gentle heat indoors within several minutes.

About defrost cycles: Heat pumps briefly reverse in cold weather to melt outdoor frost. You may hear a whoosh, the outdoor fan may stop, and indoor air can feel cooler for a few minutes. That is normal. If defrost never happens or ice keeps building, a sensor or control issue needs service.

"I called this morning and they had a technician here by noon. Aaron was very helpful and explained the situation in great detail... Looking forward to many years of trouble-free comfort."

Balance Expectations: What Heat Should Feel Like

Heat pumps deliver steady, moderate‑temperature air rather than very hot blasts. Typical supply air might feel 85 to 95 degrees during mild winter days. If the room warms over time and the system cycles off, it is likely working. If room temperature falls, go deeper.

Try this quick measurement:

• Use a kitchen thermometer at a supply vent and a return grille.
• A 15 to 30 degree temperature rise is common in heating mode. If the rise is under 10 degrees, keep troubleshooting.

Check the Emergency or Auxiliary Heat

Most air‑source heat pumps use electric heat strips or a dual‑fuel furnace as backup heat during very cold weather or defrost.

• If you see AUX HEAT on the thermostat but no warmth, a breaker may be off.
• Check the electrical panel for tripped breakers labeled Air Handler or Heat Strips. Reset once. If it trips again, call for service.
• For dual‑fuel systems, make sure the gas furnace switch is on and the filter is clean.

If the backup stage heats but the heat pump stage does not, a sensor or refrigerant issue may be present.

Breakers, Switches, and Safety Interlocks

Heat pumps have multiple power points. All must be on.

• Outdoor disconnect near the unit must be fully seated.
• Indoor air handler switch looks like a light switch near the unit. Ensure it is on.
• Condensate safety switch can trip if the drain is clogged. If the air handler pan has water, the system may lock out heat for safety.

Never bypass a safety switch. Clear the cause and reset properly.

Condensate Drain and Drain Pan

In heating mode, most indoor coils do not create much condensate, but in our shoulder seasons when the system flips to cooling for a day, sludge can form.

• Shine a flashlight on the drain pan. If you see standing water, the float switch may have cut power.
• Pour a 50/50 mix of warm water and white vinegar into the drain line cleanout to dissolve sludge.
• If the drain backs up again within a week, schedule a professional clearing.

"Thank you so much to Summers and Don Brannon... He arrived at the front of the time window... changed my disgusting air filter. The service plan helps save on costs too!"

Outdoor Temperature and Balance Point

As temperatures drop, heat pumps work harder. Many systems are tuned with a balance point where backup heat assists.

• On very cold nights, expect AUX HEAT to engage. That is normal.
• If your system never reaches setpoint without AUX even when it is mild outside, it may be undersized or low on refrigerant.

Crawfordsville and Thorntown see sharp temperature swings. Proper settings and maintenance maintain comfort without driving up utility costs.

Refrigerant and Coil Issues: When to Call a Pro

Low refrigerant or a dirty indoor coil can cause lukewarm air and long run times. Refrigerant systems are sealed and require licensed handling.

Signs that point to a professional diagnosis:

• Frost building up quickly on the outdoor coil in mild weather
• Bubbling or hissing at the indoor unit
• Oil stains on refrigerant lines
• Temperature rise under 10 degrees even with clean filters and clear coils

Our technicians use digital gauges, measure superheat and subcooling, check defrost sensors, and test blower speeds against manufacturer specs. If a leak is found, we present repair versus replacement options with upfront pricing.

"New furnace and ac setup... Just that confirmation from a friendly, knowledgeable professional meant a lot! We love our new unit! We love the service call!"

Ductless Mini‑Splits: Special Checks

If your home uses ductless heads:

1. Open the front panel and clean the two washable filters. Rinse, dry fully, and reinstall.
2. Set the mode to Heat and fan to Auto. Avoid Dry or Cool.
3. Ensure the outdoor mini‑split has clear airflow and no ice.
4. Confirm the remote has fresh batteries and is pointed at the head when changing modes.

If one head heats and another does not, a zone valve or sensor issue may be present.

Dual‑Fuel Systems: Heat Pump + Gas Furnace

Dual‑fuel lets your system switch to gas heat at lower outdoor temperatures for efficiency. If you get no heat:

• Confirm thermostat is set to Heat and system type is dual‑fuel.
• Check the furnace switch and panel door. A loose door switch can stop heat.
• Verify gas supply is on and the furnace status light shows a normal code.

If the furnace heats but the heat pump stage does not, or the switch point feels wrong, we can recalibrate the balance point and stage controls.

Safety Checks You Can Do in 3 Minutes

• Smell for burning plastic. Turn the system off if detected and call us.
• Look for tripped breakers. Reset once only.
• Confirm outdoor fan spins freely by hand with power off. If it is stuck, do not force it.
• Make sure pets and leaves are not blocking returns.

Maintenance That Prevents No‑Heat Calls

Routine service keeps performance consistent and bills lower. Because heat pumps both heat and cool, they should be serviced twice a year. Spring and fall tune‑ups are optimal to catch issues before peak seasons. Our checklist includes filter service, electrical inspections, refrigerant pressure checks, thermostat calibration, clearing debris from the outdoor unit, lubrication of moving parts, coil cleaning, condensate drain clearing, and full system performance testing.

Two grounded facts you can count on:

• Summers Plumbing Heating & Cooling has provided HVAC service for more than 40 years across Indiana communities.
• Our team offers 24/7 availability and same day service, so you get help when you need it most.

Preventive benefits you will notice:

1. Lower energy use from clean coils and correct refrigerant charge
2. Fewer emergency repairs thanks to early detection
3. Longer system life with proper lubrication and electrical tightening
4. Quieter operation from balanced blower speeds

Repair or Replace: Making the Smart Call

If your unit is older, needs frequent repairs, or struggles every winter, a replacement may be the better long‑term choice. We install air‑source heat pumps, ductless mini‑splits, and dual‑fuel systems. Our process starts with a home evaluation to review insulation and layout, followed by a clear quote. Installations follow manufacturer guidelines and end with a walkthrough so you know exactly how to operate your new system.

Financial clarity matters. We offer financing options and flexible payment plans. We also monitor local specials to help you save on upgrades and tune‑ups.

Quick DIY Checklist Before You Call

1. Thermostat on Heat, setpoint raised, Fan on Auto
2. Clean or replace filter
3. Open vents and clear returns
4. Outdoor unit cleared of leaves and ice, 18 inches around
5. Breakers on for air handler, heat strips, and outdoor unit
6. Drain pan dry, condensate line clear
7. For dual‑fuel, furnace switch on and door secure

If these do not restore heat within one cycle, schedule a diagnostic.

Why Crawfordsville Homeowners Choose Us for Heat Pump Service

• Certified, continuously trained technicians using modern tools
• Honest pricing and clear explanations before work begins
• 24/7 emergency response and same day service
• Local insight into seasonal temperature swings from Lafayette to Ladoga
• Strong warranties and options for financing to fit your budget

Ready for fast, reliable heat? Call (765) 310-3070 or schedule online at summersphc.com/crawfordsville.

Frequently Asked Questions

Why is my heat pump blowing cool air in heat mode?

A heat pump delivers warm but not hot air. If the home is not warming, check the thermostat mode, filter, breakers, and outdoor unit for ice or debris. If the temperature rise is under 10 degrees after checks, call for service.

How long should a defrost cycle last?

Most defrost cycles last a few minutes. You may hear a whoosh, the outdoor fan may stop, and indoor air can feel cooler briefly. If ice returns quickly or cycles repeat often, a sensor or control issue needs a technician.

Should I use Emergency Heat when it is very cold?

Only if the heat pump stage is not working or during a failure. Emergency Heat forces backup heat, which costs more to run. If you need it to stay warm, schedule a repair.

How often should I service my heat pump?

Twice a year. Spring and fall tune‑ups prepare the system for peak seasons. Maintenance includes filter service, electrical checks, refrigerant pressures, thermostat calibration, coil cleaning, and drain clearing.

Do I need to cover my outdoor unit in winter?

No. Keep it clear by 18 inches on all sides and remove leaves or snow. Covers can trap moisture and restrict airflow, which harms performance.

In Summary

If your heat pump not blowing hot air, start with thermostat, airflow, and outdoor unit checks. When performance still lags, our certified team is ready to diagnose sensors, controls, or refrigerant issues. For dependable comfort in Crawfordsville and nearby cities, we are here 24/7.

Call to Schedule

Call (765) 310-3070 or book at summersphc.com/crawfordsville. Ask about current specials and financing on repairs or new systems. Stay warm and save with a spring or fall tune‑up today.

Call now: (765) 310-3070 • Book online: summersphc.com/crawfordsville • Ask about current specials on heat pump repairs and tune‑ups.

About Summers Plumbing Heating & Cooling

For 40+ years, Summers Plumbing Heating & Cooling has helped Indiana homeowners with honest pricing, same day service, and 24/7 emergency support. Our drug tested, background checked, and licensed technicians are continuously trained on modern heat pump systems. We back our work with dependable warranties and flexible financing. From Crawfordsville to Lafayette and Lebanon, homeowners trust us for quality installations, repairs, and maintenance done right the first time.