Heat Pump & Geothermal System Maintenance & Troubleshooting

Heat Pump & Geothermal Troubleshooting: A Homeowner’s Diagnostic Guide

That moment of uncertainty is something every homeowner knows. You adjust the thermostat, but nothing happens. Or maybe a strange new noise from your heat pump or geothermal system is making you uneasy. Your first thought isn’t about how the system works—it’s about whether this is a quick fix or a costly problem. You need to know what to check yourself and when it’s time to call in a professional.

This guide is built for that exact moment. We’ll walk you through the same diagnostic steps our own technicians use, helping you identify and solve common issues safely. We’ll also give you a clear framework for knowing when a problem is beyond a simple DIY fix.

Your Interactive Symptom Checker

Click on the issue you’re experiencing to jump directly to the troubleshooting steps.

• My System Isn’t Cooling or Heating Properly
• My Unit is Making Strange Noises
• My Energy Bills Have Spiked Unexpectedly
• My System is Leaking Water

Symptom: My System Isn’t Cooling or Heating Properly

This is the most common call we get. Before you assume the worst, let's run through a quick checklist. Often, the solution is simpler than you think.

Step 1: The 5-Minute DIY Check

These are the essential first steps that resolve a surprising number of issues.

1. Check the Thermostat:
   • Is it set correctly? Ensure it’s on “Cool” or “Heat,” not “Off” or “Fan.”
   • Is the temperature set properly? For cooling, set it at least 5 degrees below the current room temperature. For heating, set it 5 degrees above.
   • Check the batteries. If the thermostat display is blank or dim, replace the batteries.
   • Nest Thermostat Users: Make sure your system is set to the correct heat pump type (O or B wire setting). An incorrect setting can cause the system to run in the opposite mode.
2. Inspect the Air Filter: A clogged filter is a primary cause of poor performance. It restricts airflow, forcing your system to work harder for worse results. According to Energy.gov, checking your filter every 3 months is a critical maintenance step.
   • Locate the filter compartment on your indoor unit.
   • Slide the old filter out and hold it up to a light. If you can't see light through it, it’s time for a change.
   • Slide in a new filter, making sure the arrow points in the direction of the airflow.

3. Check the Circuit Breaker: Find your home's main electrical panel. Look for the breaker labeled "Air Handler" or "HVAC" and the one for the "Outdoor Unit" or "Condenser." If either is tripped (usually in the middle position), switch it fully off and then back on once. If it trips again immediately, do not reset it again—this indicates a more serious electrical issue.

Step 2: Advanced Diagnostics

If the basics don’t solve the problem, we can look a bit deeper.

• For Geothermal Systems - Check the Loop Pressure: Your geothermal system has a closed loop of fluid that transfers heat. This loop needs to maintain proper pressure.
  • Locate the pressure gauge on your system's flow center (it often looks like a small pump station near the indoor unit).
  • A healthy residential system typically operates between 30-50 PSI. If the gauge reads significantly below this, you may have a leak in the ground loop. A pressure drop is a clear sign that you need professional AC Repair.

Step 3: The "When to Call a Pro" Decision Framework

Use this table to understand the risks and decide on your next step.

Symptom: My Unit is Making Strange Noises

Unusual sounds can be alarming, but they are often distinct clues to what's going on inside your system.

• Clicking: A rapid clicking when the system tries to start could be an electrical control failing. If it's a single click when it turns on or off, that's usually normal.
• Hissing or Bubbling: This often points to a refrigerant leak. Refrigerant is a controlled substance and can only be handled by a certified technician. Do not attempt to fix this yourself.
• Grinding or Squealing: These mechanical sounds suggest a problem with the fan motor or its bearings. Turn the system off immediately to prevent further damage and schedule a service call.
• Loud Banging: This could be a loose or broken part, such as a connecting rod or piston pin inside the compressor. Turn the system off and call for service.

Symptom: My Energy Bills Have Spiked Unexpectedly

If your usage habits haven't changed but your bill has gone up, your HVAC system is a likely culprit. A well-maintained heat pump can be 10% to 25% more efficient than a neglected one, according to the Department of Energy.

1. Check the Filter: We mention it again because it’s that important. A clogged filter makes your system run longer and harder to cool or heat your home.
2. Inspect the Outdoor Unit: Ensure the area around your outdoor heat pump is clear of leaves, grass clippings, and other debris for at least two feet in all directions. Blocked airflow reduces efficiency.
3. Look for Leaky Ducts: Poorly sealed or insulated ductwork can lose a significant amount of conditioned air into your attic or crawlspace. While a full inspection is best left to pros, you can check for obvious tears or disconnected joints in visible ductwork.

If these checks don't reveal an obvious cause, it's time for a professional tune-up. An expert can check refrigerant levels, clean coils, and test electrical components to restore your system's efficiency. Regular AC Maintenance is the single best way to keep energy costs down.

Symptom: My System is Leaking Water

Water pooling around your indoor unit is usually caused by a clogged condensate drain line. During the cooling season, your system pulls humidity from the air, which collects and drains away. If that line gets clogged with algae or debris, the water backs up.

• DIY Fix: You can often clear this line yourself using a wet/dry vacuum on the outdoor end of the PVC drain pipe.
• When to Call a Pro: If you can't clear the line or if the leak is significant, it's best to call a technician. A persistent leak can cause serious water damage and affect your Indoor Air Quality by promoting mold growth.

Your Proactive Maintenance Schedule

Troubleshooting is for fixing problems. Maintenance is about preventing them from ever happening. Following a simple schedule keeps your system efficient, extends its lifespan, and gives you peace of mind.

Frequently Asked Questions

1. How often should my heat pump or geothermal system be professionally serviced?

‍We recommend a professional tune-up once a year. This allows a technician to clean critical components, test electrical connections, and check refrigerant levels to ensure the system is running safely and at peak efficiency before the extreme weather of summer or winter hits.

2. Can I really save money by doing this maintenance myself?

‍Absolutely. Simple tasks like changing your air filter and keeping the outdoor unit clear of debris can prevent the most common causes of system failure and efficiency loss, saving you from unnecessary service calls and high energy bills.

3. What's the biggest mistake homeowners make with these systems?

‍The most common mistake is ignoring small problems until they become big ones. A strange noise or a slight decrease in performance can seem minor, but it's often a warning sign of a developing issue. Addressing it early is almost always less expensive than waiting for a complete breakdown.

4. Why should I choose a local, family-owned company for repairs?

‍When you work with a company that’s been part of the community for decades, you’re getting more than just a repair. You’re getting a partner invested in your long-term comfort. At Goode Air Conditioning & Heating, we've been "Taking Goode care of our customers" since 1976. We rely on our reputation, not just a transaction. You can learn more About Us and our commitment to our neighbors in Humble, Kingwood, and the surrounding areas.

Your Next Step

If you’ve run through the DIY checks and your system still isn’t working right—or if you’ve identified a problem that requires a professional—your next step is clear. Don't let a small issue turn into a major headache.

When you need a trusted expert to take a closer look, our team is ready to help. We provide transparent, flat-rate pricing and the honest advice you expect from a neighbor. Contact Goode Air Conditioning & Heating today to schedule your service.