Central Air Conditioning Repair in Des Moines, IA
Your air conditioner stopped working on the hottest day of summer—and you need it fixed now. Obsidian Heating and Cooling understands the urgency. We've been the trusted repair specialist for Des Moines homeowners since 2009, delivering fast diagnosis, honest recommendations, and same-day service when emergencies strike. Whether your AC won't turn on, is leaking refrigerant, or is running but not cooling, our veteran-owned team of expert technicians knows exactly what to look for. We're a Tempstar Elite Dealer with direct manufacturer support, which means we can often source and install parts faster than our competitors—getting your home comfortable again without weeks of waiting.
What Sets Our AC Repair Service Apart
Get Fast AC Repair Service
Don't wait in the heat. Contact us now for same-day or emergency service:
Warning Signs Your AC Needs Professional Repair
AC Won't Turn On (No Power, No Cooling)
If your thermostat is set to cool but nothing happens—no compressor hum, no fan, no airflow—the problem could be electrical. Start simple: check the circuit breaker and reset it if it's tripped. Check that the thermostat batteries aren't dead (if it's a battery-powered model) and that the thermostat is actually set to "Cool" (not "Off"). If that doesn't fix it, the issue is likely a blown contactor (the electrical relay that fires up the compressor), a failed transformer, or a tripped safety disconnect outside. These problems require a technician's diagnostic equipment to identify. Don't delay—compressor failures often start with electrical issues that get worse with every failed startup attempt.
System Runs But No Cooling (Fan on, AC Blowing Warm Air)
This is the most common repair call, and the cause usually narrows down quickly. First, check your air filter—a clogged filter restricts airflow and can trigger a safety shutdown. If the filter is fine, the problem is likely low refrigerant (often from a slow leak), a frozen indoor coil (usually from low airflow or refrigerant), a failed compressor (which means the outdoor unit is spinning but not pumping refrigerant), or a broken expansion valve. Our technicians test system pressures in the first 10 minutes of diagnosis and will tell you exactly what's happening.
Refrigerant Leaks (Visible Oily Spots, Weak Cooling Over Time)
Refrigerant doesn't evaporate—if your system is low on charge, there's a leak somewhere. Slow leaks are invisible to the naked eye but show up in our pressure gauges. Over weeks or months, your cooling capacity drops gradually. Fast leaks (usually at the outdoor unit or indoor coil) produce visible oily residue around the connection points. Never try to "top off" refrigerant yourself—modern systems use specific blends, and overcharging is just as harmful as undercharging. We'll find and repair the leak, then evacuate and recharge the system to factory specs.
Outdoor Unit Not Running (Compressor Silent, No Humming)
If the indoor fan is running but the outdoor condenser unit is dead, several issues are possible. The contactor (outdoor relay) might be stuck or failed. The capacitor (which gives the compressor a startup kick) might be blown. A safety disconnect switch might be tripped. A blown breaker or fuse might have cut power. Or the compressor itself might have failed. We'll systematically test electrical supply, controls, and the compressor itself to pinpoint the problem.
Leaking Water Inside or Around the Unit
Water leaking inside your home usually means the condensate drain line is clogged. This is one of the easiest and least expensive fixes—we'll clear the blockage and potentially install a safety float switch that shuts the system down if the backup happens again. Leaks coming from the outdoor unit usually indicate a refrigerant or connection issue and require more involved repair.
Strange Noises (Hissing, Screaming, Grinding, Banging)
Hissing from the outdoor unit usually signals a refrigerant leak. Screaming is often a failed or failing compressor. Grinding or banging inside the indoor unit might be a fan blade hitting the housing or debris in the airstream. Banging from the outdoor unit could indicate a failing compressor or loose components. Never ignore strange sounds—they're your air conditioner's way of telling you something is wrong, and the longer you run it, the worse the damage gets.
How We Diagnose and Repair Your AC System
From emergency intake to performance verification, every step is handled with precision and expertise. Here's what to expect when you choose Obsidian Heating and Cooling for your AC repair.
Emergency Intake & Safety Assessment
When you call, our dispatcher asks quick qualifying questions: Is it an emergency? What's the system doing (or not doing)? Is it under warranty? Do you remember when it was last serviced? This helps us dispatch the right level of technician and bring the right tools. When the technician arrives, they'll check for immediate safety hazards—refrigerant leaks around the indoor coil (poor air quality), electrical shorts, or carbon monoxide concerns (if a gas furnace is involved).
Safety always comes first. If we detect a hazard, we'll shut the system down safely and explain what needs to happen next. We'll never leave you with equipment running in an unsafe state.
What We Check First
Qualifying Questions
Emergency status and system symptoms.
Right Tools Dispatched
Diagnostic equipment sized to your system.
Safety Scan
Visual inspection before electrical work.
Outdoor Unit Check
Debris, damage, or unusual conditions.
Indoor Air Handler
Leaks or visible damage inspection.
Power Verification
Circuit breakers and electrical supply.
Systematic Electrical & Mechanical Testing
This is where expertise shows. We use a digital multimeter to test voltage at the thermostat, contactor, transformer, and compressor. We measure capacitor health with a capacitor tester. We check whether the compressor is receiving power and attempting to start. For refrigerant-related issues, we attach manifold gauges to the low and high pressure ports on the outdoor unit, allowing us to see real-time pressures and compare them to factory specifications.
If pressures are low, the refrigerant is leaking and we need to find the leak. If pressures are normal but the compressor isn't cooling, the compressor has internally failed. If the compressor isn't even trying to start, it's an electrical control issue. This systematic approach takes 15–30 minutes but eliminates guessing.
Testing Procedures
Pressure Gauges
Refrigerant charge and circuit pressures.
Voltage & Amperage
Electrical feed to compressor confirmed.
Capacitor Testing
Dedicated capacitor meter used.
Temperature Differential
Indoor and outdoor coil performance.
Leak Detection & Repair (If Applicable)
If we determine the system is low on refrigerant, finding the leak is critical. Most leaks occur at brazed solder joints (connections between the compressor and the outdoor unit), at the outdoor coil (gradual micro-leaks), or at the expansion valve. We use an electronic refrigerant leak detector (far more accurate than soap bubbles) to pinpoint the exact location.
Once found, we have options depending on severity and your system's age. A small solder joint leak can be repaired by unsoldering, cleaning, and re-brazing the connection. A coil leak usually means coil replacement (expensive but necessary). We'll present your options honestly and let you decide.
Leak Detection Process
Electronic Detection
EPA-approved leak detection method.
Precise Marking
Leak locations marked for safe repair.
Economic Analysis
Repair vs. replacement evaluation.
EPA Procedures
System evacuation with no venting.
Proper Recharge
Exact refrigerant type and quantity.
Component Repair or Replacement
Once we've identified the problem, repair or replacement happens. Common repairs include contactor replacement (failed relay), capacitor replacement (failed startup component), expansion valve cleaning or replacement (failed flow control), or compressor replacement (failed core component). For each, we source OEM parts when possible—especially for Tempstar systems where we have dealer access.
Installation is always done to manufacturer specs. Electrical work is documented. All work is pressure-tested for refrigerant leaks and performance-tested to verify the fix worked.
Installation Standards
OEM Parts
Original Equipment Manufacturer preferred.
Manufacturer Specs
Installation per wiring diagrams.
Pressure Testing
All refrigerant circuits tested.
Work Documentation
All repairs documented and verified.
Performance Verification & Warranty Documentation
Before we leave your home, we run your system through a complete cooling cycle. We measure pressures again and confirm they match factory specs. We test airflow across all vents and confirm your home is actually cooling. We explain what we fixed, why it failed, and what to watch for going forward. You'll get a detailed invoice, parts documentation, and warranty details for any components we replaced.
If your system is under manufacturer warranty, we'll handle the claim process. If not, we stand behind our labor with a 1-year warranty on all repairs. You have our emergency number and 24/7 access if anything goes wrong.
Before We Leave
Factory Specifications
Refrigerant charge verified to specs.
System Performance
Pressures, temperatures, amperage nominal.
Detailed Work Order
Parts descriptions and labor hours.
Warranty Details
Emergency contact and coverage.
Common AC Repairs We Handle
Refrigerant Leak & Recharge
Low refrigerant is the #1 AC repair. We detect leaks with electronic sensors, repair the connection or component, evacuate the system properly, and recharge to factory specs. Modern refrigerants are environmentally regulated and expensive—we use only approved types and ensure proper charge levels.
Schedule Refrigerant ServiceContactor & Relay Replacement
A failed contactor (the relay that fires up your compressor) makes your AC unresponsive. This is one of the most affordable repairs and usually takes less than an hour. We test electrical continuity to confirm diagnosis, then replace the failed part with an OEM equivalent.
Get Contactor RepairCapacitor Replacement
A blown capacitor (the electrical component that gives your compressor a startup boost) often causes the system to hum but not run. This is an inexpensive fix that we can usually complete in 30 minutes. We use capacitors rated for your exact equipment specs.
Schedule Capacitor ServiceExpansion Valve Repair or Replacement
If the expansion valve (which controls refrigerant flow through the indoor coil) fails or gets clogged, your system can't cool properly. We'll clean it if blockage is the issue, or replace it if internal failure is present. This repair typically takes 1–2 hours depending on access and complexity.
Arrange Expansion Valve ServiceCompressor Repair or Replacement
A compressor failure is the most serious AC repair—and usually the most expensive. We'll diagnose whether the compressor has truly failed (not just tripped on overload), discuss your options (repair is rarely viable; replacement is standard), and walk you through the cost and timeline.
Discuss Compressor OptionsCondenser Coil Cleaning & Repair
Outdoor condenser coils accumulate dust, pollen, and debris over time, reducing cooling efficiency. We clean coils with specialized equipment as part of maintenance. If the coil itself is leaking, we'll discuss repair vs. replacement based on your system's age and value.
Schedule Coil ServiceEvaporator Coil Repair or Replacement
The indoor evaporator coil cools air and pulls humidity from your home. If it freezes over, develops a leak, or accumulates biological growth, cooling suffers. We'll address the underlying cause (usually low airflow or low refrigerant) and repair or replace the coil if necessary.
Get Coil ServiceThermostat Repair or Upgrade
If your thermostat isn't communicating with the outdoor unit or isn't reading temperature accurately, the entire system malfunctions. We'll test, repair, or replace the thermostat—and we can upgrade to a smart or programmable model if you'd like better control and energy savings.
Schedule Thermostat Service
We Repair AC Systems Throughout Des Moines
We provide same-day and emergency AC repair service across the Des Moines metro:
Emergency Service Available In:
Ankeny, IA
North metro Des Moines residents trust us for rapid AC diagnosis and repair. We maintain fast response times and keep common parts in stock to minimize your downtime during peak summer heat.
Urbandale, IA
We repair AC systems throughout northwest Des Moines and Urbandale, serving both established homes and newer construction. Our technicians know the area's housing stock and can handle any system type.
Altoona, IA
Southeast of Des Moines, we provide same-day repair service with emergency availability. We've built strong relationships with Altoona homeowners who rely on us for fast, honest service.
Emergency AC Repair Available
When your AC fails during peak summer heat, we're ready to respond. Call us for same-day or emergency service throughout Greater Des Moines.
Additional Services to Keep Your System Running
Beyond repair, we offer the full comfort solution:
AC Maintenance & Tune-Up
Annual spring and fall tune-ups prevent most repairs before they happen. Join our maintenance plan for automatic scheduling.
Schedule AC MaintenanceHeat Pump Repair
If you have a heat pump system that cools in summer, we repair those as well. Heat pump diagnosis follows the same rigorous process.
Get Heat Pump RepairFurnace Repair & Service
When heating season arrives, we're ready to diagnose and fix furnace problems with the same expertise.
Schedule Furnace RepairIndoor Air Quality Solutions
Improve your home's air with upgrades to filtration, UV purification, and humidity control. Your AC repair might reveal air quality issues we can address.
Improve Your Indoor Air QualityGas Piping Repair
If you have gas-fired heating, we repair and replace gas supply lines and connections safely.
Get Gas Piping ServiceFrequently Asked Questions About AC Repair
Your AC Needs Repair—Let's Fix It Fast
Summer heat waits for no one. When your air conditioner fails, you need a trusted technician who understands the problem, gives you honest answers, and fixes it right the first time. Obsidian Heating and Cooling is ready to diagnose and repair your system today.
We're veteran-owned, Tempstar Elite Dealers, and we've been serving Des Moines, Ankeny, Urbandale, Altoona, Grimes, and Clive for 15 years. When you call, you reach a local business that cares about your comfort and backs up every repair with professional integrity.
