HVAC Emergency Tips: What to Do When Your System Fails

Colorado's climate makes HVAC failures more than just an inconvenience. With winter temperatures dropping below zero and summer heat waves pushing into the 90s, a broken furnace or AC can quickly become dangerous. This guide helps you respond effectively to HVAC emergencies, perform safe troubleshooting, and know when professional help is needed.

Furnace Emergency: No Heat in Winter

When your furnace stops working on a cold Colorado night, time matters. Follow these steps in order:

Step 1: Check the Obvious First

• Thermostat settings: Make sure it's set to "Heat" and the temperature is set higher than the current room temperature
• Thermostat batteries: Many thermostats need batteries; dead batteries = no heat signal
• Thermostat display: If the screen is blank, it's not communicating with your furnace

Step 2: Check Power Sources

• Furnace switch: There's usually a light switch on or near the furnace—make sure it's on
• Circuit breaker: Check your electrical panel for tripped breakers (look for one that's in the middle position)
• Furnace door: Many furnaces have a safety switch that prevents operation if the door isn't fully closed

Step 3: Check the Filter

A severely clogged filter can cause the furnace to overheat and shut down. If your filter looks like a solid gray mat rather than showing any light through it, replace it immediately. This simple fix solves many "emergencies."

Step 4: Check Pilot Light or Ignition (If Accessible)

Older furnaces have standing pilot lights that can blow out. If you're comfortable with it and your furnace has a visible pilot, follow the relighting instructions on the unit. Modern furnaces use electronic ignition—if you hear clicking but no ignition, the igniter may be faulty.

Step 5: Call for Professional Help

If basic troubleshooting doesn't solve the problem within 15-30 minutes, call for service. Describe what you've already checked—this helps technicians prepare and potentially diagnose faster.

Staying Safe Without Heat

If repairs will take time or you're waiting for service, protect your family and home:

Keep People Warm

• Layer clothing and use extra blankets
• Gather family in one room to conserve body heat
• Close doors to unused rooms
• Hang blankets over windows for extra insulation
• Use electric space heaters safely (keep away from anything flammable, never leave unattended)

Prevent Pipe Freezing

• Open cabinet doors under sinks on exterior walls
• Let faucets drip slightly to keep water moving
• If temperature drops significantly, consider draining pipes
• Know where your main water shutoff is located

When to Leave

Consider temporary relocation if:

• Indoor temperature drops below 55°F (risk of pipe freezing increases)
• You have infants, elderly family members, or people with medical conditions
• Repairs won't be completed before nightfall in extreme cold
• You can't safely use supplemental heating

AC Emergency: No Cooling in Summer

While generally less immediately dangerous than no heat, AC failures during Colorado heat waves can be serious, especially for vulnerable individuals.

Step 1: Basic Checks

• Thermostat: Set to "Cool" with temperature below current room temp
• Circuit breakers: Check both the indoor (air handler) and outdoor (condenser) breakers
• Air filter: A clogged filter can cause the system to shut down
• Outdoor unit: Make sure it's running (you should hear the fan)

Step 2: Check the Outdoor Unit

• Look for ice formation (indicates bigger problems—turn system off and let it thaw)
• Clear any debris blocking airflow (leaves, grass clippings)
• Make sure the disconnect switch near the unit is in the "on" position

Step 3: Reset the System

Try turning the system off at the thermostat, waiting 5 minutes, then turning it back on. This can reset electronic controls. If the outdoor unit runs but no cool air comes from vents, the problem may be with the air handler or refrigerant.

Staying Safe Without AC

• Use fans strategically: Box fans in windows (blowing out on the sunny side, in on the shady side) can create airflow
• Close blinds and curtains: Especially on south and west-facing windows
• Stay hydrated: Drink plenty of water even if you don't feel thirsty
• Avoid using the oven: It adds significant heat to your home
• Take cool showers: Helps lower body temperature
• Head to cooling centers: Libraries, malls, and community centers offer relief during heat waves

Warning Signs of Heat-Related Illness

Watch for these symptoms, especially in elderly family members:

• Heavy sweating that suddenly stops
• Confusion or disorientation
• Rapid heartbeat
• Nausea or vomiting
• Hot, dry skin

These can indicate heat exhaustion or heat stroke—seek medical attention immediately.

Carbon Monoxide: The Invisible Emergency

Carbon monoxide (CO) is produced by gas furnaces, water heaters, and other fuel-burning appliances. It's odorless and colorless, making it especially dangerous.

If Your CO Detector Alarms:

1. Don't assume it's a false alarm or dead batteries
2. Get everyone out of the house immediately
3. Leave doors open as you exit (helps ventilate)
4. Call 911 from outside
5. Don't re-enter until emergency responders clear the home
6. Have your furnace and other gas appliances inspected before using them again

CO Poisoning Symptoms:

• Headache
• Dizziness
• Nausea
• Confusion
• Shortness of breath
• Multiple family members feeling sick at the same time

Gas Leak Response

Natural gas has a distinctive "rotten egg" smell added for detection. If you smell gas:

1. Don't turn on/off any switches or lights—sparks can ignite gas
2. Don't use phones inside—even that can create a spark
3. Don't try to find the leak—just get out
4. Leave doors open as you exit
5. Call 911 and your gas company from a safe distance (neighbor's house or down the street)
6. Don't return until professionals clear the home

Preventing HVAC Emergencies

Most HVAC emergencies are preventable with regular maintenance:

• Schedule bi-annual maintenance: Spring for AC, fall for heating
• Change filters regularly: Monthly during heavy use seasons
• Listen for warning signs: Unusual noises, strange smells, or declining performance
• Address problems promptly: Small issues become big emergencies
• Test your system: Run heating and cooling briefly before each season begins
• Keep CO detectors working: Test monthly, replace batteries annually

Frequently Asked Questions