Heat Pump Blowing Cold Air in Dallas? What's Normal vs. What Needs Repair

Heat pump air feels different than furnace air, and understanding this difference prevents unnecessary service calls. This guide from Dallas Heating and Air Conditioning explains normal heat pump behavior and helps you identify actual problems requiring professional heating repair.

Is It Really Cold Air? Temperature Reality Check

Heat pump supply air is typically 85-95°F. Furnace supply air is typically 120-140°F. This is critical to understand because heat pump air at 90°F feels lukewarm or even cool against your skin (your body is 98.6°F). This is normal physics, not a malfunction.

To verify your heat pump works correctly, hold a thermometer in front of a supply vent. If the air is 85-95°F and your room temperature is rising (even slowly), your heat pump is working normally. If the air is below 80°F or the same as room temperature, continue troubleshooting.

Normal Heat Pump Behaviors

Defrost cycles are normal and necessary. Your heat pump periodically reverses to melt ice on the outdoor coil, briefly running like an air conditioner. You'll notice cool air for 5-10 minutes, steam rising from the outdoor unit, and the outdoor fan may stop temporarily. Normal heating resumes after defrost completes.

DIY Checks for Actual Problems

Thermostat Settings

Verify the mode is set to HEAT (not Cool, Auto, or Off). Some systems have separate "Heat Pump" and "Emergency Heat" modes. If set to "Emergency Heat," only backup strips run (no heat pump), which provides heat but is expensive. Switch back to normal HEAT mode.

Air Filter and Outdoor Unit

Replace a dirty air filter because restricted airflow reduces heating efficiency and can cause the system to ice up. Check that the outdoor unit is clear of leaves, debris, and overgrown plants. Trim vegetation back to 2 feet of clearance and gently hose off coils if visibly dirty (don't use a pressure washer).

Professional Repairs for Heat Pumps

Refrigerant Leak or Low Charge

Heat pumps use refrigerant to move heat, so low refrigerant means reduced heating capacity. Signs include gradual decline in heating performance, ice on the outdoor unit or refrigerant lines, and the system running constantly but not heating well.

Refrigerant handling requires certification, and the technician must find and fix the leak (not just add refrigerant). Improper charge damages the compressor. Repair costs $400-$1,200 depending on the leak location.

Reversing Valve Stuck or Failed

The reversing valve switches between heating and cooling. If stuck in cooling mode, your system cools instead of heats, producing genuinely cold air in heating mode. You'll notice cold air (actually cooling) when set to heat, the system works fine in cooling but not heating, or you may hear clicking when trying to switch modes.

This requires refrigerant system work and may need valve replacement. Repair costs $400-$900.

Defrost System Failure

When the defrost system doesn't activate when needed, ice builds up and blocks the outdoor coil. Your system can't absorb heat. Signs include heavy ice buildup that doesn't clear, defrost cycles that never seem to run, and continuous operation with declining performance.

The problem could be the defrost board, sensor, or reversing valve. Letting it continue causes damage. Repair costs $300-$700.

Auxiliary Heat Not Working

When the heat pump alone can't keep up during very cold weather, backup heat should activate. If backup isn't working, your house stays cold on the coldest days. Your house is comfortable on mild days but cold when temperatures drop, the heat pump runs constantly but can't maintain temperature, and emergency heat mode doesn't provide more heat.

DFW temperature swings stress heat pumps, making functional auxiliary heat essential during cold snaps. Repair costs $200-$600 depending on whether it's heat strips, sequencer, or wiring.

When to Call for Service

Call Dallas Heating and Air Conditioning at (214) 710-2515 if your outdoor unit is heavily iced and not clearing, supply air is genuinely cold (not just less warm), or you've checked the filter and thermostat with no improvement. We serve Dallas, Plano, Frisco, McKinney, Allen, Richardson, Carrollton, The Colony, and Lewisville with same-day service available.

Our EPA-certified technicians have over 20 years serving North Texas and understand how temperature swings stress heat pumps. We're experienced with the unique challenges of heat pump operation in our climate.