Quick Answer
Okay so here's the quick version. Your heat pump's blowing cold in the winter nine times out of ten because of something simple. First, check your thermostat settings. Is it on 'Heat' or 'Auto' with a sufficiently high setpoint? Ensure 'Emergency Heat' isn't accidentally engaged. Sounds simple, but it's a common oversight. Next, go look at your air filter. If it's clogged solid, that's your problem – poor airflow drastically reduces efficiency and can cause other issues. If it's not those, you might have a frozen outdoor unit (check for thick ice), which indicates a defrost issue. Other problems could be low refrigerant or a faulty component like a capacitor or reversing valve. Simple fixes like a filter cost you maybe $10-$30. Anything else beyond basic thermostat checks or filter replacement, and you're gonna need to call a pro like me, looking at $250 to over a grand, often significantly more for refrigerant leaks or major component replacements.
Common Symptoms
Possible Causes
Step-by-Step Diagnosis
Step 1
Check thermostat settings: Make sure it's set to 'HEAT' and the temperature is set above the current room temp. Check batteries.
Step 2
Inspect the air filter: Check if it's clogged with dust and dirt. Replace if you can't see light through it.
Step 3
Check the circuit breakers: Find the breakers for the 'Air Handler' and 'Condenser' in your electrical panel and see if they are tripped.
Step 4
Examine the outdoor unit: Look for heavy ice buildup (beyond a light frost) and ensure the unit is not blocked by debris, snow, or yard items.
Step 5
Listen to both units: Identify if fans are running, if the compressor is humming, or if there are any unusual sounds like grinding or screeching.
Step 6
For advanced users only: Safely check for power at the unit's contactor and test component ratings like capacitors with a multimeter.
DIY vs Professional Costs
| Repair Type | DIY Cost | Professional Cost | Time Required |
|---|---|---|---|
Replace Air Filter | $10 - $30 | $75 - $150 (as part of a call) | 5 minutes |
Replace a Capacitor | $20 - $50 | $150 - $400 | 1-2 hours (if you're careful) |
Replace Fan Motor | NOT a DIY (part cost only $150 - $300) | $400 - $800 | 2-4 hours |
Replace Defrost Control Board | NOT a DIY (part cost only $100 - $250) | $350 - $700 | 2-3 hours |
Find & Fix Refrigerant Leak | NOT a DIY job | $500 - $2500+ | 3 hours to multiple days |
Replace Reversing Valve | NOT a DIY job | $600 - $1800 | 4-6 hours |
When to Call a Professional Hvac
- The circuit breaker trips repeatedly as soon as you reset it.
- You hear loud, metallic noises like grinding or screeching, which indicates a serious mechanical failure.
- The outdoor unit is encased in a solid block of ice and does not thaw on its own.
- You suspect a refrigerant leak (hissing sounds or oily residue on the copper lines).
- The system won't turn on at all after checking the thermostat and breakers.
- You are not 100% confident in your ability to safely work with high-voltage electricity.
Prevention Tips
- Replace your air filters every 1-3 months. A clean filter is the cheapest insurance for your HVAC system.
- Schedule a professional tune-up every fall before the heating season begins to catch problems early.
- Keep the area around your outdoor unit clear of leaves, grass, bushes, and snow. It needs at least 2 feet of clearance to breathe.
- Gently rinse the outdoor unit's coils with a garden hose in the spring and fall to remove dirt and debris.
Frequently Asked Questions
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