Why Is My Heat Pump Running All the Time?

You just installed a new heat pump. You notice it runs almost constantly - sometimes for hours without stopping. Is this normal? Yes! In fact, it's a sign it's working correctly.

Let me explain why heat pumps behave so differently from traditional systems.

Heat Pumps vs Gas Furnaces: Different Operating Logic

Gas Furnace (Traditional)

• Strategy: Blast hot air (130-140°F) then turn off
• Cycle time: 15-20 minutes on, 15-20 minutes off
• Temperature swing: ±3°F is normal
• Like: Sprinting, then resting, then sprinting again

Modern Heat Pump

• Strategy: Low, slow, continuous heating (90-105°F)
• Cycle time: Runs continuously for hours at low capacity
• Temperature swing: ±0.5°F (very stable)
• Like: Marathon runner at steady pace

When Continuous Running Is NORMAL

✅ Scenario 1: Variable-Speed Heat Pump

Most modern heat pumps are variable-speed, meaning they:

• Run at 25-40% capacity most of the time
• Adjust continuously based on need
• Almost never shut off completely
• This is exactly how they're designed

Bay Area example: Your heat pump might run 20 hours/day in winter, but only at 30% capacity. This is perfect.

✅ Scenario 2: Very Cold or Hot Days

Even single-stage heat pumps will run continuously when:

• Heating: Outdoor temp below 40°F
• Cooling: Outdoor temp above 90°F
• They're working hard to keep up with extreme demand

This is normal and efficient.

✅ Scenario 3: First Time Running

First few days after installation:

• System "learns" your home
• Building up to set temperature for first time
• Might run 24+ hours initially

Give it 3-5 days to settle in.

✅ Scenario 4: Large Temperature Change

Set thermostat from 65°F to 72°F?

• Heat pump will run continuously until reaching target
• Can take 2-4 hours
• Then settles into normal cycling

Why Continuous Running Is Actually BETTER

1. More Efficient

Variable-speed at 30% capacity:

• Uses less energy than on/off cycling
• 20-30% more efficient overall
• Lower electricity bills

2. Better Comfort

Continuous operation:

• No temperature swings
• No "cold blasts" from vents
• Consistent, even warmth

3. Better Air Quality

Air constantly circulating:

• Better filtration
• More even temperature throughout home
• Less dust settling

4. Quieter

Low-speed operation:

• 50-55 dB (whisper quiet)
• vs 70 dB when cycling on/off at full power

5. Longer Equipment Life

Less wear and tear:

• Fewer startups (biggest stress on compressor)
• Steady-state operation easier on components
• 15-20 year lifespan maintained

When Continuous Running Is a PROBLEM ⚠️

❌ Red Flag #1: Can't Reach Set Temperature

Heat pump runs non-stop AND:

• Home never reaches thermostat setting
• Temperature keeps dropping (heating mode)
• Temperature keeps rising (cooling mode)

Possible causes:

• System undersized for your home
• Refrigerant leak
• Faulty thermostat
• Dirty air filter blocking airflow

Action: Call for service

❌ Red Flag #2: Higher Electric Bills

Heat pump runs constantly AND:

• Bill increased 50%+ vs previous system
• Usage spiking vs similar homes

Possible causes:

• Stuck in emergency heat mode
• Faulty compressor (working too hard)
• Duct leaks (losing conditioned air)

Action: Check your bills, call for diagnosis

❌ Red Flag #3: Icing Up (Not During Defrost)

Heat pump runs continuously AND:

• Ice builds up on outdoor unit
• Stays iced for 30+ minutes
• Reduced airflow from vents

Normal: Brief defrost cycles (ice melts within 10 min) Problem: Continuous ice build-up

Action: Call for service

❌ Red Flag #4: Strange Noises

Heat pump runs constantly AND:

• Grinding, squealing, or rattling sounds
• Getting louder over time
• Unusual vibrations

Action: Turn off system, call for service

DIY Troubleshooting Checklist

Before calling for service, check:

1. Air Filter (Most Common Issue!)

• Check: Is filter dirty or clogged?
• Fix: Replace filter
• Impact: Blocked filter = 40% efficiency loss

2. Thermostat Settings

• Check: Mode set to "Heat" or "Cool" (not "Emergency Heat")
• Check: Fan set to "Auto" (not "On")
• Check: Temperature set appropriately

3. Outdoor Unit

• Check: Any obstructions around unit?
• Check: Covered in leaves/debris?
• Clear: 2 feet of clearance all around

4. Vents & Registers

• Check: Are vents open in all rooms?
• Check: Furniture blocking airflow?
• Fix: Open vents, move furniture

5. Defrost Mode

• Watch: Does it cycle into defrost mode?
• Normal: 10-15 minute defrost cycles
• Problem: Never defrosts or constant defrost

Heat Pump Run Time by Bay Area Climate

Coastal Areas (SF, Oakland, Berkeley)

Winter (50-60°F days):

• Variable-speed: 18-22 hours/day at 25-35% capacity
• Single-stage: 8-12 hours/day with frequent cycling

Summer (65-75°F days):

• Variable-speed: 10-14 hours/day at low capacity
• Single-stage: 4-8 hours/day

Inland Valleys (Walnut Creek, Concord, Livermore)

Winter (35-50°F days):

• Variable-speed: 20-24 hours/day at 40-60% capacity
• Single-stage: 14-18 hours/day

Summer (85-95°F days):

• Variable-speed: 16-20 hours/day at 50-70% capacity
• Single-stage: 12-16 hours/day

Comparing Energy Use

Old gas furnace + AC:

• Short cycles, high output
• Annual cost: $1,400

New heat pump (running "constantly"):

• Long cycles, low output
• Annual cost: $900
• Savings: $500/year despite running more

Why? Continuous low-capacity operation beats on/off high-capacity cycling.

What to Tell Your Neighbors

Neighbor: "Your heat pump runs all the time! Something's wrong!"

You: "That's actually how modern heat pumps work. It runs at low capacity continuously instead of blasting hot air on/off. It's more efficient and comfortable - and my bills are lower than yours!"

When to Call Galaxy

Call if:

• Can't reach set temperature for 4+ hours
• Ice staying on unit for 30+ minutes
• Bills spiked dramatically
• Strange noises or smells
• System short-cycling (on/off every 5 min)

Don't call if:

• Heat pump runs most of the day quietly
• Home is comfortable at set temperature
• Bills are normal or lower
• Just different from old furnace

The Bottom Line

For variable-speed heat pumps in the Bay Area:

• Running 18-24 hours/day = NORMAL
• Running at 25-40% capacity = EFFICIENT
• Stable temperatures ±0.5°F = WORKING PERFECTLY

Remember: Gas furnaces sprint. Heat pumps marathon. Both get you to the same place - heat pumps just do it more efficiently.

Questions?

If you're unsure whether your heat pump is running normally, we offer free system check-ups.

Schedule System Check | Call (925) 578-3293