Heating Systems
Your heating system keeps your home comfortable during cold months. Whether you have a gas forced air furnace or a heat pump, understanding how it works and providing regular maintenance ensures efficient operation and extends equipment life.
Check your thermostat or equipment to determine which type of heating system you have - maintenance requirements differ between gas furnaces and heat pumps.
How It Works
Gas Forced Air Systems
A gas furnace burns natural gas to heat air, which is then distributed through ductwork to your rooms. The thermostat controls when the furnace cycles on and off.
Key components:
- Furnace - Burns gas to heat air
- Blower - Circulates air through ducts
- Thermostat - Controls temperature
- Filter - Cleans circulating air
- Ductwork - Distributes heated air
Heat Pump Systems
A heat pump uses refrigerant to transfer heat from outside air into your home. The same unit provides both heating AND cooling. An auxiliary (backup) heat system supplements during extremely cold weather.
Key difference: Air from vents feels cooler than with a gas furnace - this is normal. Heat pumps operate at lower temperatures but run longer cycles.
Key components:
- Outdoor unit - Extracts heat from outside air
- Indoor unit - Distributes heated air
- Reversing valve - Switches between heating and cooling
- Auxiliary heat - Electric backup for cold weather
- Defrost cycle - Removes ice from outdoor coils
Routine Maintenance
| Task | Frequency | Time Required |
|---|---|---|
| Check/replace air filter | Monthly | 5 minutes |
| Clear debris from outdoor unit (heat pump) | Monthly | 10 minutes |
| Check that vents are open | Seasonally | 5 minutes |
| Test system before heating season | Annually (fall) | 15 minutes |
| Professional maintenance | Annually | N/A |
Air Filters (Critical!)
A clean filter is one of the most important maintenance tasks.
Frequency: Monthly during heating season (year-round if you have AC too)
Why it matters:
- Dirty filter reduces airflow and efficiency
- Can cause cold spots in your home
- Can freeze air conditioning coils
- Reduces equipment lifespan
Permanent filters: If you have a washable filter, clean monthly following manufacturer instructions.
Outdoor Unit Care (Heat Pump)
Keep the outdoor unit clear of:
- Snow and ice
- Leaves and debris
- Landscaping materials
- Trash or stored items
Snow or ice blocking the unit causes serious efficiency problems.
Vent Adjustments
Experiment with adjustable registers for best heat flow:
- Reduce heat to seldom-used or interior rooms
- Keep vents near windows unobstructed to minimize condensation
- Keep window coverings slightly open in cold weather
- Ensure return air vents are not blocked by furniture
Troubleshooting
Gas Furnace Not Heating?
Quick Checklist:
- Thermostat is set to "heat" and temperature is set above room temperature
- Blower panel cover is installed correctly (has safety switch)
- Breaker on electrical panel is ON
- On/off switch on side of furnace is ON
- Gas line is open at main meter AND at furnace
- Filter is clean and allowing airflow
- Vents in rooms are open
- Air returns are unobstructed
- Exterior exhaust vents are not blocked by snow or ice
If you smell gas, leave the home immediately and call the gas company. Do not flip switches or create sparks.
Heat Pump Not Heating?
Quick Checklist:
- Thermostat is set to "heat" and temperature is set above room temperature
- Breaker on main electrical panel is ON
- Filter is clean and allowing airflow
- Vents in rooms are open
- Air returns are unobstructed
- Outside unit is not blocked by snow, ice, or debris
- Outside coil is not clogged with snow or ice
Auxiliary heat stays on? If the auxiliary heat light stays on when outside temperature is above 30°F, contact a service technician.
Temperature Variations Between Rooms
Temperatures vary from room to room and floor to floor by several degrees. This is normal and due to:
- Floor plan and room orientation
- Number and size of windows
- Window coverings usage
- Open or closed interior doors
- Heat rising to upper floors
Try this:
- Open vents in rooms you use most
- Partially close vents in unused rooms
- Run furnace fan continuously for better air mixing
- Readjust when seasons change
What to Avoid
Do not overheat your new home, especially in the first year. Overheating causes excessive shrinkage of framing lumber and may damage the home.
- Don't block vents or returns - Restricts airflow and reduces efficiency
- Don't set thermostat extremely high - Won't heat faster, wastes energy
- Don't ignore dirty filters - Causes system strain and potential damage
- Don't close more than one vent completely (heat pump) - Restricts airflow too much
Heat Pump Specific
- Don't make large thermostat changes - Adjust no more than 2°F at a time
- Don't turn down thermostat at night (unless you have a heat pump-specific setback thermostat)
- Don't have another firm modify the system during warranty - voids that portion of warranty
Understanding Normal Behaviors
Initial odor: A new furnace may emit an odor when first used, or after being unused. This is from manufacturing oils and dust in the ducts and passes quickly.
Duct noise: Some popping or pinging sounds are normal as ductwork heats and cools during operation.
Defrost cycle (heat pump): During heating, outdoor coils can freeze. The system automatically defrosts:
- Outside fan stops temporarily
- Airflow may feel slightly cooler
- Cycle lasts up to 10 minutes
- Can only occur once every 90 minutes
This is completely normal automatic operation.
Programmable Thermostat Settings
Your home may include a smart thermostat with features designed to optimize comfort and efficiency. Understanding these settings helps you get the most from your heating system.
Heat Pump Systems
Heat pumps require different thermostat strategies than gas furnaces. If your home has a heat pump, follow these guidelines.
Temperature Setback Guidelines
Unlike gas furnaces, heat pumps work most efficiently with consistent temperatures. Large setbacks trigger expensive auxiliary heat when recovering.
Best practice: Keep temperature adjustments within 2-4°F of your normal setting. This maintains comfort while avoiding auxiliary heat activation.
Recommended Nest Settings
If your home has a Nest thermostat, it includes Heat Pump Balance modes. We recommend keeping the default settings:
| Setting | Recommended Value | Purpose |
|---|---|---|
| Heat Pump Balance | Balanced (default) | Optimizes comfort and efficiency |
| Auxiliary Lockout Temperature | 40°F | Prevents aux heat above this outdoor temp |
| Compressor Lockout Temperature | 0°F | Prevents compressor damage in extreme cold |
What these settings achieve:
- Heat pump handles most heating needs efficiently
- Auxiliary heat activates only when necessary (below 40°F outdoors)
- System protected from damage in extreme cold
Alternative Balance Modes
Your Nest offers two other modes depending on your priorities:
Max Savings Mode
- Prioritizes electric efficiency over comfort
- Heat pump runs longer before auxiliary heat activates
- Best for: Households focused on minimizing electric bills
- Trade-off: Slower temperature recovery on very cold days
Max Comfort Mode
- Prioritizes reaching set temperature quickly
- Auxiliary heat activates sooner
- Best for: Households that need higher temperatures or faster recovery
- Trade-off: Higher electric bills during cold weather
Understanding Backup Heat Costs
Electric resistance backup heat costs significantly more than heat pump operation. If you notice the "Aux Heat" indicator frequently active when outdoor temperatures are above 40°F, contact warranty service.
The auxiliary heat light on your thermostat indicates when backup heat is running. This is normal in very cold weather but should not activate frequently on mild days.
Additional Thermostat Features
Farsight Display: When connected to WiFi, your Nest can display the current temperature, weather, or time when you approach it. This feature requires an active WiFi connection.
Defrost Management: Your Nest automatically manages defrost cycles - no adjustment needed. See "Understanding Normal Behaviors" above for what to expect during defrost.
Seasonal Care
Before Winter
- Replace air filter
- Test system on a mild day
- Clear debris from outdoor unit (heat pump)
- Check that all vents are open
- Schedule professional maintenance if due
During Winter
- Check filter monthly
- Keep outdoor unit clear of snow (heat pump)
- Monitor for unusual sounds or odors
- Keep exterior exhaust vents clear
Related Topics
Warranty Coverage: See Heating: Gas Forced Air Standards or Heating: Heat Pump Standards for coverage periods and exclusions.