Home Furnaces Guide

How to Buy & Maintain Your Home Furnace

A furnace is one of the most important systems in your home, providing essential warmth throughout Wisconsin’s cold winters. Whether you're buying a new furnace or maintaining an existing one, our guide will help you get the most out of your home's heating. Our heating and furnace experts are ready to diagnose, repair or replace your furnace! Contact us to get started.

Call now: 414-534-1619Contact us online

Table of Contents

Buying a Home Furnace
Home Furnace Maintenance Info
Fixing vs. Replace a Home Furnace
Milwaukee Furnace Service

Furnace Buying Guide

What is a Home Furnace?

A home furnace is a heating system designed to generate and distribute warmth within a residential space. Powered by natural gas, oil, electricity or propane, furnaces work by heating air and then circulating it through ducts to various rooms in a house. The heating process is controlled by a thermostat, allowing residents to set and maintain their desired indoor temperature. The typical temperature range falls between 68 and 75 degrees Fahrenheit for homes in Wisconsin. Furnaces are a common central heating option in many homes, providing efficient and reliable warmth during colder seasons.

How Does a Home Furnace Work?

Behind the scenes, your home's gas furnace relies on a carefully orchestrated series of automated steps to deliver heated air. When the thermostat signals a need for heat, the furnace initiates an ignition sequence and safely lights the burner. High-temperature flue gasses are then produced.

A blower fan pushes room-temperature air over the hot heat exchanger containing the gas burner flames. This process transfers heat to the circulating air, which is carried through ductwork to warm your home. The furnace monitors conditions, makes adjustments and repeats the cycle to maintain your comfort settings.

11 Steps Your Furnaces Takes to Heat Your Home

1. The thermostat senses the temperature has dropped below the set point and sends a signal to the furnace to turn on.
2. The draft inducer fan turns on and ventilates the furnace, preparing for heating.
3. The hot surface igniter heats up to ignite the gas burner.
4. The gas valve opens to allow natural gas or propane to flow into the burner.
5. The burner ignites and combusts the gas, producing heat.
6. The blower fan turns on and pushes air over the hot heat exchanger containing the burner flames.
7. Air circulates through ductwork and vents, carrying heat throughout the home.
8. The air returns to the furnace through cold air return ducts and filters.
9. The thermostat senses the home has reached the desired temperature and sends a signal to the gas valve to stop the gas flow, extinguishing the flame.
10. The draft inducer fan vents any remaining exhaust gasses and the blower fan turns off once residual heat is removed from the exchanger.
11. The furnace remains idle until the next call for heat from the thermostat, and the cycle repeats.

Types of Home Furnaces

The most common options for homes are gas and electric furnaces, or heat pumps in warmer regions. High-efficiency and smart models are popular new upgrades providing added capabilities and energy savings.

Furnace Type	Fuel Source	Climate Suitability	Efficiency Rating	Special Features
Gas Furnaces	Natural Gas or Propane	All Climates	Common, diverse models	Common, diverse models
Electric Furnaces	Electricity	Milder Climates or Backup Heat	Varies	Simpler system, less common
Oil Furnaces	Oil	Limited Natural Gas Areas	Varies	Requires fuel oil tank, more maintenance
Heat Pumps	Electricity	Best in Milder Climates	High	Efficient heat transfer between indoor and outdoor air
High-Efficiency Furnaces	Gas or Electric	All Climates	Above 80% AFUR	Condensing and modulating models
Smart Furnaces	Gas or Electric	All Climates	Varies	Wifi connectivity, smart thermostat, remote monitoring

How to Find the Right Size Furnace for Your Home

Choosing the optimal furnace size for your home is crucial for comfort and efficiency. An oversized furnace cycles on and off frequently, reducing the system's lifespan. An undersized furnace can't maintain desired temps.

To choose the right sized furnace, an HVAC pro calculates your home's heating load - the BTUs needed to heat the space. Factors include climate, home size, insulation, window efficiency and other heat loss variables. The load analysis indicates the appropriate furnace output capacity for your needs. High-efficiency variable speed and modulating furnaces provide some leeway to handle spikes in demand. Installers also evaluate ductwork to ensure it can handle the increased airflow of a bigger furnace. With the right furnace size, your system runs efficiently for years of comfortable heating.

• Small Homes or Apartments (500-1,000 sq. ft.): Compact living spaces typically require furnaces with lower heating capacities, ranging from 40,000 to 60,000 BTUs (British Thermal Units).
• Medium-Sized Homes (1,000-1,500 sq. ft.): For mid-sized residences, furnaces in the range of 60,000 to 80,000 BTUs should provide efficient heating.
• Average-Sized Homes (1,500-2,500 sq. ft.): Homes of moderate size often benefit from furnaces with capacities between 80,000 and 100,000 BTUs.
• Large Homes (2,500 sq. ft. and above): Larger homes necessitate higher-capacity furnaces, typically ranging from 100,000 to 150,000 BTUs, depending on insulation and climate conditions.

Common Desirable Furnace Features

Choosing a furnace with high AFUE, variable-speed blowers, smart technology, multi-stage heating and sealed combustion ensures energy efficiency, precise control, advanced diagnostics and enhanced safety.

• High AFUE ratings for energy efficiency
• Variable-speed blowers for enhanced temperature control and air circulation
• Smart technology for remote control and advanced diagnostics
• Multi-stage heating options for precise adjustments
• Sealed combustion systems for enhanced safety

How to Balance Furnace Features with Budget

When it comes to selecting a furnace within budget, it's essential to gather the following information to make a well-informed decision.

Start by obtaining multiple quotes from contractors, allowing you to compare and find competitive pricing. Clearly define your must-have features, such as the AFUE rating and fuel type, while being aware that additional features like multi-stage compressors and modulating burners may increase costs.

Consider the lifespan of the furnace, as higher efficiency and variable-capacity options often offset added costs through energy savings over 10-15 years of use. Opt for furnaces with 10-year or lifetime parts warranties to safeguard your investment, and consider scheduling installations in the off-season for potential discounts from contractors. Explore available incentives, such as rebates from local utilities and governments, to offset higher-end system costs. Take advantage of financing options with low APR offered by many contractors, allowing you to spread costs over time.

Prioritize a quality installation, even if it means a slightly higher upfront cost, to prevent future issues and ensure contractor expertise.

Renting vs. Buying a Home Furnace

Choosing between renting and buying a home furnace involves considering upfront costs, maintenance and long-term benefits. Renting offers lower initial expenses and includes maintenance, suitable for those with budget constraints or uncertain about their stay. Buying provides ownership benefits, allowing equity build-up and customization options for long-term cost savings. The decision hinges on individual preferences, financial considerations and the duration of home occupancy.

Furnace Maintenance Guide

When Should I Have My Furnace Serviced?

Regular maintenance is crucial for all furnace types to ensure optimal performance, energy efficiency and to catch potential issues before they become major problems. Always refer to the manufacturer's recommendations and consult with a professional HVAC technician for personalized advice.

Furnace Type	Maintenance Schedule
Gas Furnaces	Annually, preferably before the heating season.
Electric Furnaces	Annually, before the colder months for optimal performance
Oil Furnaces	Annually, ideally before the winter for peak efficiency
Heat Pumps	Bi-annual maintenance, once before the heating season and once before the cooling season
High-Efficiency	Annually, before winter, to ensure efficient operation.
Smart Furnaces	Annually, before winter, to check both mechanical and digital components.

Benefits of Regular Furnace Maintenance

Regular furnace maintenance offers a myriad of benefits, ensuring optimal performance, energy efficiency, safety and longevity.

• Optimal Performance
• Energy Efficiency
• Extended Lifespan
• Improved Safety
• Cost Savings
• Enhanced Comfort
• Manufacturer Warranty Compliance
• Reduced Breakdowns
• Air Quality Improvement
• Compliance with Local Regulations

Can I Inspect My Furnace Myself?

While DIY inspections help spot obvious issues, have an HVAC professional perform comprehensive annual tune-ups to fully evaluate internal components and identify problems early. Professionals have the tools and expertise to diagnose underlying faults. Here are some tips on inspecting your home furnace yourself:

• Check the furnace filter - Dirty filters should be replaced to maximize airflow.
• Look for debris buildup - Dust, dirt, and lint will clog components over time. Gently vacuum accessible areas.
• Inspect the burner - Turn the furnace on and look for bright blue flames without yellow tipping, indicating proper gas combustion.
• Listen for unusual sounds - Banging, grinding or high-pitched whistles can signify failing parts.
• Look for rust and leaks - Rust around the heat exchanger may indicate a leak; oil leaks need immediate attention.
• Check exhaust vent pipe - Ensure piping is intact, attached properly, and with no blockages.
• Monitor cycling times - Extremely short cycles may indicate improper sizing; long run times can signal underperformance.
• Check control panel codes - Reference your model for diagnostic codes signaling specific issues.
• Verify carbon monoxide and smoke detectors are working - Critical safety precautions when doing your basic inspection.

What are Common Furnace Problems?

Common furnace problems include issues with the thermostat, dirty or clogged filters, ignition problems, malfunctioning pilot lights, wear and tear on components, airflow problems and issues with the blower motor or fan. Regular maintenance and prompt professional attention help address any issues and ensure the efficient operation of your furnace.

7 Common Issues and Clear Signs of Trouble

1. Thermostat Issues:
Signs: Inaccurate temperature readings, unresponsive controls or inconsistent heating.
2. Dirty or Clogged Filters:
Signs: Reduced airflow, increased energy bills, uneven heating or visible dust around vents.
3. Ignition Problems:
Signs: Difficulty starting the furnace, frequent cycling or intermittent heat.
4. Malfunctioning Pilot Lights:
Signs: Pilot light goes out frequently, or the flame is yellow instead of blue.
5. Wear and Tear on Components:
Signs: Unusual noises such as banging or squealing, indicating potential issues with blower motors, belts or other internal components.
6. Airflow Problems:
Signs: Insufficient heating, uneven temperature distribution or weak airflow from vents.
7. Issues with the Blower Motor or Fan:
Signs: Weak or no airflow, unusual noises from the blower or inconsistent heating.

What are Furnace Tune-Ups?

Furnace tune-ups are thorough inspections and maintenance services provided by HVAC professionals to ensure efficient and safe heating operation. This includes cleaning, checking for wear, inspecting the thermostat, lubricating moving parts, tightening connections, testing safety controls and addressing potential issues. Regular tune-ups enhance performance, energy efficiency and prevent unexpected breakdowns, promoting the longevity of the heating system.

Common Furnace Tune-Up Items

Common furnace tune-up items include cleaning and inspecting burners for debris and wear, as well as replacing air filters to maintain optimal airflow and system efficiency, ensuring improved performance and longevity. Lubrication of moving parts, such as the blower motor, is essential to prevent friction and ensure smooth operation during the heating season.

Fixing an Old Furnace vs. Buying a New Unit

Navigating the decision between fixing an old furnace and investing in a new unit is a critical aspect of home heating management. The following comparison chart outlines key criteria, including the age of the furnace, repair costs, energy efficiency, performance, operating costs and environmental impact, offering a comprehensive guide to assist homeowners in determining whether to pursue repairs or opt for the purchase of a new, more efficient heating unit.

Criteria	Fixing an Old Furnace	Buying a New Unit
Age of Furnace	Relatively young and in good condition	Outdated or nearing the end of its lifespan
Repair Costs	Cost-effective repair	Significant repair costs or frequent issues
Energy Efficiency	May not meet current standards	Opportunity for higher energy efficiency with a new unit
Performance	Adequate performance after repair	Improved and more reliable performance with a new unit
Operating Costs	May have higher ongoing operating costs	Potential for lower operating costs with a new, energy-efficient unit
Lifespan Expectancy	Short-term solution	Long-term investment with a new unit
Environmental Impact	Continued use of an existing unit	Potential for a more environmentally friendly option with a new, efficient unit
Upfront Investment	Lower upfront cost for repairs	Higher initial investment for a new unit
Long-Term Savings	Limited potential for long-term savings	Potential for energy savings and reduced maintenance costs over time with a new unit

3 Common Signs Your Furnace is Going Out

Strange furnace noises (banging, humming or screeching), inadequate heating and a burning smell signal potential issues. If you notice any of the following, it may be time to replace your furnace!

1. Noisy operation - If your furnace is making strange noises like banging, humming or screeching, it could indicate a problem. Noises are a sign of loose parts or components failing inside the furnace.
2. Not heating up properly - If your home is taking longer to get warm or certain rooms aren't heating well, your furnace may not be operating at full capacity. Insufficient heating is a clue that the furnace needs repair.
3. Burning smell - An unusual burning odor from the furnace likely means something is overheating or rubbing where it shouldn't be inside the unit. This could lead to serious issues if not addressed.

When to Fix a Furnace

If your furnace is less than 15 years old, it can be worth fixing minor problems as they emerge. Replacing the ignitor, fan limit switch or thermostat is cheaper than a brand-new furnace, but be watchful for signs of major component failure. If the core functions of your middle-aged furnace start needing significant repairs, it's smarter to put that money toward a new one for improved longevity and efficiency. Evaluate repair costs versus replacement costs when deciding.

When to Buy a New Furnace

If your furnace is more than 15 years old, it's typically better to replace the entire unit than continue fixing issues as they arise. Older furnaces are less energy efficient, have more wear and tear and finding replacement parts is difficult. You'll likely save money over the long run by investing in a new, warrantied furnace with modern efficiency standards. This is especially true if your current furnace requires major repairs like a heat exchanger or blower motor replacement.

Prompt Heating is Milwaukee’s Premier Home Furnace Company

Prompt Heating stands as a premier home furnace company, proudly serving Brookfield, Brown Deer, Delafield, Hartford, Hartland, Menomonee Falls, Mequon, Milwaukee, Muskego, Nashotah, Pewaukee, Sussex, Waukesha, Wauwatosa, West Allis and the surrounding communities of Southeast Wisconsin. We take pride in our strong customer reviews, reflecting our commitment to providing expert furnace services.