How To Install A Furnace? Step-By-Step Setup Guide

In this blog post, we will understand the detailed process of how to install a furnace and the factors affecting its installation in detail.

How To Install A Furnace?

how to install a furnace

To complete the furnace installation process with proper guidance and without wasting additional time, positioning and leveling the furnace unit, connecting gas and electricity lines, and commissioning and testing the furnace unit are the key steps to follow. 

These steps should be performed with caution and with emphasis on safety measures.

Positioning and leveling the furnace unit

When installing a furnace, precision, and detail are key. 

Here’s how to do it:

  1. Check local codes and regulations.
  2. Clear the area of debris.
  3. Put the furnace on a sturdy base. 
  4. Use shims as needed for balance.
  5. Adjust the leveling feet until stable.
  6. Check connections before continuing.

Connecting gas and electricity lines

It’s time to get your gas and power lines hooked up for installation.

Here’s a 4-step guide:

Turn off the gas supply and disconnect your old appliance if you’re replacing it.
Connect the flexible hose from the new appliance to the gas supply pipe tightly, to avoid leakage.
Connect the appliance to an electrical outlet with a 3-pronged plug, or wire it directly to avoid overheating.
Test both connections carefully with soapy water for gas leaks before turning power back on.

Commissioning and testing the furnace unit

The installation of the furnace unit is just the first step. To ensure it runs efficiently and safely, it must be commissioned and tested regularly. 

Here are the steps:

  1. Read the manufacturer’s instructions.
  2. Check all electrical connections.
  3. Look out for gas piping damage or leaks.
  4. Observe how the furnace starts.
  5. Measure temperature setpoints versus actual temperature.
  6. Clean or replace filters.

Factors to consider before the installation process

To ensure a smooth furnace installation process, you need to consider several factors before starting the actual installation. 

In this section, we will focus on these factors that you will encounter.

The size and type of the furnace unit needed

Size and type of the furnace unit are important to consider before installing. It’s important to choose the right unit that offers sufficient heating and the highest efficiency for the space. 

Criteria like house size, insulation level, climate, and number of occupants should be taken into account. 

Additionally, check if the ductwork can handle the furnace’s airflow needs and if any modifications are needed in the vents for a proper connection. 

It’s best to consult an HVAC expert to assess all the details and recommend a suitable size and type. 

Lastly, ensure your gas and electric supply are sufficient before installation.

Gas and electric supply requirements

Before installing, consider the necessities for gas and electricity. Check if the location has access to a suitable gas supply, like natural or propane. 

Simultaneously, make sure the electrical system can handle power needs.

It’s important to follow safety regulations set by authorities. Ensure the area around gas refueling is well-ventilated and free of combustible material. 

Plus, inspect wiring to comply with local building codes.

Evaluate risks to prevent surprises when using the appliance. Pay attention to fuel supply needs otherwise, you risk harm and damage. 

Review installation procedures carefully for a safe and efficient home.

Thermostat and filtration system

Climate control and air cleaning are key for a comfy indoor environment. 

Here are some important points to ponder before setting up the temperature regulator and filtration system in your abode or office.

Plus, make sure you buy temperature regulators that mesh with your HVAC system’s power needs to conserve energy and upgrade performance effectively.

Cold spots and ductwork inspection

  • Ventilation and inspection of air ducts are extremely important before installation. 
  • Do temperature checks to make sure there are no cold zones. 
  • Inspect ductwork for any errors or leaks that can block airflow. 
  • Fixing these problems guarantees great performance and energy savings.
  • Air duct cleaning is a must before installation. 
  • Clogged ducts slow down airflow and affect performance.
  • Keep up with your maintenance schedule. 
  • Regularly clean and inspect the system for longer life and reduced maintenance costs.

Difference Between Thermostat System And Filtration System

The following table represents difference between thermostat system and filtration system:

The ThermostatThe Filtration System 
Get a model with a programmable function that goes with your daily routine.Select an air filter type that matches your health needs (e.g., HEPA, activated carbon).
Place the regulator away from direct sunlight, draughts and heat-emitting appliances.Change the filters as per maker’s instructions to sustain ideal performance.
Calibrate the thermostat for precise temperature sensing, placement, and battery levels often.Plan routine checkups by certified technicians to ensure proper air circulation across your place.

Preparation before the actual installation

It includes checking out the installation area and making sure you have the necessary permits. 

To prepare for a smooth furnace installation with the subsections of getting necessary permits, clearing out the installation area, orienting the furnace unit, and making alterations as needed, you need to focus on several important factors. 

Getting necessary permits

It’s essential to get permission from the authorities before continuing with the installation. 

The permit required will vary depending on the geographic location and regulations. 

Certain devices or equipment will need electrical, zoning, or building code permits. Not having the right permits can lead to legal and financial issues.

It’s important to plan ahead as permits can take a while. The National Association of Home Builders Research Center says 30% of all projects are delayed because of permit problems.

Before starting the installation, check for any unwanted guests in the walls  mice can cause major home improvement problems.

Clearing out the installation area

For perfect installation, it’s necessary to clear the obstacles. Make a space that is clear and safe for the installers to work quickly and correctly. 

Here are three steps to follow:

  1. Remove furniture or equipment that could block movement during installation.
  2. Clean the area well to avoid risks and delays.
  3. Tuck away loose cables and wires; they can be dangerous if left out.

Orienting the furnace unit

When installing a furnace, it’s key to orient it correctly. This is for optimal performance and longevity. 

Follow these 3 steps:

  1. Identify the spot & make sure it meets code.
  2. Put the furnace in & mark vents/ductwork.
  3. Leave space around for maintenance.
  4. Check accessibility & clearances from combustibles. 

Making alterations as needed

To ensure a seamless install experience, it’s essential to prep the area. 

Here’s how:

1)Inspect the area and identify possible obstacles.
2)Take measurements to avoid surprises.
3)Have your tools handy.
4)Uncover and repair any hidden issues like mold, leaks, or structural problems.
5)Adapt electrical points if needed.

Professional assistance and DIY approaches

To ensure a successful furnace installation for your home, you need to decide whether to seek professional assistance or opt for a DIY approach. 

Hiring an expert installer

When searching for a professional to help with installation, selecting an experienced and reputable installer is key. 

Here are three tips to keep in mind when hiring a skillful installer:

  • Look up credentials and reviews of potential installers online or through word-of-mouth.
  • Check if the installer has the right licenses, insurance and safety certifications for quality work.
  • Meet the installer in person to discuss project details, timeline and budget.

DIY installation by the homeowner

Homeowners can save money by opting for a self-installed home renovation project. 

DIY installation avoids paying for professional help. But, to ensure success, careful consideration of factors is needed.

Follow this 3-Step guide for DIY home installation:

PlanningDecide what project to take up. Create a plan with tasks, tools, equipment, materials, and safety measures.
Gathering ResourcesGet the materials, tools, and equipment earlier. This prevents hiccups during implementation.

Carrying out Installation
Strictly adhere to safety instructions and manufacturer’s guidelines. This ensures safety and durability.

Cost comparison of both approaches

Professional help is pricey due to high labor costs. But, equipment costs are included and outcomes are guaranteed. 

DIY is cheaper labor-wise but you’ll have to pay separately for gear.

ExpensesProfessional AssistanceDIY Approach
Labor CostsHighLow
Equipment CostsIncluded in Service FeesSeparate charges may apply
Time CostMinimalExtensive
Result GuaranteeYesNo

Safety precautions to be taken during the installation of the furnace

To ensure a safe furnace installation process, you need to take adequate safety measures. 

Installing a furnace involves handling gas lines and combustion air, wearing protective gear, and using appropriate tools. 

It’s essential to follow proper safety precautions and not compromise on the safety of yourself or anyone around you. 

Proper handling of gas lines and combustion air

When dealing with gas and combustion, safety must come first. 

Strict guidelines must be followed according to industry standards and regulations. 

  • Fuel piping and air supply must be handled properly.
  • Any mishandling can lead to dangerous leaks or buildups. 
  • Before commencing work, check the area’s schematics for the best route for the pipes. 
  • Connections must be secure and sealed.
  • Ensure there is enough space around natural gas appliances, like furnaces or boilers, for healthy airflow. 
  • Vent gasses properly, especially CO fumes, which can be deadly when inhaled at high concentrations. 

Wearing protective gear and using appropriate tools

Safety is key when installing equipment. 

Here’s what to keep in mind:

  • Wear goggles or face shields when dealing with chips, dust, or flying objects.
  • Use respirators when handling chemicals or dust.
  • Gloves are essential for sharp-edged materials or hazardous substances.
  • Put on sturdy shoes when laying tiles or flooring.
  • Always use the right tool and don’t operate it if it’s damaged.

According to The U.S. Bureau of Labor Statistics, 15% of workplace injuries are caused by incorrect use of protective gear.

Testing the furnace unit after installation

For everyone’s safety, it’s important to test the furnace unit after installation. 

 Here are the steps:

  1. Turn off power at the breaker box.
  2. Check that wire connections are tight and secure.
  3. Run diagnostics with multimeter or other tools, as instructed by the manufacturer.
  4. Run a trial watch for any abnormalities or warning signs and be ready to shut down if necessary.

Post-installation considerations

It’s essential to conduct proper airflow and ventilation inspections, replace old furnace systems, and take steps to boost energy efficiency and save on costs.

Airflow and ventilation inspection

Ventilation is key for your system’s performance. Conducting an Air Quality and Flow Assessment ensures the air is up to industry-standard safety requirements. 

This assessment looks at things like system adequacy, airflow direction, and fresh air exchange rate. Regulations must be met to avoid any health issues.

To keep proper airflow, you need to: clear ducts, install HVAC filters, and ensure insulation in all air conditioning parts. 

Maintenance checks are also important to lengthen the lifespan of ventilation systems.

It’s wise to get professional help when inspecting air circulation and conditioning. This allows for expert advice and detailed records about any faults. 

This makes it easier to increase energy efficiency with minimal disruption to everyday life.

Replacing old furnace systems

Replacing an old heating system is essential. If your furnace has been around for too long or keeps breaking down, it’s time for a change.

Here are the steps:

  1. Choose the fuel – gas, propane, or oil.
  2. Find the size of your new furnace
  3. Consult a technician if you need help.
  4. Pick energy-efficient models that fit your budget. 
  5. Get a high AFUE rating. 
  6. Hire a licensed and insured HVAC contractor to install it.
  7. Do routine maintenance every year for good efficiency.

Energy efficiency and cost-saving measures 

Creating an efficient and cost-saving environment is key. After set-up, consider smart tech and insulation. Smart home automation can cut energy use and costs. 

Households and businesses can save on bills with these measures.

Switch to LED light bulbs instead of traditional ones. These are more energy-efficient and last longer. 

Plus, installing occupancy sensors can reduce lighting and lower electricity bills.

Make sure appliances are Energy Star certified. Check that cooling and heating systems are working before turning them on, so regular maintenance is a must.

Not implementing these steps could mean missing out on savings. Thus, take extra steps for increased efficiency.


Getting permits, changing ductwork and making sure the orientation and airflow are correct for the home’s square footage is a must. Inspect the old furnace before replacing it, to prevent cutting corners resulting in cold spots or unsafe air.