The Ultimate Guide to Buying a Furnace for Your Home

Buying a new furnace can seem like a simple task or it can be an overly complicated one. It depends on who you are and what your level of experience is with furnaces. Like most technical purchases there’s always more than meets the eye. Over simplification can lead to bad decisions, just as easily when feeling overwhelmed. With so many different brands, technologies, features and sizes, not to mention the number of companies advertising their services and special offers, how does a consumer sort through the clutter and make an educated decision?

Most people don’t have the time to learn everything. But before committing hard-earned money to any decision, it’s wise to review some important considerations. We spend a great deal of time educating our customers in person, so we decided to capture some of this advice in The Ultimate Guide to Buying a New Furnace for Your Home.

Being a recognized name in the industry, we hear this question every day. While it's a hard one to answer with accuracy without seeing the job, it’s worth outlining a range of costs and explaining what goes into each job.

If we say the price is $4,000 or maybe $6,500, what does that mean? If the same piece of equipment needs to be installed differently or the job requires some unique attention to ensure comfort, safety and efficiency are achieved, will the price reflect that? With so many installation variables, getting a price estimate can be tricky as it tends to commoditize what you are buying. And there is much more to the equation than just the hardware.

Each market is different, but in our market, a properly installed and commissioned system does take time to complete properly. While the prices vary with the quality associated, generally an upgrade from an older mid-efficient furnace to a high-efficiency furnace can be installed for the following (excluding taxes):

• Entry-level quality, basic single-stage gas furnace with PSC motor - $4,000-$4,500
• Mid-level quality, with two-stage gas burner and standard or variable ECM motor - $4,500- $5,900
• High-end-tier furnace with modulating gas valve and fully variable speed motor - $5.900-$7,500 or more

NOTE: All prices in Canadian dollars and do not include manufacturer or utility rebates

This includes labour, materials and equipment. Options such as filter upgrades, some duct modifications and job site factors add to the end price. Some companies charge more and some less. The same piece of equipment might not be installed in the same manner or with the same care and attention to variables which might affect the long-term operation of the equipment.

Much like purchasing a car, there are several brands, options, sizes and models to choose. But unlike buying a car, the way the equipment is chosen, installed and commissioned is critical and will affect the final price as it relates to time.

Which furnace brand should you buy?

The fact that you might or might not have heard of a particular brand of furnace is really only a function of marketing or your individual experience. It does not relate to the quality of a brand’s product or the experience you will have using or servicing the equipment.

With everyone promoting the benefits of their brand of furnace, how can you tell which one is best? We’ve been in the business for nearly 50 years and we’ve seen and used every brand of furnace on the market. While some brands are better than others, most companies are constantly moving towards better quality and reliability. They have also tried to improve efficiency and overall cost of manufacturing.

We’ve toured factories, spent time in tech

nical training, breaking down and rebuilding furnaces, and of course, we’ve repaired every system installed. The development of high-efficiency furnaces over the past 20 years has created a variety of benefits and problems. In our hyper-connected social media society, it’s sometimes hard to separate fact from fiction. It’s even harder to understand why one brand gets a good or bad review online.

Regardless of brand, every furnace on the market has generally three tiers of product:

• Entry-Level - Often good for mass construction products where low cost and simplicity is needed. We usually don’t recommend this level because the extra cost of a better furnace is often minimal while the comfort and efficiency benefits of the next tier are head and shoulders above this level. But in a budget pinch, or for some applications, the product works. In some cases, it will last just as long. In many cases, however, the warranty, features and flexibility of the product are limited.
• Mid-Tier - Generally very good quality for the mass market with the most important features for comfort, safety and efficiency. This is often where the best value is found, usually at the top of this tier where pricing is balanced with features.
• High-Tier - Usually this is where the newest technology is introduced. Products are normally well designed but can be more complex, requiring better technical training for installation and repair. Pricing is higher due to the cost of features, lower production efficiencies and some pricing strategy in the mix.

The general tendency of technology is to move towards a common design due to cost, engineering limitations or market demand. Yes, there are brands that seem to be taking a low- price, low-quality strategy, but most are constantly trying to improve their cost/quality value relationship. The real issue is that hidden aspects of dealing with one brand or another can be difficult and frustrating, leading to higher costs and lower satisfaction for both the servicing contractor and the homeowner.

Some of the hidden aspects of choosing a specific brand of furnace:

• How easy are they do to business with?
• What is the stock and availability of repair parts?
• How long has the local supplier been supporting the brand?
• Does the brand have a commitment to supporting the customer, dealer or distributor?
• Does the brand understand the environmental or climate differences of the local area?
• Do they make training investments into the dealership network?
• What are the warranty claim procedures?
• What are the after-warranty parts prices?
• Do you have upgrade options in the future?
• Does the brand have a satisfaction guarantee?

The answers to these questions are critical in understanding and predicting future satisfaction. Ask the questions of your HVAC professional and see if they know the answers and can offer factual evidence.

Is the newest technology worth it?

Some brands promote their technology as the best in the business. Some consumers are afraid and view new technology as complex and full of risk. What should you believe? New technology can have risks of failure but in most cases today, the feedback cycle is much faster and correcting issues happens faster. That is not always the case. Some brands have gained a bad reputation as they struggled to identify and solve issues. Working with an experienced HVAC company can help navigate some of these questions and the various internet sources.

Like most technology, there are early adopters and eventually the mass market. As a market moves to mass adoption, the leaders in the industry tend to settle on a similar, or in some cases, the exact same technology. This has indeed happened in the furnace industry. Although there are differences between some aspects such as quality of metal in the heat exchangers, cabinet metal, and components, generally the design has become similar. Sometimes, even the components are from the exact same supplier.

Recently, at least three of the top brands of furnace in our local market were affected by a small electronic component causing all of them to replace their control boards because they were all supplied by the same company. That might make you afraid of the new technology but in fact, the way the company identified the problem and worked to solve it within a short timeframe is a testament to how things have changed.

Newer developments in the heating industry include modulating gas valves, electronic commutating motors and communicating control systems. These items might seem daunting at first but they can make the difference between adequate heat and real comfort. Working with a knowledgeable HVAC company should offer and help you understand the differences.

With dozens of brands each throwing out technical jargon, how can you decide which features to choose?

Generally, aside from furnace size, the two major functional areas of a furnace often boil down to the combustion system and the air-handling system.

The combustion system consists of the gas valve, ignition system, burners and heat exchanger. While most furnaces are generally similar today, the choice of a single-stage, two-stage or multi-modulating gas system is important.

A single-stage furnace operates at one level: on or off. It’s all or nothing, similar to older furnaces. This full-speed operation can be noisier than some furnaces that first operate on lower stages. They can also result in larger temperature swings as the high-stage overshoots the temperature setpoint. Single-stage furnaces are usually less expensive as they are often paired with the cheaper permanent-split capacitor (PSC) motor in the air-handling system. (More about motors in a moment.)

A two-stage gas system provides two levels of heating. In our climate, the lower stage is where most heating is done, unless it’s particularly cold or the system has been turned off and needs to raise more than normal the temperature inside. Some furnaces can manage their two-stage operation from their on-board control in an adequate manner. Sometimes, a two-stage thermostat is recommended to provide more control over the operation.

Common Concern: If you are used to an older single-stage furnace, the new two-stage furnace might seem like it doesn’t heat as well, but in fact, it simply is not heating as hot. The heat coming out of the registers might not be as hot but the result is much more even temperatures with often less air-flow noise. This is achieved by pairing the unit with a multi-speed or variable-speed motor to provide different levels of heat rise in each stage of operation.

A modulating or multistage furnace can provide a great deal of flexibility. The fire size is controlled by the gas valve in concert with the electronic control board by adjusting the size of the fire up or down in small increments. The actual operation of the furnace is affected by the existing temperature and can be influenced by outdoor temperatures, your habits and your specific temperature desires. Some models operate differently than others and some situations don’t require a modulating furnace.

Some systems use proprietary communicating controls. Much like modern computers, the equipment might need to communicate variables between the thermostat, furnace, outdoor condenser or other components to monitor and adjust operation. These controls can be incredibly useful when setting up, maintaining and diagnosing issues. They can also be quite frustrating when the technology is poorly designed, supported or abandoned by the manufacturer.

Whether you need or want more technology really depends on your needs and the current reliability of the technology. One thing is clear: Technology continues to improve, yet that also means furnaces are getting more complex.

Motors

Motor technology has changed. While we won’t go into too much technical detail here, understand that improvements to efficiency and operation have provided more choice.

The old furnaces used what is called a PSC, or permanent split capacitor motor. The PSC motor simply runs at one speed and if there are any air restrictions in the duct system, it can’t compensate for that loss in air pressure. They are cheaper to supply but more expensive to operate. In fact, energy regulators are moving to completely eliminate PSC motors from future residential gas furnaces.

The Electronically Commutated Motor (ECM)

The ECM has been around for a few years and recently has become the standard of Energy Star-rated equipment. With generally two types of ECMs – standard and variable – sometimes it can be confusing for the consumer. Standard ECMs can also be called X-13 motors.

Generally, a standard ECM only has a fixed number of speeds, such as five. Each speed is assigned to a furnace operation, such as stage 1 heating, stage 2 heating, cooling, or circulation. A truly variable-speed ECM is the one that can respond to differences in resistance to meet the airflow requirements.

A variable ECM maintains air cubic feet per minute (CPM) in response to changes in resistance or torque. Similar to cruise control increasing motor power when a vehicle drives up a hill, an ECM will ramp up or down the motor RPM to meet the CFM targets. So, with changes resulting from conditions such as air filters or air conditioning condensation on the indoor coil, the variable ECM can do a better job of supplying more consistent air flow.

The ECM doesn’t have windings but rather uses DC voltage driven by magnetic fields. The motor usually rocks back and forth as it aligns the fields and begins to operate. The ECM has a circuit board in it that is often programmed at the factory, however, there are some motors that are programmed via furnace circuitry or using programming software at local distribution suppliers. This can be an issue when replacement is necessary as the type of programming required will affect how quickly the repair can be done.

Currently, ECMs are more expensive than PSC motors and are often the largest cost difference between different levels of furnaces. Furnaces with variable-speed ECMs are also more expensive than those with standard ECMs. Understanding the difference is one step in understanding what you need and what you are paying for with a new furnace.

Other parts and features can also affect the cost, reliability, comfort and life of a furnace. These include:

• Quality and thickness of the cabinet
• Composition and design of the heat exchanger
• Gas valve, modulating or multi-stage
• Electronic controls onboard the furnace or externally driven
• Inducer or ventor motor - the system used to push out cooler, heavier exhaust
• Communication required or possible with external devices

What size furnace should I purchase?

Sizing a furnace can be tricky and confusing to the average homeowner. While the industry talks technical about BTUs (British thermal units) and heat-loss calculations, the variables in each home are significant. These variables have an influence on what size is required to heat your home comfortably and efficiently.

To properly size a furnace, you need to consider three general items:

1. Understand past or future renovations
2. Assess the existing ductwork
3. Complete a heat-loss calculation of the home

1. Renovation upgrades - past and present
   1. Understanding what has recently been or planned to be upgraded in a home helps to understand the potential impact on energy demands. Increased insulation, ventilation, and new windows or doors could easily reduce the heating needs. Cutting down trees might reduce shade causing heat gain in the summer or winter. Upgrading a roof could change the comfort in a home on a sunny day. Here’s a list of some typical influences on sizing the furnace:
      • Size and style of home
      • Current insulation
      • Number and type of windows, doors and skylights
      • Roofing style and materials
      • Physical location
      • Sun exposure
      • Air leakage or ventilating appliances
      • Other in-home heat-generating appliances or sources
   
   
   2. Ductwork
      1. • With the heating requirements of an average home affected by so many variables, another side of the equation is air delivery. With a forced-air furnace, the smooth and efficient delivery of air is required to properly heat a home, yet a majority of retrofit situations do not allow access to economically address any deficiencies in the existing ductwork. New high-efficiency furnaces require a higher volume of air, and older or poorly designed duct systems might not allow for the required air to carry the heat for that home in every circumstance. Something called external static pressure is an extremely important consideration. If the available airflow is restricted or reduced, the air can’t be delivered to the areas needed. Also, in some situations, the calculated heat loss of the building might require a furnace size that the duct system can’t handle. As a result, you might need to decide between investing in ductwork improvements or choosing a less-than-ideal heating solution that can work with your existing system. Some modifications are not as expensive as you might think and can have a major impact on the comfort and efficiency if you are willing to consider them. Ask your HVAC professional what they would recommend and why. Reputable companies will usually point out the options they recommend proactively to ensure you understand where improvements are possible.

      Pro Tip! Working with a company that has formal training on airflow is highly recommended. Some jurisdictions allow anyone with a gas-ticket to install a furnace, yet they might or might not have any training in the delivery of airflow. In our local area, we have a professional organization known as the Thermal Environmental Comfort Association (TECA). In other jurisdictions, they will have something similar dedicated to quality and education of the industry. Working with a company that understands the importance of air delivery is an important key to a quality job and can affect the recommended size and the final price.

   3. Heat loss/gain or heat-load calculations
      • In a perfect world, a heat-load calculation would be performed to estimate the actual heating needs of the home. While this is ideal, the practical limitations of a competitive industry such as the heating business create challenges. There are some different types of heat-load calculations, and some take a great deal of time and effort to complete. Normally the homeowner doesn’t want to pay for this, as everyone provides “free” estimates. Some companies offer to complete the calculations for a fee, while others are willing to complete one upon agreement to proceed with an installation contract. Others still have years of experience and use their knowledge as a rough-thumbnail guide. If they are asking the right questions and doing a detailed inspection, the representatives can often recommend the correct product. This quote process is due in part because the industry sells furnaces in increments of 20,000 BTUs. So, they might formally calculate a 70,000-BTU heat load, but they must choose between a smaller or larger furnace either way. This can partially be handled by effective installation, commissioning and some possible airflow improvements. But there are issues with an oversized or undersized furnace. Overall, if you are concerned about a scientifically accurate sizing of the furnace before you sign a contract, hire someone to do the full heat-load calculation that isn’t selling you a furnace. The company selling the furnace should be able to complete the calculations, but you need to be comfortable with the advice you are getting.

Under-sizing a furnace can lead to poor performance and an inability to heat the space required, but oversizing can be just as problematic, if not worse. For example, if a building requires 70,000 BTU of heating, installing an 80,000-BTU furnace, especially in a duct system that can’t handle the air required, will lead to short cycling of the furnace and constant temperature swings. Every time that furnace heats up and contracts, that’s a cycle within a limited lifecycle. This will shorten the life of the furnace and reduce the comfort of the occupants during operation. It will also never achieve the efficiency promised or rated by the manufacturer. In this case, a 60,000-BTU furnace would be the next step down. While it might struggle to keep up on the coldest of winter days, generally it will run longer and most likely will reach temperature.

Filters are the often-misunderstood area where homeowners either spend little concern or too much money. There is an entire industry built around effective and efficient filtration, with a lot of science and even more mystery behind it. For the purposes of this discussion, focusing on some basics will help.

Filtration vs. Airflow

Filters are the single most important area where a homeowner can make or break their furnace. Leaving a filter in too long can cause premature parts failures due to overheating and/or overworking. The simple reason is that when you restrict air from flowing across the heat exchanger, you allow heat to build up higher and longer than you want. Plus, the additional strain on the blower motor is a recipe for disaster.

Sometimes homeowners will replace their filters with what they believe to be extremely high-quality filters only to learn later they have restricted the airflow so much that the damage has been done.

The benefit of the four-inch filter is twofold. First, you get more effective filtration, but more importantly you get more efficient airflow which is good for the furnace and better for the air distribution. Better airflow improves the comfort and efficiency and improves the life of the furnace by taking the heat out of the furnace. The four-inch filters also do not need to be changed more than once or twice per year. Overall, they’re as cost-effective as a one-inch filter.

Other more expensive and complicated filtration or cleaning systems do exist. Some are based on science and provide a solution for some serious health concerns. Others are based on hyperbole and feed on fear or trends. The fundamental concern is the trade-off between cleaning the air and restricting the air. Don’t be impressed by the brochure if it doesn’t provide the facts.

Aside from potential quality and design issues, every furnace is highly affected by the quality of installation. An industry study suggests that 80 per cent or more of furnace issues are actually a result of installer error. This is a critical fact as it enforces the importance of choosing an experienced and quality installation company. Too many times we have seen exceptionally good equipment fail because the company that installed it allowed for poor installation habits.

Things to consider with installation:

• What is the heat loss or heat gain in the spacing being conditioned?
• How will the filter be accessed?
• What service access is required in the future?
• Can parts be removed if they need to be replaced?
• Does the furnace require a specific slope or level?
• Is new venting required and if so, where and how will it be run?
• How will the exhaust termination exit the building and how will it look?
• What are the venting limitations? How long and what size is needed?
• How long or how wide is the venting material needed?
• What gas pressures are required?
• What specific requirements are needed by the manufacturer?
• Where is the condensation going to drain?
• What material will be used with the condensation drain?
• Is a condensate neutralizer required?
• What are the municipal or local requirements?
• Is there enough airflow?
• What are the air settings required?
• Does the system need circulation air?
• Will the thermostat wire need upgrading?
• Will air conditioning be required or desired in the future?
• Is humidification or dehumidification required?
• Is sound an issue?
• What improvements can or should be made to the supply or return ducting?

A typical quality installation process will consist of the following:

1. Assessment of existing ducting and area to be heated/cooled
2. An offer of improvements of deficiencies
3. Clean and careful removal of old equipment
4. Sealing ductwork joints in furnace vicinity
5. Sealed, accessible filter cabinet with a good-quality filter
6. Proper furnace placement and levelling as recommended by the manufacturer
7. Proper drainage tightly connected to a drain or pump
8. Two-pipe combustion venting, where possible
9. Programmable thermostat and wiring upgrades to fully operate the new furnace
10. Proper commissioning and documentation of the system, including gas pressures, air speeds, temperature rise and static pressures
11. Homeowner education and maintenance recommendations
12. Warranty registration and satisfaction followup

The complexity of installing these systems can seem overwhelming, leading to over-simplification by installers. Yes, they can make it work but if they don’t take the time to install it properly and commission it fully, the equipment won’t provide the comfort or long-term efficiency possible. For a more detailed review of quality installation guidelines, see this article

Obviously, price is only one aspect of any purchase. Understanding what you are receiving for that price can be difficult with over-simplified and slick marketing tactics.

Do your homework to understand the differences between brands, models and their technology, but also take time to understand how the equipment needs to be installed and what goes into a quality job. Working with a good HVAC company will help you cut through the clutter and make the decision easier.

Good companies do exist and can be found by considering:

1. Online reputation and feedback (Google reviews, BBB ratings, Homestars, etc.)
2. Certifications, licences, training (ask for their credentials)
3. Insurance and Workers Compensation (Don’t take shortcuts)
4. Membership in professional and consumer organizations (Do they care?)

Good companies are more interested in educating their customers and doing thoughtful analysis more than pressured sales pitches. Companies focused on continuous training and upgrading of their technicians ensure they are up to date on standards, equipment, safety and efficiency factors. This does cost money and can affect the price of what you buy, but in the end might save you money by working with a company focused on quality.

As the “common law of business” states:
“There is hardly anything in the world that someone cannot make a little worse and sell a little cheaper, and the people who consider price alone are that person’s lawful prey. It’s unwise to pay too much, but it’s worse to pay too little. When you pay too much, you lose a little money — that is all. When you pay too little, you sometimes lose everything, because the thing you bought was incapable of doing the thing it was bought to do.

The common law of business balance prohibits paying a little and getting a lot — it can’t be done. If you deal with the lowest bidder, it is well to add something for the risk you run, and if you do that you will have enough to pay for something better.”

-John Ruskin, 19th Century