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If your HVAC technician wants to size a new furnace for your home by its square footage alone, or using some other discredited “rule of thumb” method, you should change technicians. Furnace sizing involves an engineering methodology developed by the Air Conditioning Contractors of America (ACCA), which has been time-tested and energy-budget approved. Here’s why and how.

Heat Gain, Heat Loss

A home’s heat gain/loss totals the heating load placed on the furnace. A new furnace should be sized to meet the load, or it will be over- or undersized. For instance, take two very similar homes, in terms of floor plan and square footage, located in the same neighborhood; the old rule-of-thumb furnace sizing method would result in the same size furnace installed in each home.

However, what about the heat gain/loss properties? Perhaps each home has a different orientation to the sun. One home has Energy Star-qualified windows, and has undergone air sealing and insulation upgrades. The other home has not. It is likely each home will require a different size furnace. Here’s why:

Furnace Sizing

These are the basic steps you and your HVAC contractor should take when sizing your new furnace:

For complete details about proper furnace sizing for your Portland area home, please contact us at Roth Home & Cooling.

Taking a whole-house systems approach to energy efficiency will lower your energy bills. This is an important undertaking when you want reduced costs without sacrificing comfort. Energy losses occur through your home’s envelope because of heat transfer. Heat constantly seeks out cold, so by sealing the air leaks, adding insulation, improving weatherstripping and making lifestyle changes, you can keep your home more comfortable without relying so heavily on your HVAC system.

Air Leaks

Over time, buildings settle and caulk shrinks, so it’s a good idea to go through your home, looking for gaps around window frames, the foundation and inside the attic where air losses can occur. Any place where infrastructure enters or leaves your home can have a gap around it as well, especially in the attic or foundation of your home.

These holes and gaps are easy to fill with caulk or expanding foam. Exterior doors may need fresh weatherstripping, another easy task to improve energy efficiency.

Insulation

The amount of insulation in your home’s attic should range between 16 and 20 inches for the best thermal protection. Options include fiberglass batts or blown-in loose insulation. They’re relatively easy to install, and once in place, start to work immediately to cut your energy costs. Adding more wall insulation is more challenging and may require a contractor who specializes in blown-in insulation or spray foam. To get the most from the whole-house systems approach to energy efficiency, it’s best to start with the attic.

Lifestyle Changes

To learn more about the whole-house systems approach to energy efficiency, contact our pros at Roth Home & Cooling, providing top-notch HVAC services for the Portland area since 1976.

Do you have problems with your heat pump freezing up in cold weather? While the presence of a light layer of ice on the unit during our cold Portland winter weather is fairly normal, heat pumps do sometimes freeze up. Typically, the periodic defrost cycle keeps the unit sufficiently ice-free to maintain proper functioning. Nevertheless, when the unit freezes for an extended period of time, the freezing issue should be addressed. Be sure to turn your thermostat to the emergency heat position and use an alternative heat source to avoid running the unit while it’s frozen. It won’t do you any good anyway, until it’s fixed.

Heat pump freezing may be caused by technical issues such as a defective defrost control or timer; however, the following are four common causes of freezing:

It’s critical that these items be addressed as soon as possible to avoid serious damage to the unit. Once you start troubleshooting, you may find that blocked airflow or a blocked fan problem caused by ice buildup or roof drainage are problems that you as the homeowner can solve. When a frozen heat pump is caused by a refrigerant problem or a defective control or fan motor, however, it’s time to contact a professional heating, ventilation and air conditioning company.

Unfortunately, the heat pump freezes when you need it the most – during those cold weather months here in Portland. If your unit is freezing up and you have been unsuccessful at solving the problem, contact Roth Heating and Cooling. With more than 35 years serving satisfied customers in the Portland area, Roth Home is available to perform regular heat pump maintenance, or the occasional emergency service call, if needed.

Consider all the pollution generated in your home every day. Cleaning, cooking, burning fuel, bathing and even breathing create moisture and pollution you want to expel from your house. The kitchen, bathroom and laundry room are the biggest culprits for generating pollution, from fumes and smoke to grease and dust. The best way to get rid of these pollutants is by installing exhaust fans. Here’s a look at the types of exhaust fans available and the benefits they provide.

Types of Exhaust Fans

Benefits

Exhaust fans vent pollutants to the outdoors, but what exactly are the benefits of proper home ventilation?

For more about choosing the right exhaust fans, please contact Roth Home & Cooling in Portland today.

As a Portland-area homeowner, you probably already know that energy efficiency is not simply a noble gesture toward conserving natural resources; it can lower your fuel bills, too. A condensing gas furnace is one of the most efficient ways to keep your home and family warm.

Efficiency by the Numbers

Furnace efficiency is measured using Annual Fuel Utilization Efficiency(AFUE), a metric that allows quick comparison. Standard furnaces 15 to 20 years old probably achieved around 65 percent AFUE. While modern conventional furnaces can achieve around 80 percent AFUE, condensing gas furnaces can climb to a whopping 98 percent efficiency.

Follow the Heat

To achieve such astounding fuel efficiency, a condensing gas furnace recaptures heat from combustion by adding a second heat exchanger to the process. The cold air return draws air into ducts, through a high efficiency air filter, a blower (this could be variable speed for even greater efficiency) and over the first heat exchanger.

The air gains thermal energy and passes a second heat exchanger, and here’s the heart of the difference between a regular furnace and a condensing gas furnace. Combustion exhaust gases heat the second heat exchanger, wringing every bit of thermal energy out of the hot gas as it condenses into a mixture of water, carbonic acid (formed from carbon dioxide resulting from combustion) and other exhaust. The condensate drips out of the exchanger, and remaining gases – at only around 100 degrees – exhaust outdoors through plastic pipe. The heated air passes along ductwork and out into your home.

Condensate drains into a floor drain through a tube, which must be kept clear and free of bends or kinks. If condensate stays in the furnace, it will eat holes through metal, ruining your condensing gas furnace.

Other differences between conventional and high-efficiency condensing gas furnaces:

To learn more about the great energy savings you can achieve for your Portland area home with a condensing gas furnace, please contact us at Roth Home & Cooling.

If you need to replace the furnace in your Portland area home before the worst of winter arrives, you may want to consider one of the newer types of energy-efficient models, such as a two-stage furnace. Compared to the traditional single-stage version, a modern two-stage furnace has several advantages.

Increased Comfort

A single-stage furnace has only a single high setting, so it cycles on and off to keep your home at the desired temperature. Between cycles, you may notice certain areas of the home are cooler than others, decreasing the perceived comfort level. With a two-stage furnace, it operates up to 80 percent of the time on a low-heat setting, constantly distributing warm air and preventing the development of cold spots. On colder-than-average days, it uses the high-heat setting to maintain temperature.

Efficiency

Because the two stage-furnace operates on the low setting most of the time, only switching to high on the coldest days, it uses less energy than a single-stage furnace that’s designed to run at full capacity no matter the temperature. The consistent warm air and reduction of cold spots keeps the home comfortable even in colder climates, reducing your temptation to turn up the thermostat and adding to your savings. Finally, by using a variable-speed blower motor instead of the older single-speed models, electricity consumption is greatly reduced.

Quieter Operation

The variable-speed fan of a two-stage furnace operates at low speeds most of the time, which decreases the amount of noise you hear during the furnace’s operation. In addition, speed changes occur gradually, eliminating the sudden noise increase that happens when a single-stage furnace turns on.

Better Filtration

The slower speed of the fan allows air to move through the air filter at a slower rate. This allows the air filter to more efficiently remove contaminants, increasing indoor air quality and helping those with allergies or asthma.

If you have considered the advantages and would like to upgrade to a two-stage furnace for your home, please contact our expert technicians at Roth Home for an estimate today. We have been serving the Portland area since 1976.

You want the cleanest air possible for your Portland area home, but improving your indoor air quality isn’t as simple as installing the most efficient air filter you can find. The choice of low- vs. high-efficiency air filters depends on your home situation and your heating and cooling system design.

The MERV Scale

The MERV (Minimum Efficiency Reporting Value) scale helps you decide about low- vs. high-efficiency air filters. This system ranks filters based on how efficiently they trap air contaminant particles of certain sizes. The higher the MERV number, the more efficient the filter.

Why Higher Efficiency Isn’t Always Better

The more efficient a filter, the greater the density of its media. A dense filter slows down air moving through it, forcing the fan motor to work harder to maintain optimal airflow. Filters above MERV 13 are too dense for many residential systems. These are likely to strain the motor and cause early failure, unless modifications are made to the equipment.

Choosing low- vs. high-efficiency air filters requires finding a balance between efficient filtration and sufficient airflow. The good news is that filters of MERV 7 to 13 are almost as efficient as HEPA filters, according to U.S. Environmental Protection Agency research. If you want a filter with a MERV higher than this, consult a heating and cooling professional first.

A true HEPA filter may benefit you if you have respiratory health concerns. To add whole-house HEPA filtration, however, you may need a bypass system. This add-on system redirects air for filtration without impeding airflow. HEPA filters also come in stand-alone air cleaning systems.

At Roth Home & Cooling, we can help you navigate the world of air filters and cleaners, and improve the air quality in your Portland area home.

Our goal is to help educate our customers in the Metro Portland area about energy and home comfort issues (specific to HVAC systems).

Is it time to replace your old furnace, and you’re considering installing a high-efficiency furnace for better comfort, lower heating bills and a nice return on investment. If so, use this guide to better understand why a high-performance system is only as efficient as the indoor environment in which it’s installed.

Forced-Air Systems

Your new high-efficiency furnace is but one component of the forced-air system within the home. The forced-air system consists of the ductwork, thermostat controls and duct add-on components that affect comfort, efficiency and/or indoor-air quality, such as whole-house dehumidifiers, zoning and UV-light systems.

All of these correlative components must work together efficiently to maintain balanced air pressure and free airflow through the living spaces and ductwork, in order to maximize furnace performance.

Sealing Your Home’s Envelope

The performance of your high-efficiency furnace largely depends on the heating load placed on it. In fact, a new furnace should be sized by taking into account various factors that contribute to the heating load, such as airtightness and insulation levels.

The best way to reduce the heating load placed on the furnace is to conduct an energy audit to identify air leaks and insulation deficiencies in the home’s envelope. Following the energy audit, your HVAC professional will seal up cracks and gaps around doors and windows, the attic, basement and exterior walls.

Once your home is sealed up, insulation upgrades are performed, if needed, to boost levels to recommended R-values. Your buttoned-up home will keep heat inside longer, which reduces the amount of time and fuel required of your furnace to heat it.

Furnace Installation Checklist

To make easy work of your furnace upgrade, and to create an indoor environment that promotes peak performance from your high-efficiency furnace, use this simple checklist:

For help in the greater Portland area with high-efficiency furnace installation, preventive maintenance and home-efficiency evaluations, please contact us at Roth Home & Cooling today.

Don’t be left out in the cold this winter if you use a boiler to heat your home. Pay attention to whether or not your unit is plagued by the following problems, which could signal bigger problems to come.

Is there any rust present? Rust on or inside your boiler is a sure sign that trouble’s on the way. You should have your unit inspected regularly for rust and other signs of corrosion. Schedule a yearly inspection for your boiler system that includes a visual check of its inside.

Are there any leaks? Simply walking around the system to inspect for leaks is a good place to start. However, sometimes the leaks can be hidden or buried in pipes that are not visible. Any pipes that are underground should be assumed to be leaking, as these can fail more quickly than pipes that are not underground. Check for rust-colored stains near the discharge piping, and look to see if the pop safety valve has been replaced. Both are signs of an underlying issue with your boiler.

Is it making strange noises? Your boiler system making strange noises, or “kettling,” can signal lime buildup or rust clogging up your system. Your system also may make noise if air is trapped in it, or if the pump is going bad. Sometimes these issues can be repaired in order to extend the life of your unit. Contact a professional to service the boiler and see what might be causing the noise. He or she can determine if repair or replacement is the most cost-effective option.

Is it heating? If your unit is not heating the house as well as it used to, or not heating the house at all, contact an HVAC professional to diagnose the issue.

For more information on keeping your family warm and cozy this winter, contact our professionals at Roth Home & Cooling. We have been serving the Portland area since 1976.

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