Cold Weather Home Design and Remodeling - What Is A Heat Recovery Ventilator?

Heat Recovery Ventilators - Madison Wisconsin Remodeling

What is a Heat Recovery Ventilator? Fresh air in a Wisconsin Winter!

Back in the 1970's–before the energy crisis–when you were chilly, you merely cranked up the heat. Today, with unstable energy prices and an increased awareness of the environment, we're all seeking ways to save money and energy when heating our homes during the cold months.

Of course, taking simple action like sealing up drafts around windows and doors and increasing insulation in the attic can help, but there's also an HVAC technology available that is a perfect way to improve the efficiency of your homes heating system. If your remodeling your home, adding a heat recovery ventilator to your homes HVAC system can increase the efficiency of your heating, lower your energy use and cost and re-circulate clean, warmed air, while removing stale air from your home.

Let's take a look at what a heat recovery ventilator does, how it works, and why it's a smart addition to any home that is in a cold climate like Wisconsin.

What Does A Heat Recovery Ventilator (HRV) Do?

Aprilaire 8100 erv. photo courtesy of aprilaire corp

Aprilaire 8100 erv. photo courtesy of aprilaire corp

A heat recovery ventilator is designed to remove stale, polluted and humid air from inside your home while introducing fresh, dry warm air. The mechanism of an HRV is designed to transfer the heat from the stale damp air by using the exhaust air to preheat the fresh incoming air. This saves you on energy costs while reducing condensation, mold, and mildew.

New home builders and home remodelers have worked over the past decades to increase home efficiency. By replacing old windows in older homes, installing tighter doors, adding modern siding and caulking every crack, older homes were brought up to a modern standard of efficiency. New homes today are being built from the ground up in thermally efficient ways.

View Our New Home Construction Portfolio

It turns out that those natural inefficiencies in older homes worked to provide fresh air into the home during the cold months when the windows were kept closed. Without being aware of it, builders before the energy crisis were unintentionally installing an adequate ventilation system, if you could afford the heating bills!

Today, HRV technology can provide clean preheated air, while removing pollutants like VOCs, radon, CO2, and moisture, actually improving the energy efficiency of your home.

How A Heat Recovery Ventilator Works

An HRV uses a simple process for transferring heat.

aprilaire erv exchanger core. photo courtesy of aprilaire corp.

aprilaire erv exchanger core. photo courtesy of aprilaire corp.

  1. Stale, humid air is exhausted from your home. As the air passes through the HRV, it warms the plates of the heat exchanger core.

  2. Clean outdoor air is brought into the house from outdoors. It is passed over the warmed heat exchanger plate, then deliver through venting into your home.

  3. Both processes occur simultaneously. While the supply and exhaust ait streams never mix, heat energy is continuously exchanged between the two.

Heat recovery ventilation units have two fans and a built-in “air-to-air heat exchanger which transfers heat from the exhaust airstream to the cold, fresh, incoming air supply. Using the natural laws of physics, whenever cold air is warmed, humidity is removed and condensation control is the result. The two air streams are kept completely separated at all times. The fresh air brought into your home is warm, dry, and healthy.

If You Live In A Cold Climate, An HRV System is A Smart Upgrade

An HRV offers a level of energy efficiency unmatched by any other appliance. It can recover up to five times more energy than it uses to operate. Unlike other condensation control devices, like dehumidifiers, HRVs perform best when conditions are at their worst. Sunshine, a warm attic or heating elements are not required, HRVs ventilate and recover heat around the clock, every day.

While an HRV is not a heater or a heat pump, it can lower your energy costs by recycling the heat from your home as it recirculates fresh air from the outdoors into your home. This includes all of the heat your home generates, not only from your HVAC system but from log fires, electric heaters, appliances, your stove, whatever the heat source and HRV will recover the heat from the exhaust heat stream and recycle it right back into your home.

This is energy recycling in a very efficient manner. Effectively, you are using the same heat over and over again. On a typical winter day in a cold climate, the energy recycled can be as much as 500% of the cost of operating the two fans in the unit.

If you'd like to learn more about Degnan Design-Build-Remodel's energy efficient approach to design and remodeling here in Wisconsin, send an email or give us a call at (608) 846-5963. We're always happy to answer any questions you might have.

This article was updated by Abe Degnan on 6/25/2018.

About Degnan Design Build Remodel
Since 1981 Degnan Design Build Remodel has provided home improvement and construction services to customers throughout Greater Madison, Wisconsin. Our goal is to WOW you with a "Designed For Your Life" solution using a process that will transform your home into a beautiful living space, delivered on time, and on budget. We are known for our communication, respectfulness, and a commitment to our customers and our community. Contact us to speak with one of our designers about your home improvement project.