Traditionally, in the summer, we close the doors and windows to keep the heat out. When winter arrives, we shut these same entry points to keep the warmth inside.
But, have you ever wondered what happens to indoor air quality when you shut the windows and doors?
It’s a valid question because the air in an airtight home is rarely of good quality. It’s often short of oxygen and filled with odors from the bathroom, allergens from pets, and dust and dirt particles.
How are you supposed to get these elements out of the house without compromising indoor airtightness?
In three words – Heat Recovery Ventilation (HRV)!
Heat recovery ventilation (or a variation of HRV known as Energy Recovery Ventilation (ERV)) brings fresh air into the home without allowing indoor heat to escape.
This guide focuses on the best heat recovery ventilator (HRV), though we’ll also touch on a few aspects of ERV systems and how you can go about choosing the best model for your needs.
6 Best Heat Recovery Ventilator Reviews
1. Fantech Flex 100H heat Recovery Ventilator (HRV) 0.4 W.C.
- Airflow up to 105 cfm @ 0.4" PS serves 1 to 7 bedroom homes
- Top-mounted ports for easier duct connectivity
- Unobstructed front access
- The TurboTouch feature delivers up to 50% more exhaust capacity
- Aluminum core provides superior heat transfer capability
The compact yet powerful Flex 100H from Fantech is an incredibly efficient heat recovery ventilator ideal for high-rise apartment applications, single and multi-family homes, and condominiums.
It features a compact top port design, with five-inch oval collars, and installs in spaces as tiny as 24 inches, such as in closets and maintenance rooms. An EZ-mount wall bracket is included in the package.
The unit implements integrated airflow measurement for rapid and accurate reading and supply of airflow. Indeed, one of the standout features of the HRV is the TurboTouch. This feature allows the Flex 100H to deliver 50% more exhaust capacity whenever additional airflow is needed.
The ventilator supports airflows up to 104 CFM @0.4 inches per second and can serve up to four bedrooms in the home. Other features of the Flex 100H include top-mounted ports for easier duct connectivity, unobstructed front access, and an aluminum core for efficient heat transfer.
- Compact top-port design
- Moves air at 104 CFM
- Wall brackets included
- Internal washable filters
- One of the more expensive products on this list
- No remote control
2. VTRONIC Wall Mounted Ductless HEPA Ventilation Fan
- Easy to Replace No Need Any Tools You Can Replace it Easily
- High Efficiency HEPA Filter H11 Level Bring Fresh Air for Your Families
- Widely Using You can Get it Working with Our Wall Mounted HRV Fan
- Overlay HEPA Design to Extend the Filter Area for More Volume Air
- Advising 3-6 Months to Replace it
The VTRONIC heat recovery ventilator comprises a telescopic adjustable-length duct regulated by an inner duct. Inside the unit are three filters to clean up the fresh inbound air. It’s very silent, producing a maximum of 30dB thanks to the high-performance brushless motor and sealed wall-mounted design.
The unit draws 2 to 6 watts of electric power and operates at between 28 CFM and 35 CFM, making it suitable for the bedroom. It features three ventilation modes – Fresh Air, Exhaust, and Cycle.
In the Fresh Air Mode, it 100% supplies fresh air while in Exhaust Mode, it 100% extracts stale air. In the Cycle Mode, however, it both supplies and extracts in 65-second cycles.
The VTRONIC is equipped with a functional remote control for easy operation and backed by a 12-month warranty.
- Three-mode operation
- Remote controlled
- Silent at just 30dB
- 12-month warranty
- 28-35 CFM isn’t very strong
- No timer
3. Tjernlund X2D Model Products Xchanger Reversible Basement Fan
- Reversible basement air exchanger ventilates damp and musty basements
- Two 90 CFM fans can individually be reversed to exhaust musty air or supply fresh air to basement
- Includes adjustable dehumidistat and pug-in electrical
- Exterior hood has removable screen
- Includes magnetic covers for winter use
- Hood separate from fans for installation flexibility
The X2D from Tjernlund is a reversible basement air exchanger that operates at 90 CFM. It can be set to 100% supply fresh air into the room or 100% remove stale air out of the room. Alternatively, you can achieve both goals at a go – simultaneously bring in fresh air while also eliminating bad air out of the home.
The unit runs on just 40 watts and easily installs in a 5.25 x 12.25-inch cutout through a wall or rim joist. A six-foot power cord and exterior hood are included for trouble-free installation. Other features that stand out about the ventilator are the adjustable humidistat, magnetic covers for winter use, and plug-in design.
This ventilator is recommended for basements but also works well in sealed crawl spaces, storage areas, workshops, and garages.
- Durable, rugged outdoor hood
- Consumes just 40 watts per hour
- 3-way air extraction/supply operation
- Inexpensive (at under $200)
- The included filters are not of very high quality
4. Panasonic FV-10VE1 Intelli-Balance 100 Energy Recovery Ventilator
- Aerodynamic low profile reduces wind drag, saves fuel
- Quiet power: Delivers the optimum balance of air flow
- Easy-to-reach, easy-to-use controls - three-speed blower
- Manual, electronic and wall thermostat controls; Input voltage (AC): 115 V
- Pre-installed module board & heat strip for thin ceiling application
As with most Panasonic products, the 50-CFM FV-10VE1 is a high-quality ventilator manufactured with keen attention to detail. Also popular as the Intelli-Balance 100, the unit effortlessly withstands extreme temperatures, thus keeps going even when temperatures drop to 14°F.
The ventilator implements a smart-flow technology where when the fan senses static pressure, the speeds automatically increase for optimal CFM output. Even better, it features a built-in adjustable fan timer that allows you to set the fan to run for a specified amount of time (0 to 60 minutes). This should make your life much easier.
The unit is easy to install, with ceiling mounting brackets included. It consumes 80 watts per hour and requires a 4-6-inch ducting.
- 50 CFM output is adjustable to 100 CFM
- Washable air filters
- Mounting brackets included
- 3-year parts warranty
- 6-year motor warranty
- Slightly pricey (at about $1,000)
- Filters are expensive (at about $50 each)
5. Tjernlund RT750 Draft Inducer with Fan Prover Switch for Gas Heaters
- Stainless steel backward inclined impeller repels soot and lint
- Clamshell design for easy installation, servicing and inspection
- Patented motor cooling system automatically activates, extending motor life
- PSC ball bearing motor with -40F low temperature lubricant
- High temperature powder coat finish
The most expensive product on this list and the most unique, the RT750 draft inducer from Tjernlund, is part of the company’s RT series of rooftop draft inducers for oil and gas, solid fuel, and general ventilation applications. It’s ideal for either metal or tile-lined flues and comes with removable hinge pins for easy maintenance.
Manual speed adjustment allows you to fine-tune ventilation performance while the self-cleaning backward-inclined fan blades prevent the buildup of soot. Hearth models include a speed control with the chimney while gas and oil models feature a fan-proving switch that can be paired with interlock controls for safe, automatic use.
The RT750 comes in stainless steel construction, with a hi-temp powder coat finish. It’s a relatively large unit at 22.5 x 21 x 22.5 inches and weighs 54 pounds.
- Durable stainless steel build
- Hi-temp powder coated finish
- Self-cleaning fan blades
- (Manually) adjustable speeds
- Pricey (at over $1,000)
- Requires professional installation
Buying Guide for the Best HRV System
Increasing costs have been a significant detractor in home heating and ventilation. Back in the 60s and even 70s, when heating and ventilation costs were very low, you could crank up the thermostat without burning a hole in your pocket. Electricity was cheap, so in the end, you only spent a few more dollars (not hundreds) for the extra heat.
Fast forward to the 90s, and an extra degree on the thermostat could cost you hundreds at the end of the year. A 5-degree temperature increase guaranteed thousands of dollars in additional heating costs.
So, as technology advanced, people found that sealing up the home was the best defense against heat loss and the huge heating bills. As a result, houses began to invest in tight windows and doors, modern sidings, and aggressive caulking. Vapor-barrier improvements and insulation became standard in the contemporary home.
This trend has remained to date. But, the tight sealing presents a new problem – ventilation. A tightly sealed home excellently retains heat, saving owners and renters thousands in yearly bills. But, it also leads to a stuffy, not-so-livable environment. That’s where the need for heat recovery ventilation originated.
What’s a Heat Recovery Ventilator?
A heat recovery ventilator is similar to a balanced ventilation system. It comprises of two ventilation ducts running next to one another and passing between the indoors and outdoors. The first duct system carries cool, fresh air into the house while the second one carries moist, stale air out.
That sounds straightforward, right?
Well, it’s not so simple. The clever bit of the entire arrangement is that the airstreams run through a device known as a heat exchanger that allows the outgoing air to pass over most of its heat component to the incoming air. All this happens without the two streams of air mixing.
The result? Stale air is carried outside the house without losing the indoor heat. At the same time, you receive fresh air from the outdoors into your home!
How HRV Systems Work in a Single Room
When the HRV system is installed in a single room, it’s called decentralized heat recovery. You can choose to install the unit from a single point or multiple points depending on the size of the room and how you intend to use it.
Anyway, once the installation is complete, the system works in short cycles that (in most cases) automatically switch over during operation.
- 1st Cycle: Stale air and moisture from inside the house are pumped outside via the first duct line. As the air passes through the heat exchanger, the heat within it is retained and temporarily stored.
- 2nd Cycle: Fresh air is drawn into the house through the second duct line. The heat retained from the first cycle is released into this stream of fresh air as it passes through the heat exchanger.
The short-cycle operation allows the HRV system to facilitate heat exchange without mixing the two streams of air.
You can also read about the best exhaust fans for garage.
Are Heat Recovery Ventilators Effective?
It’s not yet possible to retain all the heat from the air leaving the room. However, heat recovery ventilation technology continues to get better. Today’s HRVs retain about two thirds to three-quarters of the heat from the stale air headed outside the house, though e few very efficient models can retain as much as 95% of the heat.
With regard to potential energy savings, the figures vary from one location to another. According to some experts, the HRV system can cut energy losses in a “leaky” house by half. This usually translates to as much as 65% in energy savings.
What you must remember, though, is that the HRV system also relies on electricity to work. The majority draw between 50 and 100 watts per hour when operating, whereas a few need as much as 300 watts. This cost is usually subtracted from the projected energy savings.
Heat Recovery Ventilation System Pros and Cons
The energy savings we’ve just discussed isn’t the only advantage of heat recovery ventilators. Other advantages of these systems include;
- Maintain airtightness without compromising indoor air quality: Maintaining an airtight home, especially during the cold season, can be the difference between a warm home with fairly manageable energy bills and ineffective heating with sky-high electricity bills. HRV systems allow you to maintain the airtightness without compromising indoor air quality.
- Maintain the right moisture levels in the home: This is another vital benefit of HRVs. They keep your indoor humidity levels balanced without compromising heating or cooling. If it’s too moist indoors, the HRV system will pull out the excess moisture. If it’s too dry indoors, they draw more moisture into the house as the fresh air from the outdoors enters the home.
- Cleaner, healthier indoor air: You’ll realize that as the stale air leaves your home, it usually leaves with the dirt, dust, and microorganisms such as allergens that might have been in the room. This can help prevent allergies and many other health issues associated with poor quality indoor air.
- Savings from reduced maintenance costs: A good balance of moisture inside the home will ultimately also result in reduced condensation, fogging, and general humidity. Mold and bacteria, for instance, will be gone. It could also be what helps you preserve your walls (painting and wallpapers) and prevent rotting. The result is reduced maintenance needs and, ultimately, cost savings.
Despite their many advantages, heat recovery ventilators have a few downsides. The two main challenges are;
- High initial costs: The initial costs of installing a heat recovery ventilator are slightly high. Even a standard HRV costs several hundred dollars, with the most efficient models costing a few thousand.
- You may not recover your investment: What makes the high initial cost situation worse is that you’re unlikely to quickly recover the costs. These appliances rarely save more than $100 per year on energy. It means that it could be more than ten years before you’re close to recovering your investment. Since many of the devices have a 10 (or so)-year life, it’s possible not to recover the investment at all.
However, if you’re keen on heat recovery ventilators, the above two issues shouldn’t put you off because HRV significantly improves the quality of indoor air. It’s the ultimate solution to indoor odors, excess moisture, and allergens. You put a price on that as it saves you from coughs, sneezes, allergies, and many other health issues.
ERV vs HRV
Energy Recovery Ventilators (ERVs) are a variation of heat recovery ventilators (HRVs). The two systems use the same working principle. The only difference is that in ERVs, the system allows for partial transfer of heat – and moisture – from the outgoing stale air to the incoming fresh air.
What’s the benefit of the humidity transfer?
There are a couple. First, if you live in a humid climate, the process will help block out excess humidity. By circulating the indoor moisture, you prevent loss of in-home moisture while keeping out excess moisture from the outdoors.
Secondly, it reduces the load on your air conditioner, thus lowers your air conditioning bills. Since it helps maintain the right indoor humidity level, your AC doesn’t need to work very hard, meaning lower bills and a longer AC life.
Finally, the ERV can serve as your air conditioning system. In homes or rooms without an air conditioner, the ERV will step in and diligently perform the AC role. This works particularly well in climates where not much air conditioning is needed.
Are Heat Recovery Ventilator Systems Worth It?
The short answer is – yes!
In a location with freezing winters and overly hot summers, the HRV (or even ERV) can be the difference been a comfortable home and an unlivable one. These two appliances help to keep indoor temperatures in check and also help maintain balanced indoor humidity. Better still, they keep indoor air fresh while keeping the home airtight.
On the flip side, though, both HRVs and ERVs are only effective in airtight homes. If your home has gaps and cracks that facilitate air leakage, neither of the appliances will benefit you much. All the gains made at the HRV or ERV will be lost at the wall cracks and gaps.
Heat Recovery Ventilator Maintenance
HRVs don’t require much maintenance. Once the unit is installed, it will run without much trouble for most of the year. You only need to remember two things;
- Filter change: The HRV filter must be replaced every six or twelve months for optimal performance. Otherwise, the filter may become blocked, making air movement in and out of the house difficult. Additionally, a compromised filter may not effectively trap the unwanted elements in the indoor-bound air.
- Maintenance in freezing weather: When it gets freezing, such as in the winter months, the HRV system, especially the duct pipes leading into and out of the house, can freeze. You need a few sophisticated tools to prevent or tackle the freezing.
Heat recovery ventilators (and energy recovery ventilators) can be valuable HVAC additions to most homes. The two appliances boost indoor air quality and can even help with heat and moisture retention depending on the weather.
If currently working on the airtightness of your home and wondering how to do it while maintaining indoor air freshness, you just got your answer.