Should I use my HRV/ERV in the summer?

Should you run your heat- or energy-recovery ventilator (HRV or ERV) in the summer?  The answer depends on your home’s air conditioning system, your ERV wall control, the outdoor temperature and, most importantly, the outdoor relative humidity.

As a rule of thumb, if you are more comfortable outside than inside your house, you should run your air exchanger in the summer.

First, let’s talk about ERVs.  An ERV works by exchanging your indoor air with fresh outdoor air, while recovering part of the heat and moisture difference in the airstreams.  Simply put, your ERV keeps the heat and humidity where they are. In summer, the heat and humidity are outside and your ERV will keep most of it from getting inside with your ventilation air.

If your indoor air and the outside air have about the same temperature and relative humidity (for example, if you keep the windows open), there is really no need to run the ERV in order to have good indoor air quality.

However, if you have air conditioning and the indoor air is cooler and dryer than the outside air, it is generally a good idea to run your ERV intermittently throughout the day.  Assuming you keep the windows closed while the AC is running, you’ll be needing fresh air to prevent CO2 buildup and to avoid that stale “airplane cabin” smell.  You can run your Aldes ERV intermittently depending on your wall control:

  1. Manual dehumidistat: Keep the dehumidistat set to OFF. If you have a timer wall control, you can use it to periodically run the ERV when the house is occupied, especially just before going to sleep.
  2. Mode control:  Set to OFF and use the timer as described above.
  3. Speed Control: Select the intermittent setting (20 minutes low speed exchange followed by 40 minutes off).
  4. Digital multifunction control: Select ECO 2 mode (20 minutes low speed exchange followed by 40 minutes off)
  5. Electronic Humidistat with LCD: Select the intermittent mode (20 minutes low speed exchange followed by 40 minutes off).

Running your ERV to get fresh air instead of opening the windows will have the added benefit that the incoming warm air will be partially pre-cooled and dehumidified thanks to the energy-recovery core.  The air conditioner will not have to work as hard to bring the fresh air to your desired temperature.

What about HRVs? If you have an HRV (heat-recovery ventilator) rather than an ERV, the only difference is that the humidity in the outdoor air will pass through the HRV core without any moisture transfer, and the cooler indoor air may feel damp (because cold air has less ability to contain water vapour than warm air).  You may consider using a dehumidifier in addition to the air conditioner.

How can you tell if you have an Aldes HRV or ERV?  Just have a look at the model number: if it starts with an “E”, you have an ERV; if it starts with an “H”, it’s an HRV.

In order to maximize your house’s indoor air quality and consequently your health, you should take every opportunity when the outdoor conditions are comfortable (for example at night) to run your air exchanger.



Go Cordless with InspirAIR® Compact

The InspirAIR Compact line of HRVs and ERVs for multi-unit residential buildings is now ready for hard-wiring applications.  All units can be ordered with an ETL-approved junction box instead of a power cord and plug.  So now engineers and installers have the option to bring a conduit directly to the unit, instead of having to install additional receptacles and face-plates to accommodate the plugs.

The new models are:

  • H80-HF-N: HRV with exhaust defrost
  • H80-HR-N: HRV with recirculation defrost
  • E80-HF-N: ERV with exhaust defrost
  • E80-HRG-N: ERV with free cooling
  • E80-HRX-N: ERV with EC motors and free cooling
  • E130-HR-N: Larger capacity ERV with recirculation defrost (and mirror version E130-HR-N-M)

New spec sheets and installation manual are all available online now. Contact your account manager or for more information.


Discover the new version of Selector!

Find and configure the ideal HRV/ERV for your project with the new version of Selector!

Finding the product that meets your needs doesn’t need to be complicated! You aren’t sure which model is best suited for your commercial project? Try our selection software to save time!

The latest version of the software is now available for download HERE. Please note that it is an executable file (.exe) and is only compatible with the Windows operating system.

Once the software is installed, start the Selector and fill in your contact information. Enter your e-mail and click the button marked “get registration key by e-mail”. Do not close the program.

Check your e-mail to find the key. Return to Selector and enter the registration key. Click “Key Validation” to activate your copy of the software.

InspirAIR Commercial Launches!

Get inspired — and inspire confidence in your customers — with brand new InspirAIR Commercial indoor and outdoor heat- and energy recovery ventilators!

This product line was created with the needs of the construction industry in mind: competitive prices, short lead times, and offering a wide selection of options to fit the requirements of the majority of building designs.

The latest version of our Selector software allows you to create projects including InspirAIR Commercial. Download a copy or update your existing software by clicking “Check for updates” on the initial screen.

With four models covering airflows between 500 and 4000 cfm, and four types of AHRI-certified air-to-air heat recovery technologies, InspirAIR Commercial has the flexibility you require, and is easy to select and configure using our Selector software and Revit families.

Among the new features are:

  • Air exchangers with enthalpy wheels and EC motors for 500 to 4000 cfm. And with smaller cabinets than the current Low Profile series!
  • Bypass damper option for operation in economizer mode, without needing to connect additional ducts or components outside the units.
  • Bigger airflow ranges for each model, allowing you to maximize heat-recovery efficiency. For example at 1500 cfm, you can choose between three models (P15, P20 and P30) depending on your target efficiency requirements.
  • Standardized dimensions for the cabinets and the extensions for bypass channel and pre- and post-heating coils.
  • Revit families available for engineers.

We invite you to check out the full set of technical specifications.

The InspirAIR Commercial will be replacing the Standard series and the Low Profile wheel models over the course of 2019:

  • 05-Feb-2019: Quoting opens for InspirAIR Commercial.
  • 22-Feb-2019: Last day to issue new quotes for Standard series and LWxxxx models.
  • 19-Jul-2019: Last day to place an order for Standard series and LWxxxx models.

Training sessions will be announced in the coming weeks. Please contact your account manager or one of our technical sales representatives for more information on this exciting new product family!

New version of Selector software is now available!

Selector saves you a lot of time when choosing the right commercial HRV/ERV.

Just select your airflow requirements, design conditions and other criteria, and Selector will propose one or more product models that meet your needs. Then you can generate a submittal PDF with all the project details for quotes and approvals.

The new version now includes the new InspirAIR Commercial range, new Light Commercial HRVs and ERVs, new coil calculations, and many bug fixes.

If you are already using Selector on your Windows device, all you need to do is start it and click on the “Check for updates” button on the title screen.

If you do not already have a copy, please download the installer. Please note that it is an executable file (.exe) and is only compatible with the Windows operating system.

Once the software is installed, start the Selector and fill in your contact information. Enter your e-mail and click the button marked “get registration key by e-mail”. Do not close the program.

Check your e-mail to find the key. Return to Selector and enter the registration key. Click “Key Validation” to activate your copy of the software.

Does my Heat Recovery Ventilator (HRV) have a problem?

Does my Heat Recovery Ventilator (HRV) have a problem? Do you have condensation in your windows?

No, your HRV is not the problem.
An HRV is an effective, energy-efficient and healthy method of managing moisture in your home in the winter, but your HRV does not remove condensation from your windows, it removes excess moisture in the air.

If condensation forms in your windows, it is because the temperature of the surface of the window is lower than the dew point of the surrounding air. There may be several reasons why the window temperature is below the dew point of the air such as poor window quality or too high a dew point.

The condensation in your windows is the same as the condensation that forms on a cold beverage can on a hot, humid summer day. The surface temperature of the can is lower than the dew point of the air outside.

The dew point of the air depends on the amount of water vapour in the air. The higher the relative humidity, the higher the dew point and the more condensation will occur at high temperatures. For example, air at 21°C and 40% relative humidity has a dew point of 8°C.

All surfaces with a temperature of 8°C or less, such as a window, will become covered by a layer of water droplets.

To eliminate condensation in windows, there are two solutions.

  • Lower the dew point of the surrounding air, or
  • Increase the temperature of the window surface

To lower the dew point

Your HRV is the perfect appliance for lowering the dew point of the air when it is cold outside.  Your HRV will evacuate moist, stale air from your home and replace it with fresh, dry air from outside, lowering the dew point. Why is the air outside dryer? Because cold air holds less water vapour than warm air. When cold air is heated, first through the HRV and then through the home’s heating system, the relative humidity drops.

There are other technologies that can also lower the dew point of your home, for example, a dehumidifier. However, a dehumidifier does not supply any fresh, filtered air.

Increase the temperature of the window surface

The only other possible solution to eliminate condensation in the windows is to increase the temperature of the inner surface of your windows.

Window panes are exposed to very large temperature differentials in the winter. Some windows are better than others at preventing heat loss through transmission. For example a single pane will have almost the same temperature on the inside surface as the outside surface, whereas triple pane windows with air gaps will provide more insulation and significantly reduce heat loss, meaning the inside surface temperature will be closer to the room temperature.

The most effective method for increasing the temperature of the inner window surface is to promote air flow across it. Window treatments, such as curtains or blinds, create “microclimates” near the window and lower the surface temperature, which helps to form condensation.

To promote air circulation near windows, you can:

  • Open the curtains and raise the blinds
  • Use a fan to blow air toward the windows
  • Place a heat source under the window

If your windows are very old and need to be replaced, energy efficient windows (such as triple-pane) will also help ensure the interior surface temperature of the window is higher.  Regardless of the quality of the window, if a “microclimate” is created on the window surface due to a lack of air movement, there could still be some condensation, depending on the outdoor temperature and the indoor dew point.

Are Bathroom Fans Obsolete?

The residential ventilation strategy of using an HRV and ZRTs to ventilate bathrooms, instead of using individual bathroom fans, is more cost effective for the builder and for the home owner. Not only is the initial cost of the equipment and installation less expensive: the operating costs are lower as well.
Rather than installing energy-wasting bathroom fans that require individual ducting, it is more advantageous to install zoned exhaust terminals that direct the ventilation capacity of the HRV to the right place at the right time, while recovering most of the heat in the exhaust air.
And there are many other advantages to our approach:

  • Tighter building envelope and more attractive home exterior (fewer penetrations)
  • More balanced ventilation, avoiding negative pressure
  • Quieter operation
  • Avoids user error of leaving the fans on for extended periods

Please check out our new video and go to the Aldes Professional’s Zone (or contact your sales representative) for a copy of our White Paper that shows in detail how Aldes HRVs with ZRTs are winning combination.

Autumn is HRV Maintenance Season

Across Canada, heating season is fast approaching. While it is still warm out, it’s an ideal time to open up your HRV and do the annual maintenance: clean the heat-recovery core, wash or replace the filters, and ensure that the drains are clear of any blockages. Our new and improved residential installation and maintenance guide offers many helpful tips for maintaining your HRV and keep healthy air flowing through your home during the winter months.

If you or your clients have an older HRV that is inefficient or is no longer functioning, Aldes HRVs are an easy choice for a replacement. Our compact top port units can hang in the same place as the old unit and connect up easily with flex duct to the existing ductwork. In many cases you can even connect the existing wall controls to the Aldes HRV without re-wiring. Contact us and we can help you assess whether your existing HRV can be replaced with a new Aldes ENERGY STAR® model.