HRV – Heat Recovery Ventilation System
Q. What is my HRV system for?
A. Your HRV system exhausts the warm humid air from your home, and exchanges it with fresh drier air from the outside. The HRV core warms the incoming air before it is distributed throughout your home. It’s important you understand how the HRV system works to control humidity in your home as it is essential for good health and prevents damage to furniture, and flooring. Watch our web clip below for more information on this topic.
Did you know? We recommend all homeowners purchase an inexpensive hygrometer to monitor the humidity levels in the home. These can be purchased online or at a local building supply store.
Q. What setting should I run my HRV control unit at?
A. For all new homes; we recommend that you set your HRV control at the intermittent auto setting which is 20 minutes on / 40 minutes off. Your HRV system can be shut off during the summer and warmer weather when you’re running your air conditioner.
Anytime one of the timer buttons is pushed (in the bathroom or kitchen) – the HRV will jump up to high speed for that period of time pressed on the button – e.g. when you take a shower and press the button for 20 minutes. After this period it will then return to the intermittent cycle.
We recommend that you only use the minimum or maximum settings on your HRV control temporarily to fix a problem or address a situation and then go straight back to intermittent auto setting.
On Minimum Cycle – your HRV will exchange fresh air with the outside continuously (24/7) on low speed. When an exhaust button is pushed in a bathroom or kitchen this will increase to high speed for the set time and then fall back to low speed.
An example of when you would set your unit to this would be if you were entertaining and had a house full of people and it felt stuffy. This setting gives continuous air exchange and fresh air.
On Maximum Cycle – your HRV will exchange fresh air with the outside continuously (24/7) on high speed.
An example of when you would set your unit to maximum would be if you were cooking and had excessive humidity or food odors or smoke that you wanted to expel.
Q. My HRV system is set at intermittent auto setting and isn’t turning on, what should I do?
- Check that the filters are not plugged (watch our web clip for information on how to clean your HRV filters).
- Check that your hood outside is not blocked as sometimes frost or even a plastic bag can prevent air from entering or leaving the home and cause issues with your HRV system.
Q. Why is my HRV system running constantly when it is set on intermittent?
A. It could be that the HRV manual override button, which is located on the left side of the actual unit in your basement, may have been turned on accidentally. If there is a green or amber light on the left hand side of the unit, keep pressing the button until there is no light on. This switch is the manual override button that is used for a technician to be able to service or work on your unit and should always be switched off.
Q. What is a humidifier unit and what is it used for?
A. While your HRV system removes humidity from your home, a humidifier adds humidity. As cold temperatures set in, humidity levels in the air will drop. Cold air is unable to hold as much moisture as warm air. Because of this, when you heat your home the relative humidity levels can drop to as low as 10%. This can lead to drier skin, as well as nose and throat discomfort. It can also cause static electricity, and dry your furniture and flooring out. A comfortable humidity level is usually between 35 – 45 %.
Please note that during the extreme cold weather like we experience in Saskatchewan, a humidity level below 30% may be required on some days to minimize condensation issues in your home.
Q. We have woken up and have moisture on our windows and on door locks, what should we do?
A. The most common cause is that you may have forgotten to turn down the humidifier or need to adjust it to align with the outside temperature. Take a look at the setting on the control panel above the humidifier and turn down the setting until the weather warms back up again. It may also mean that you need to run your HRV system on a higher setting for a day or two to fix the humidity issue in your home.
Q. How do I maintain my HRV system?
- Every three months, open the door of the HRV and remove the 2 foam filters. Vacuum the filters to remove dust and then wash in lukewarm water with mild soap solution. Let them dry and reinstall with the arrows facing towards each other. This is recommended every 3 months but it is a good idea to check these filters when you are changing your furnace filter.
- Once a year, remove the core or heat exchange cell from the unit. Soak it for 3 hours in warm water and mild soap. Rinse with a strong stream of water. Let it dry and then reinstall it.