- Fresh Air Systems
Frequently Asked Questions
How to replace Filters?
There is typically a minimum of two filters per unit. One filter is for the fresh air coming into the home, and the other filter is for the exhaust air leaving the home. These filters are in place to keep the heat recovery core and the blower motor wheels clean from dust and debris. Both filters are typically a foam material with a frame around them, and they can easily be pulled out from the unit to be cleaned or replaced as needed. Filters should be cleaned quarterly or every 2 to 3 months and replaced every 1 to 2 years or as needed. Filter cleaning in the winter should be vacuuming only. The filters should not get wet during winter cleaning. If returned to the unit wet, they could freeze. In the Summer, clean filters with mild soap and water and let dry before returning them to the unit. There could be a third filter on some units, like a HEPA, or a higher MERV filter that would filter the fresh air coming into the home. It would provide the homeowner with better filtration for those who might be suffering from allergies or asthma.
What is a Core?
The core is the heart of the HRV or ERV; this is not a filter. The Heat Recovery Ventilator uses a Heat Recovery Core, which recovers heat only. The fresh air entering the home and exhaust air leaving the home pass each other in the heat exchange core, allowing a percentage of the heat energy in the stale air to be transferred to the fresh incoming air, with minimal cross-contamination of the air streams. The Energy Recovery Ventilator recovers heat and moisture. Besides transferring heat energy, ERVs also take the humidity from the warm side and keeps it on the same side as where the humidity came from (Winter/Inside and Summer/Outside). An ERV keeps the Relative Humidity in the home in check and does not put an extra load on the home's air conditioning system.
How do I know what part/s to replace?
Using your Model and Serial Number of the unit, go to the exploded view of your HRV or ERV to find the correct replacement part you need. If you are not sure, have a qualified HVAC Technician service your HRV or ERV to know what part to replace.
What is the maintenance needed on my HRV/ERV?
The equipment you are servicing may be a heat recovery ventilator (HRV) or an energy recovery ventilator (ERV). In both cases, proper maintenance is critical to maintaining the much-needed fresh air, pollutant removal, and moisture control. This keeps your home safe and comfortable. Simple steps can be easily performed to ensure your HRV or ERV will ventilate and operate to its maximum efficiency.
- UNPLUG THE UNIT – Before any maintenance is performed be sure there is no power to the unit.
- INSPECT BLOWER MOTOR – Vacuum the blower wheel to remove any dirt and debris buildup.
- INSPECT INTAKE AND EXHAUST HOODS – There are two hoods outside of your home: the fresh air intake and the exhaust or stale air from home. The fresh air intake hood will be the dirtier one. Remove any buildup of debris and clean both the hoods and screens to provide maximum airflow.
- INSPECT, CLEAN, AND REPLACE FILTERS – Filters should be cleaned and replaced quarterly or every 2 to 3 months. The filters should not get wet during winter cleaning. If returned to the unit wet, they could freeze. Summer, clean filters with mild soap and water, and allow to dry before returning them to the unit.
- INSPECT AND CLEAN EXCHANGER CORE – An HRV core should be cleaned once a year, rinsing the core with water or soaking it in a mild soap solution. This should be done in the Summer only. If the core would be cleaned and wet and replaced in the winter, it would freeze. An ERV Core should be vacuumed once or twice a year, and NEVER washed with water. An ERV core is made of paper, and the core will fall apart if you get it wet.
- GENERAL CLEANING AND INSPECTION – Vacuum or use a damp cloth to remove any accumulated dirt from the lower drain pan. If you have a drain hose, make sure water will drain freely.
- CONFIRM OPERATION – Close and latch doors and access panels. Restore power to the unit and run through an on-off cycle to ensure proper operation
How often do I need to clean my filters?
Filters should be cleaned quarterly or every 2 to 3 months. Filter cleaning during the winter should be vacuuming only. The filters should not get wet from washing during the winter. If put back into the unit, wet, they will freeze. In the Summer, clean filters with mild soap and water and allow to dry before returning them to the unit.
How often should I replace the filters?
Filters should be replaced every 1 to 2 years or as needed.
How often should the HRV core be cleaned?
An HRV Core should be cleaned once a year, rinsing the core with water or soaking it in a mild soap solution. This should be done in the Summer only. If the core is washed during the winter, it could freeze if returned to the unit wet.
How often should the ERV core be cleaned?
Vacuumed an ERV core once or twice a year but NEVER wash an ERV core. ERV cores are made of paper, and the core will fall apart if it gets wet.
What control should I use with my HRV/ERV?
It all depends on how you want to operate your HRV or ERV. Most controls have basic operations of Off, Low Speed, High Speed. You can upgrade to serval control options, including a dehumidistat for moisture control, intermittent ventilation 20 minutes per hour, 7-day programable with four periods of operation per day, and a Smart Mode option to operate your HRV or ERV automatically.
Does my HRV/ERV need a control?
No. There is a button control on the HRV or ERV for basic operations; Off, Low Speed, High Speed. You can upgrade your control to improve performance.
How do I know when to replace my HRV/ERV?
If you are not sure, have a qualified HVAC Technician service your HRV or ERV to know if it is time to replace your unit.
What is the difference between an HRV and an ERV unit?
An HRV (Heat Recovery Ventilation System) uses the stale heated air to warm the fresh air coming into the home. It does this through the heat exchanger core. The warm air from the house, warms the core, and as the colder fresh air passes through, the colder fresh air is warmed and returned as tempered fresh air into the home. An ERV, or Energy Recovery Ventilation System is like an HRV and exchanges the stale and fresh air the same way. However, an ERV takes humidity from the warm side and keeps it where the moisture originated. In the winter, a percentage of the moisture is returned into the home. During the Summer, it remains outside, which keeps the inside relative humidity in check and does not add an extra load on your home's air conditioning system.
Why should I install an air exchanger?
Homes today are built tight, very tight, and generate both moisture and pollutants. We create excessive levels of moisture that can collect on our widows in the form of window condensation. These higher moisture levels can cause structural issues in the form of mold, mildew, fungi, dust mites, and bacteria in our homes. Installing an air exchanger is like having a set of lungs for your house. It inhales fresh air and exhales the bad, moist, polluted air from your home 24 hours a day. Having an air exchanger breathing mechanically for your home allows your home's Relative Humidity to be at a level that will be healthier for you and your home.