Energy Savers: Energy Recovery Ventilation Systems

Here is an article about the use of a heat recover ventilator (HRV) in your home.

Recently, I was called to a remodeling customers home . She complained that the doors in the lower level of the house were sticking and not able to open and close properly. The weather here in Minnesota has been very hot with very high dew points. Some days the dew points were in the 80 degree range.

The day I was called to the house was a typical for this summer-a warm and humid day. Upon entering the house, I noticed that the house was cool and the air felt humid as well. I looked at the doors and asked several questions. Yes they have been running the air conditioning, no, they do not leave doors and windows open for fresh air. I looked at the humidistat and the reading was 66% at 74 degrees- Wow!

I went to the basement and saw that the HRV was set to run 20 minutes every hour.

The HRV was bringing in 90 degree air, cooling it slightly and dumping fresh air that was full of humidity into the cool house. The air conditioning would cycle off at it's set temperature without getting the humidity out of the air.

If you live in a state where you have high humidity in the summer, turn the HRV off. The article I have linked below states that you want to leave the HRV on to bring in humidity. This would be a good idea if you live in Arizona, but not for us here in Minnesota.

We brought in a commercial dehumidifier after turning the HRV to the off position. As the humidity level drops, the doors will begin to function as they shrink down in size.

Energy Savers: Energy Recovery Ventilation Systems