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Community and Q&A

Basement Air quality – ERV + Dehumidifier OR Dehumidifier with fresh air?

alex_garland | Posted in General Questions on

My house, built in 2015 in northern New Jersey, features a basement with a foundation made of Superior walls (prefab in a factory and installed like Legos). Due to a high water table, I have two sump pumps installed. The basement is located underground and has three windows, each measuring 32″x14″. The only true exit is through the stairs leading to the main floor. For climate control, the basement has its own dedicated HVAC unit.

Initially, I wasn’t using the HVAC system constantly since I wasn’t always in the basement. Unfortunately, this led to the growth of mold and mildew beneath my area rug and couch. I’ve since discarded those items, thoroughly cleaned the space, and added a standalone dehumidifier. I now maintain the HVAC at 73 degrees with a relative humidity of 45%, and I haven’t encountered any mold issues since then.

However, the air quality still leaves something to be desired, as I’ve noticed stagnant odors when I’m in the basement especially in the stairwell to the basement. To get a better understanding of the situation, I invested in an air quality monitor which revealed CO2 levels exceeding 1300 ppm; all other readings appear satisfactory. While I occasionally open the windows to allow for better air circulation, I’m hesitant because this lets in outdoor humidity, and I don’t do this daily.

I’m eager to enhance the air quality and eliminate the need for the standalone dehumidifier. I’m currently considering two options: an ERV paired with a dehumidifier, or a dehumidifier with a fresh air intake. I’m seeking guidance on which option would be best.

The finished basement spans approximately 1200 sqft and serves as a playroom, gym, and TV room with a bathroom that has a exhaust fan. Although it seems relatively airtight, on windy days with the windows open, air leaks from under the basement door and reaches the first floor. To prevent this stale air from moving upstairs, I’m contemplating the use of an ERV to equalize the air pressure in the basement. However, I’m also wondering if I might be overthinking the situation.

Option 1: Santa Fe Ultra 70 Dehumidifier + Broan SKY ERV 102 CFM
Installation: This setup involves a dedicated return, channeling stale air to the ERV where it mixes with fresh air before being vented outside. Subsequently, the fresh air is directed through the dehumidifier and into the supply of the HVAC system.
Question: Can the ERV and HVAC run simultaneously with this configuration, or should it be one or the other?

Option 2: Santa Fe Ultra 98 Dehumidifier with Fresh Air Intake Port
Installation: Similar to the first option, this setup also employs a dedicated return for stale air, which is mixed with fresh air from the intake port before being directed into the HVAC supply.
Concern: Positive Pressure will push stale air to first floor.

I appreciate any insights and suggestions you may have regarding these options. Your expertise will be immensely helpful!

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