What is Wrong with the ERV?

No air was coming through the vents. I noticed it getting stuffy when we kept the house closed up because of smoke from the huge wildfires in the west. I thought the filters just had to be replaced and the screens cleaned and it would work again. But it didn’t work! So I bought an air flow meter and tested the air coming out and going into the ERV. Although I am not sure the meter is accurate it appears to be exchanging air at 500 cfm which is what the manual would expect.

Meter Reading
Meter Reading

I took apart the ductwork where it had misaligned and reconnected it using screws and tape. I had used flex for some of the joints and the flex had allowed the unit to move about half past direct airflow.
I realized that the large 10” tee was drooping and I could not lift it back into position. So I decided to remove it. I’m in a very cramped space to get this done and the attic is hot. But I was able to remove the duct screws and tape and the large duct tee.

Offset ERV Tee
Offset ERV Duct Tee Location


Air was coming out of the duct just fine so it occurred to me to shorten the duct and see if I got airflow. I needed to purchase an 8” elbow and I also bought an 8” tee thinking it was shorter and I might be able to get it lined up better with the long duct but I did not end up using it.
But first I wanted to try the elbow alone. That meant I had to extend the existing duct about 12”.
I couldn’t stretch it but after I attached a new collar and the elbow and I screwed on the 10” to 8” adapter I was using the original flexible duct was long enough. Screwing all those pieces together and taping them in that tiny space was time consuming. I tested the airflow and it looks reasonable although seems like a lot of CFM loss for the approximately 8′ duct. The lower duct is about 14′.

Closest Duct Airflow
Closest Duct Airflow
Furthest Duct Airflow
Furthest Duct Airflow

I’m not sure if the airflow has slowed or if the filter pads and ductwork are more clogged but at least now ERV filtered air is cycling into the house again if not all the way to our bedroom.

I decided to purchase new air filters to replace some of the old ones I had been washing in the washing machine to clean them. But when I attempted to get in contact with the Ultimate Air company in Ohio the 800 number was disconnected and the direct number not taking voicemail.

I asked my original vendor, Todd Collins from AE Building Systems and he said sadly production was shut down due to Covid and he was not sure they would resume. The website does not say they are not available but the “contact us” forms yield no information. My info email was not answered. This is a really unhappy situation. It’s bad when a small United States manufacturer has to stop production and maybe even go out of business.

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