HRV/ERV People! I have a few questions for you.

AI Hydra


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May 4, 2021
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Hi All. I have a fish room with an HRV—hooray! However, it's not working properly. The HRV has twice had moisture issues.

The first HRV issue was that moisture froze (internally and in the drain line) and then leaked once thawed. Called the proper people, they checked the unit and installed drip pan. I thought problem was solved. The second issue, which I just discovered, is that one of the insulated lines connected to the HRV is full of water (top line, left side). As a result, I think the unit stopped working since my pH has plummeted. Waiting for the repair person as I type.

It seems like the warm, humid air from the fish room and the difference between the external temperature is causing the HRV moisture problems. Because of the aquarium moisture, does that mean the room needs an ERV instead of a HRV?

Or is there some kind of air pre-treatment system that is required with a HRV? I run a HUGE dehumidifier in the room and the room humidity is 57%.

One of the HRV ceiling vents is about 3-4 ft above the tank (500g). Could that cause the moisture problems?

What else could be causing the moisture problems?

There's maybe 1000g of water in the room between tank, sump, ro/di storage, and salt reservoir.

Your help is much appreciated! I want to be able to ask the right questions when the repair person arrives.
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