Said It Here

How to wire a third-party controller to a Vent-axia MEV unit

Connecting a third-party controller to a Vent-axia MEV unit creates confusion over whether the 0-10v ground is safely shared with AC power and how to map existing light and fan switches. This mismatch leaves installers completely lost and unable to finish wiring their ventilation systems.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Looping the 0-10v ground with the neutral
  2. 2
    Watching instructional videos
  3. 3
    Reading previous Reddit posts

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

r/askanelectrician1 person · September 2026

“Went to do the wiring and I'm lost.”source ↗

“I have a light switch and separate fan switch (not sure if that makes a difference here). I posted a picture of the new electrical and old electrical. Please help. Im an idiot.”source ↗

NovemberDeltaSH · r/askanelectrician · 4 upvotes
r/hvacadvice1 person · September 2026

“I'm looking at building a ventilation system, I want to use a Vent-axia MEV unit which has 0-10v input for fan speed control (3 step) and a controller from Aliexpress which has the wiring in the picture.”source ↗

“I can only assume the 10v Ground is shared with the AC? is this safe / an issue with noise?”source ↗

oldguychris · r/hvacadvice · 2 upvotes

Where this came up

People with this problem also raised