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Community and Q&A

Control Compatibility for UltimateAir ERV

New0311 | Posted in Mechanicals on

Sorry to bother people on this post, but I am wondering if some could act as an ERV consultant for Ultimate Air since they seemed to have gone under during the pandemic and have not responded to phone calls or emails in the past 6 weeks.

I recently installed my ERV that I purchased this spring and am trying to replace the Ultimate air wall control dial with a Tekmar 563 (suggestion by the wonderful Tekmar customer service team).

I have been trying to verify this will work with Ultimate air but who knows what’s going on with that outfit…..

So my question is

Can the ERV be controlled from a set of dry contacts?  That is what the 563 uses to turn the ERV off and on.

Please note that the relay contacts are only rated for a maximum of 30V and 2A.

Cheers boys and girls

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  1. this_page_left_blank | | #1

    Why are you replacing the standard control?
    What does Tekmar say about the questions you're asking? They recommended it, so they must have some thoughts on the matter.

    Only speaking in generalities, but usually the control for something like this is a low voltage, low current device that is either communicating data to and from the device itself, or in a more simple system controlling relays on the device. The current driving the fans isn't usually flowing between the wall control and the device.

    I just took a look at the DX200 manual. The connection to the wall control is an ethernet connection. To me this indicates it requires an intelligent controller, not just a simple switch type controller. And I just looked up the Tekmar 563; they describe it as a thermostat, but do list HRV/ERV as an application. I'd still say Tekmar are likely to be the most qualified to guide you.

    Ok, last edit. After reading a bit more in the DX200 manual and the 563 manual, it looks like the only way these are intended to work together is if you have it set up as part of a furnace or air handler system. See page 28 of the DX200 installation manual and page 6 of the 563 manual.

  2. Expert Member
    Akos | | #2

    The Tekmar is a standard two stage furnace controller. Not sure why you would use it for something like this.

    The ERV has standard dry contact input for boost. This means you can turn on the unit on low (default when it is plugged in) and use a timer switch like this for boost controls:

    Not very very high tech but it works. There are probably some nicer digital countdown timers out there if you do a bit digging.

    For most ERV/HRV factory controller is your best and simplest option. I've done my own controls with a PLC and external sensors but it is not worth it.

  3. New0311 | | #3

    Thank you all for the informative responses, this is a great source of knowledge and I'm sorry to have to turn to you guys on the weekend.

    I was trying to have more than one control for the ERV since the wall dial is upstairs. I have tried to be in contact with ultimate air to order another wall dial but I have given up after 6 weeks of no response. I was told by Tekmar that the 563 works with ERV units but was unsure if it is just with the boost functions or could it control low med hi fan speed.

    Reading the 200dx manual it sounds like Dry contacts can be used, you use the F1/F2 interface as described in the manual.

    These are 24 VAC line and Return inputs.

    I'm just not sure the Tekmar 563 is the way to go for 250$

  4. New0311 | | #4

    This is wall dial

  5. Jon_R | | #5

    The unit's speed can optionally be controlled by a 0-10V DC signal. Which is easy to parallel (ie, multiple wall dials).

    Or use a single 0-10V wifi control from anywhere with a smart-phone.

    1. this_page_left_blank | | #6

      You can't have variable voltage sources in parallel. One will be dictating the voltage, overriding the others. You're at risk to damage one of those sources as well, if one is putting out 10V and another in parallel is trying to pull it down to 2V. The 0-10V input is there for closed loop control of the ventilator based on some condition, most likely CO2 level. CO2 controllers typically have a 0-10V output, whereas a wall switch or dial usually won't. I wouldn't be surprised if the DC has multiple 0-10V inputs, but they would each be wired to an individual controller, not in parallel.

      1. Jon_R | | #7

        Yes you can, just add diodes. Preferably a Schottky to minimize the loss of range. The ERV speed will be determined by the higher setting.

        1. this_page_left_blank | | #9

          "The ERV speed will be determined by the higher setting"
          I don't see the value in such a setup. This would be akin to having two light switches in parallel, such that the light is on when either one is on.

  6. Expert Member
    Akos | | #8

    ERV is one of those things that is fun to mess with in the beginning, but once up and running, there is no need to adjust anything. Keep it simple.

    About the only control I regularly use is boost when cooking or to clear wet dog smell.

  7. New0311 | | #10

    Good info...... to summarize it seems like a single wall control is the only way to go besides the 0-10 dc which is a little over my head.

    Thanks guys

    1. Expert Member
      Akos | | #11

      Almost. You do want a countdown timer on the boost input (the simple mechanical ones are fine). This should be in your kitchen, this is a control that I regularly use.

  8. New0311 | | #12

    Yes I installed those

    Just a general question now

    Are ultimate air ERVs good quality? I'm a little nervous/upset that I just invested a good chunk of my hard earned cash in a company that seems to have gone under.

    Thanks again guys for you're inputs

  9. jackofalltrades777 | | #13

    Looks like UlitmateAir is a victim of the pandemic shutdown. The company has shut down and never reopened after the COVID19 shutdown. Hopefully someone buys them out and reopens it but not sure how and when that will happen.

  10. New0311 | | #14

    Jason morosko got back to me and said ultimate air is 50-50 coming back, I wish them luck

    I could not figure out a way to control ERV with a thermostat and had to resort to single wall dial

    Thanks for help guys!

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