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HRV With Integrated Zoning for Spot Bathroom Ventilation

MStaudaher | Posted in General Questions on

Re: Aldes Vent Zone IAQ with heat recovery combined with zone register terminals. I was reading a GBA article that mentioned this HRV with integrated zoning for spot bathroom ventilation.  Does anyone have any experience with thsi brand and this specific product?  Is it a good HRV and does the zoning mechanism make reasonable sense to boost ventilation for specific bathrooms instead of simply boosting the ventilation rate for all baths?

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  1. GBA Editor
    Martin Holladay | | #1

    I'm hoping that a GBA reader who has installed this product can provide feedback.

  2. Jon R | | #2

    It may also make sense to boost ventilation to bedrooms at night and turn it down/off during the day. Prices don't look too bad.

    It should also be possible to use other ERVs with standard power zone dampers.

  3. MStaudaher | | #3

    I called the company and spoke to one of their reps. Unfortunately the motors they use in their ERV/HRVs are PSC motors and not ECM motors. The reason that this individual control technology is apparently not offered by other manufacturers is because ALDES has a patent on it.

    They sell the ZRT terminals separately, but it’s not clear to me if you could connect them to another brand of ERV/HRV to initiate a boost function when they are individually activated to increase spot ventilation in a bathroom.

    The benefit of this type of system seems to be the fact that you could significantly increase ventilation to individual bathrooms on demand without having to increase return flow from all other returns simultaneously. You also wouldn’t need to have such a large ERV/HRV to obtain the needed increased flow to exhaust air from a particular location.

    If anyone has wired one of these ZRT terminations to another HRV or ERV I would appreciate any information you could provide.

  4. Tom K. | | #4


    Have you made any progress on this? I am planning to do the same type of install if I can solve the control issue. I won’t buy an ERV/HRV unless it has ECMs. Aldes sells the ZRTs with both 24 and 120 VAC wiring. The problem is that most ventilation systems don’t keep track of which switch called for boost. I bet a few relays could be used to trigger the correct zrt to open. Maybe just run a 4 wire Tstat wire from ventilator to switch and then a 2 wire from switch box to zrt. Put the relay on just before the ventilator which controls power to the extra 2 wires going back to the switch box and on to the zrt.

    Depending on current draw of zrt you might be able to get it wired without dedicated power but I’d want to look at the specs on the ventilator and switch first.

    1. MStaudaher | | #5

      I am moving forward. I am installing a Broan 250TE ERV and connecting it to the ZRT-2 terminals which will be located in the bathrooms and the laundry room. The HVAC contractor is using the 120V ZRT-2 terminals and is planing to control them with a relay.

      1. Tom K. | | #7

        Nice. That Broan 250 has some great stats. I am thinking about waiting for the fan tech hero ERVs to come out which should be in the next 10 months or so. I’ll go with the HRV if my humidity is uncontrollable this winter. I wish they had more units with swappable cores.

      2. Jordan H. Zone 6 | | #8


        I know it's been a while, but I am planning on doing almost the exact same installation you noted above. Looking back, is there anything you would have done differently, or did the 120V ZRT-2 terminals with relays work well with your Broan 250TE ERV?


        1. Tom K. | | #9

          I’m still waiting for that Fantech hero erv which may never happen. I’ll probably go with the broan as well. I have all 4 of my 120v zrt’s installed and waiting. It’s great to be able to use any commercially available timer with these. The zrts have a micro switch that closes a circuit when the door swings open so it should be easy to control any erv or hrv as long as they have a boost control terminal. I already have my wiring in place as well as my ducting to the outside. Just need to build a plenum to combine the 4” ducts to 6”.

          Good luck with your project. If you are installing a zrt in the attic make sure to insulate the heck out of it. I made a XPS box from 2” foam scraps that wraps around the zrt then used canned foam to get in all the tricky areas.

  5. Matt F | | #6

    Don't assume ECM ERV will use less power than and PSC motor one. You need to look at the fan/power curve or table and see where you are at.

    A Renewaire EV90/EV90P with PSC motors will use 46w at 90CFm, .25" static, while a Panasonic Intelli balance 100 will use at least 54w (and probably a bit more) under the same conditions.

    A PSC motor ERV also doesn't need any control tie in to boost the exhaust (it may be unbalanced boost), just a drop in static from the zone damper opening. You do need to design the duct system to have it work correctly.

    The downside of these flow regulators is that they have a .2" static requirement, which consumes some energy continuously when using an ECM motor.

    MStaudaher, are you going to run "boost" in the laundry room? If you are not, you put a CAR-II in there.

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