ERV With Boost Mode for Bathroom Ventilation
There have been a few posts here on GBA throughout the years on HRVs and bathroom ventilation, and a few posts about using an Aldes ERV that provides boost switches and mechanical dampers for each bathroom.
We’ve got quotes for ERVs at the home we’re building in CT, and they all use Broan units. The Broan units are well-reviewed but don’t let you ‘boost’ the bathrooms. Guidance is also unclear on whether you should be driving super humid bathroom air through the ERV at all.
I’m trying to avoid unnecessary penetrations in the house for things like bathroom exhaust fans if they can be avoided, but has anyone actually used an Aldes system successfully? Or has anyone used a Broan/Panasonic ERV in combination with bathroom exhaust fans and can reassure me that it’ll all be OK? 🙂 Thanks!
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If you search around you will find other questions and threads with differing options on this.
The Aldes system is brilliant in theory, but there hasn't been a user report of it on GBA on it.
Otherwise boosting boosts all bathrooms rather than just the one you are in.
Boost is a pretty standard feature on ERVs now. Which model are you getting? Broan AI has boost. If you go without exhaust fans, get the largest ERV model you reasonably can that has boost. As a small bonus it will run more efficiently at lower speeds.
What exactly do you mean by "in combination"?
I have a 210 cfm broan ERV and utilize the humidity sensing boost control for bathroom humidity. I like that I can program the exact cfm I want the boost function to utilize. From what I read it's fine to utilize it in place of a bath fan as long as the erv runs continuously vs intermittent which could leave large amounts of moisture in ductwork. My wife's initial complaint was that the erv boost function worked too well so I had to dial down the cfm so she could keep more moisture in the shower.
I would also like to hear of any users’ experience with the Aldes exhaust system. I am considering installing that myself.
I'm also interested and will add here rather than starting another very similar thread. I'm a bit colder (CZ 6b) and want much the same: ~ 20-30cfm as 'baseline' (only my wife and I); boost for 2 baths, and max flow about 150 cfm. Current top contenders (high SRE, reasonable cfm/W) are Panasonic Intelli-balance 200, Broan AI 210, and RenewAire Premium M. The min flows could be accomplished via timer (e.g. 20 min/hr), and I'd like ability to add a CO2 or use a humidity sensor for a bath. Are there differences the controls, noise, longevity, or other capabilities to know about? The Panasonic sells for ~$1000 more than the others - is it worth it? We originally considered the smaller Panasonic - one for upstairs, and one down. That's still on the table but less appealing due to wall penetrations and my desire for a wildfire (smoke) air filter on the intake.
We put in two Panasonic Intellibalance 100s, one for each floor, each independently ducted, with Swidget boost switches in the bathrooms, which allow for manual timer and/or humidity boost control. Seems to be working fine so far.
Any updates to this thread? I too am considering using the Aldes system and have so far doubled down on combining ventilation with bath exhaust.
I will say, in response to @graygreen, that you don't have to boost all bathrooms. Aldes makes a ZRT unit - zone register terminal. It is basically a motorized damper with a smaller opening in the flap, which allows for continuous ventilation and increased, location specific exhaust when the damper is triggered to open.
It appears that it can be controlled independently of the HRV or ERV, which is what I will do if I choose a recovery ventilator from another manufacturer. Adding the signal to boost the ventilation flow could be accomplished with a separate signal from for instance a humidity sensor to the ERV, or in tandem perhaps from the same sensor that activates the ZRT.