Integrating HRV Supply/Exhaust with Ducted Minisplit System
Climate zone 5B, new construction build in process, with dedicated and balanced ventilation. I am contemplating the location and termination of the HRV interior supplies and exhaust intakes. For various reasons, the goal would be to limit the penetrations and grill trims necessary. Aside from all the clever ways to conceal duct penetrations in built in furniture, toe kicks, etc., my question is whether the HRV supplies could be integrated into the ducted mini split boots and the exhausts integrated into the bathroom exhaust fans?
For the supplies, could you have an HVAC supply boot with the appropriately sized duct connection for the HVAC and a 4″ for the HRV? Both supplies would flow out of the same grille. It doesn’t seem like there would be much potential to back feed either duct from the other, but even so, they are both supply side flows and a backdraft damper could be installed if necessary.
For the exhausts, assuming the presence of a bathroom ceiling exhaust fan for additional moisture and odor control when the bathroom is in use, could you connect the HRV exhaust intake to a Y at the fan housing? The exhaust fan duct would have a backdraft damper on it, just beyond the HRV connection, so the HRV would be prone to pull air from the bathroom area.
Please let me know what I’m missing in this approach.
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Integrating mechanical ventilation with ducted heating and cooling systems is not uncommon. Most HRV install manuals I’ve seen describe that option. Sometimes the controls can also integrate—so that the hrv runs intermittently and turns on the air handler when it needs to for example.
Here’s a manual from Panasonic depicting that—pages 10,11
It’ll be easiest to duct supply into the trunk rather than branches. And you could eliminate bath fans and just install hrv exhaust registers and boost switches.