Is it better to combine an ERV with an air handler or ductless mini-splits?
We’re building a tight house (the Passive House metric of .6 ACH is the goal) with a significant amount of insulation (slab to attic R-values: 16-20-38-65) in the Chicago suburbs. Our house will be about 1,550 sq. ft. of finished space, single story, 2-BR, 2 bath, with a full basement.
I always assumed the HVAC system would be a basic combination of ERV and ductless mini-splits (for heat and AC), but our HVAC contractor is suggesting the following set-up:
Goodman air handler with 15K.W. Heat strips, for supplemental demand
Goodman 2 ½ ton Heat Pump 14.0 seer
Honeywell ERV 70 CFM Ventilator
He believes this set-up will avoid cold spots in winter, and be more comfortable on the hottest summer days. He’s considered an HVAC guru in the Chicagoland area (both commercial and residential), so I’m reluctant to disagree with him (What do I know?).
Building Science Corp. has an article on their website: Info-611: Balanced Ventilation Systems (HRVs and ERVs) http-//buildingscience.com/documents/information-sheets/info-611-balanced-ventilation-systems
The article details the most common HVAC set-ups for HRV/ERVs, and, based on the diagrams of various configurations, I can see why the use of an air handler could offer significant benefits in regards to overall comfort.
Any HVAC designers/installers see a problem with his set-up? Any serious energy penalty with his set-up — we’re trying to lower demand as much as possible in order to justify adding solar on the roof?
Any homeowners out there happy or miserable with a similar system, or with a basic ERV and min-split set-up?
What questions should I be asking?
I’ve read a few HVAC horror stories about tight houses recently, so I want to avoid a system that’s too big for actual demand, or — God forbid — mold problems because a system fails to properly handle moisture and humidity.
Any input or suggestions would be greatly appreciated. Thank you!