Existing air exchanger dying? HRV or ERV for the swap

Replacement path A — like-for-like HRV

Choose when the old unit was an HRV, bedrooms still fog, and RH sits high in January. We correct balance issues the old install never finished, refresh hoods if rotten, and haul the carcass.

Replacement path B — switch HRV → ERV

Choose when Apple Valley sealing projects (common on 90s family two-stories) turned the house arid. Cloning HRV would keep dumping moisture you no longer have. Document static shocks and sub-25% RH.

Replacement path C — switch ERV → HRV

Less common, but real: an ERV hung in a house that still runs muggy after showers and shows glass fog. Moisture rejection becomes the priority again.

First-time install (no existing box)

Skip paths A–C language. We size outdoor air for your planned-suburb envelope and pick HRV vs ERV from symptoms the same way — fog vs desert — then price penetrations that replacement jobs sometimes reuse.

What "dying" looks like on Apple Valley jobs

Homeowners usually call when the cabinet rattles, the core ices into a brick, filters were never sized right, or a finished basement closed the only outdoor-air path the 2000s install relied on. Sometimes the unit still spins but bedrooms smell stale — under-ventilation after sealing is as much a failure mode as a seized fan.

We treat replacement day as a decision day: keep the moisture mission (HRV), flip it (ERV), or reverse a prior mismatch. Cloning the data plate without reading January RH is how iced cores return for a second funeral.

Why Apple Valley replacements cluster now

Family housing from the planned-suburb decades hit renovation waves: finished lower levels, window packages, kitchen opens. Those projects closed infiltration paths the original exchanger was sized around. Units that "worked" in 2008 ice or under-ventilate in 2026.