New build: Is it an issue relocate Return Air from downstairs wall to upstairs ceiling?
I am building a new double-storey house in Australia. Due to a structural clash with a skylight, the builder wants to relocate the primary Return Air (RA) vent. It was originally designed for the ground floor, but they now want to move it to the upstairs hallway ceiling, right outside the bedrooms.
The unit is a Model: Actron Advance ducted reverse cycle Multi Zone CRV240T/EVV240S (24kW) and it will be installed in the roof space.
The builder’s comments:
- Air Resistance: Since the unit is in the roof, moving the RA upstairs creates a shorter, straighter duct run, which they claim improves airflow across the fan coil.
- Sensors: They argue that because the system uses individual zone sensors, the physical location of the RA won't affect room temperatures.
- Acoustics: They claim the duct length is sufficient to absorb suction noise, despite being right outside bedroom doors.
Mixing: They admit a ground floor return helps with "air mixing" but say overall efficiency won't change.
- Aesthetics are better: One trade off is that there isn't a return air downstairs near the entrance so it will look better.
My concerns:
- Air stratification: Since heat rises, will an upstairs-only return struggle to pull cold air off the floor downstairs during winter? I’m worried about the ground floor feeling "stale" or "stuffy."
- Noise: Is it standard practice to put a large RA intake in a quiet bedroom hallway?
- Maintenance: The filter will now require a ladder in a narrow upstairs hallway rather than easy access downstairs. Probably not too much of an issue because I am told I can clean the filters without going into the roof space.
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Seeking advice on: Is an upstairs-only return for a two-story home a major compromise, or is the builder right about the efficiency gains from the shorter duct run? Or is it generally okay and just accept it?
