The Certified Install is the work done to your written scope, then the room measured again against it. The same readings taken on the Free Air Check are taken a second time, and you get the before-and-after in writing.
"Certified" here has a plain meaning. It is Little Lungs checking the finished room against the scope you approved at the design stage, not a badge from a third party. The scope said what equipment goes where, what the room should read and which building department issues the permit. The install delivers that, and the final readings show whether it did.
The order below is the order the work runs in. Each step points back to a line in the written scope.
| Step | What is done | What it is checked against |
|---|---|---|
| Permit | The permit is pulled from the authority named in the scope: LADBS for the City of Los Angeles, or the city's own building department in Santa Monica, Culver City, Beverly Hills and the South Bay. | The permit authority line in the scope. |
| Indoor unit | The head is mounted on the wall marked in the design, with the airflow aimed so it travels parallel to the crib. | The placement drawing and the make, model and capacity in the scope. |
| Line set and wall penetration | Refrigerant lines and control cable run along the agreed route through a sealed wall opening. | The line-set route in the scope. |
| Condensate | Water from the indoor coil drains by gravity where the route allows, or through a pump where it doesn't. | The scope notes which. A pump is one more thing that makes sound in the room, so gravity is preferred. |
| Outdoor unit | Set on a pad or bracket with vibration isolation, in the location marked away from the child's window. | The outdoor location in the scope and any local noise rule, such as Santa Monica's Municipal Code Chapter 4.12. |
| Electrical | A dedicated circuit for the equipment. Many 9,000–12,000 BTU single-zone models run on 115V. | The circuit specified in the scope. |
| Air and humidity | Any filtration or air purification in the plan is installed and set up. | The air and humidity plan in the scope. |
| Start-up | The system is started and set up following the manufacturer's installation instructions, and its overnight setting is chosen with you. | The manufacturer's documentation for the equipment installed. |
| Inspection | The permitting authority's inspection. California's Title 24 energy code can also require compliance documents, and in some cases third-party HERS verification, for a new or altered system. | The requirements of the authority named in the scope. |
Residential ductless equipment moved from R-410A to A2L refrigerants such as R-32 in 2026. The scope names the refrigerant the chosen equipment uses.
The Certify step re-measures the same conditions the Free Air Check recorded, in the same places, so the two sets of numbers can be read side by side.
| Reading | Where it is taken | Why it is the one that counts |
|---|---|---|
| Temperature | At crib height, compared with the thermostat | The thermostat reports the wall it is on. The crib is where your child sleeps. |
| Relative humidity | In the room | Compared with the EPA's guidance to keep indoor humidity below 60%, ideally 30% to 50%. |
| Airflow | At the supply serving the room | Confirms the air is reaching the room and travelling past the crib, not onto it. |
| Sound | At the crib position, with the system in its overnight setting | Manufacturer ratings are measured under their own conditions. This is the number in your room. |
You receive the before-and-after in writing. That record is the difference between being told a room is right and being shown it.
Most comfort problems in a child's room trace back to one of three install decisions: a unit one size too big, a head aimed across the crib, or an outdoor unit under the bedroom window. Each one is cheap to get right on paper and expensive to fix on a finished wall. Keeping design and install as two steps, with a written scope between them, means every one of those decisions is made before anyone drills.
For how sizing decides whether a mini split runs quietly or cycles, see what size mini split a child's room needs. For how it compares with the alternative, see mini split vs window unit for a nursery. For single-room price ranges, see what a mini split costs in Los Angeles. For what the finished room should sound like, see are mini splits loud?
The work is done to that scope, and the same readings are taken again. Those are the "after".
Little Lungs works with leading manufacturers including Mitsubishi Electric and Aerus Air Scrubber Plus. See all three steps on one page.
It means Little Lungs verifies the finished room against the scope written at the design stage. It is not a third-party certification. After installation the same readings taken at the Free Air Check are taken again, and you receive the before-and-after in writing.
The same conditions measured at the Free Air Check: temperature and humidity at crib height compared with the thermostat, the airflow serving the room, and the sound level at the crib position with the system running in the setting it will use overnight.
Yes. In the City of Los Angeles the Department of Building and Safety requires a mechanical permit for HVAC installations, and a single residential unit typically qualifies for an express permit with no plan check. Santa Monica, Culver City, Beverly Hills and the South Bay cities each run their own building departments.
Placement is set in the written scope with noise in mind, on a pad or bracket with vibration isolation and away from the child's window. Some cities also set rules: Santa Monica's Municipal Code Chapter 4.12 names air-conditioning equipment and sets noise limits at the property line by zone and time of day.
The Free Air Check takes the readings the Certified Install is measured against. No charge, no obligation.
Get Your Free Air CheckSources
