Most HVAC companies size your system by square footage, fill refrigerant by gauge pressure, and skip combustion analysis because it takes ten extra minutes. We don't. Every Tru72 job is run with real instruments and real measurements, the same way the Larsell family has run it since April of 1972. The methodology has a name. It's been there for fifty-three years.
The Larsell Mechanical founding standard, written down in 1972 and never edited. Three generations of craftsmen have practiced the same operating discipline. The name changed in 2025. The way the work gets done did not.
Clean means the technician leaves the home cleaner than they found it. Quality means the install matches the design and the design matches the data. Comfort means the system delivers what was measured for, in every room.
The diagnostic-first method. Manual J before sizing. Refrigerant weighed, not eyeballed. Combustion analysis on every gas appliance. Static pressure on every duct system. The numbers, on paper, before any recommendation.
Before any recommendation, the technician measures what's actually happening in your system. Refrigerant weight, combustion gases, static pressure, electrical readings, temperature splits, infiltration sources. The diagnostic kit on every Tru72 truck is the same kit a manufacturer rep would carry: ACCA-grade instruments, calibrated, traceable.
Most HVAC reports are written for other contractors, not homeowners. Tru72 hands you the data and the meaning together. "Your static pressure is 0.94 inches of water column, which is 35% above design. That's why your blower motor wore out at year 8 instead of year 15." Every measurement gets a translation. Every translation gets a "what we'd do about it."
The install plan is built from the diagnostic data, not from a generic catalog default. Right-sized equipment from Daikin or Goodman. Ductwork modified where the static pressure showed it had to be. Refrigerant charged by weight, not by gauge guess. The homeowner sees the install plan before any commitment, and the install plan references the diagnostic numbers it was built on.
Commissioning is the step almost no HVAC contractor performs. After the install, we re-measure the system performance to confirm it matches the design. Refrigerant subcooling and superheat verified. Combustion confirmed. Static pressure logged. The homeowner gets a commissioning report alongside the install paperwork. If the numbers don't match the design, we adjust before we leave.
The ACCA-standard load calculation that determines correct HVAC sizing. Tru72 runs one on every replacement install at no extra cost.
Read the full explainer →Why Pacific Northwest homes need heat pumps engineered for the climate, and how Tru72 sizes them with Manual J on every job.
Heat pumps explained →Every Tru72 gas appliance install or repair includes a combustion analyzer reading. CO, O₂, stack temperature, draft verified.
See furnace service →Blower-door test, duct leakage, thermal imaging. Where your home is losing comfort and energy, measured with numbers.
Home performance →Humidity, particulates, VOCs, allergens measured before any equipment recommendation. The data drives the design.
IAQ assessment →Zone-by-zone Manual J on new installs. Service on existing mini-splits regardless of who installed them. Most contractors won't.
Ductless explained →Whether it's a repair call, a maintenance visit, or a replacement estimate, every Tru72 job starts with real measurements. $72 diagnostic fee, credited to the repair when you proceed. Mission Ready Plan members pay $39.
Clean. Quality. Comfort.
