Two mini split quotes can differ by thousands of dollars and both be honest, because they describe different jobs. The way to compare them is to make each one describe the same rooms, equipment, routes and paperwork, then compare prices. The months before summer, when nobody is sweating through a heat wave, are when there is time to do that.
Mesa Mini Split San Diego installs mini splits across San Diego County and provides written, itemized scopes after a site visit, with the work done by licensed and insured contractors holding the California C-20 (HVAC) license. A printable version of this checklist is on the resources page.
Start with the rooms and the load
Every quote should list the rooms it serves and the capacity of the head in each, and it should say how that capacity was chosen. A Manual J load calculation accounts for windows, insulation, orientation and climate; a guess from square footage does not. The difference shows up inland, where the CEC’s design temperature is 90°F at El Cajon against 82°F at Lindbergh Field. If one quote serves four rooms with four heads and another serves the same rooms with three, ask why; not every room needs its own head, and the sizing guide explains how that is decided.
Equipment: model numbers, not tonnage
“1.5-ton mini split” is not a specification. A comparable quote names the indoor and outdoor model numbers, which let you check the matched combination’s efficiency ratings (SEER2 for cooling and HSPF2 for heating) in AHRI’s certified directory. Near the coast, ask whether the outdoor coil has a factory anticorrosion coating. Single-zone or multi-zone is a design choice with trade-offs, so two quotes that chose differently are not directly comparable until you know why.
Locations, routes and drains
The quote should show where each head goes and where the outdoor unit sits, the approximate line-set length and route, and whether line-hide is included. In the City of San Diego, an outdoor unit in a required side or rear yard sits 4 feet from the property line unless sound attenuation shows it meets the noise limits, so a quote that puts it on a 3-foot side yard should say how it complies; the placement guide covers the rule. Each head also needs a named condensate path, gravity or pump. A quote that is silent on drains has not finished the design.
Electrical and panel work
Look for the circuit, the disconnect and any panel work in writing. If one quote includes a 100-to-200-amp service upgrade and another does not, that alone can explain a large gap: a typical San Diego-area range for that upgrade is about $2,800 to $5,500. Ask whether a load calculation was done on the panel.
Permit, verification and commissioning
A complete quote includes the permit (in the City, the mini split permit starts at $176.57 for the first indoor unit) and any field verification on the compliance form. It should also name the commissioning steps: a nitrogen pressure test, evacuation confirmed with a micron gauge, and a refrigerant charge set to the manufacturer’s specifications. These steps take time, and leaving them out is one way a quote gets cheaper.
The quote comparison checklist
- Rooms served and the capacity of each head, with the load calculation behind it
- Indoor and outdoor model numbers and their efficiency ratings
- Head type and location in each room
- Outdoor unit location, mounting and setback
- Line-set length, route, wall penetrations, stucco patching and line-hide
- Condensate path for each head
- Circuit, disconnect and any panel or service work
- Permit, inspections and field verification
- Commissioning steps
- Exclusions, and any rebate or credit the quote assumes
Reading the totals last
Once the scopes match, the totals mean something, and the installation cost guide shows typical San Diego ranges to check them against. Be wary of any quote that subtracts a federal credit or a utility rebate; the rebates guide explains which programs have closed. For a planning number before you collect quotes, the cost estimator gives one without a phone call, and a call or estimate request books the site visit for a written scope.