Guides
Mini split guides
Answers to the questions that come before an estimate, written for Portland bungalows, ranches, split-levels and condos.
Planning a mini split
Where to start: what a mini split costs in Portland, the permit, how a job runs, and how to add cooling to a house built without it.
- LearnHow do you add air conditioning to an old house in Portland?Adding air conditioning to an old house in Portland: bungalows and foursquares with no ducts upstairs, after the heat dome.
- LearnIs a ductless heat pump the same as a mini split?Two names for one machine, and the few cases where the words point at something different.
- Cost GuideHow much does mini split installation cost in Portland?Typical ranges by job, what moves the number, and the public costs inside it.
- LearnWhat happens during a mini split installation?The mini split installation process, every step from the first call to the city's final inspection, and what you get at the end.
- LearnDo you need a permit for a mini split in Portland?Which permits a new or replacement mini split needs, what they cost, and which office issues them outside Portland.
Single-zone installation
One room, one head: sizing it, placing it, and how it compares with a window unit.
- LearnWhere should a mini split go?Head placement inside, the outdoor unit outside, and the Portland rules and weather that decide both.
- LearnHow do you size a mini split for a Portland room?Mini split sizing in BTUs: design temperatures, the load calculation, and why two rooms the same size can need very different heads.
- Decision GuideWindow AC vs mini split: which is right for your room?A summer stopgap or a permanent system that also heats. What each one does to the room, the bill and the window.
Multi-zone installation
Several rooms on one outdoor unit: counting heads, choosing single or multi-zone, and the circuit it needs.
- LearnHow many mini splits do I need?Count the rooms you close a door on, not the square feet. Then group the heads onto outdoor units.
- LearnWhat are the electrical requirements for a mini split?The circuit, the disconnect, the panel and the permit, and what changes in an older Portland house.
- Decision GuideSingle zone vs multi zone mini split: which should you choose?One outdoor unit per room, or one outdoor unit for several rooms, and why the answer isn't always the cheaper one.
Whole-house systems
Heating the whole house with heads: cold-weather output and how it compares with a ducted heat pump.
- LearnDo mini splits work in cold weather?Portland's winters are mild with sharp exceptions: freezing rain, an east wind and a few nights in the teens.
- Decision GuideMini split vs central heat pump: which fits a Portland house?It comes down to your ducts: whether they exist, where they reach, and what shape they're in.
Baseboard to mini split
Replacing baseboards and wall heaters: the Energy Trust incentive, the electric bill, and rentals.
- LearnHow much will a mini split add to my electric bill?Running costs worked out from PGE, Pacific Power and NW Natural rates, against baseboards and a gas furnace.
- LearnWhat mini split rebates are available in Oregon?What Energy Trust pays, which homes qualify, how state and city programs work, and what's changed for the federal credit.
- Decision GuideIs a mini split a good choice for a rental property?What Oregon law asks of rental cooling, what Energy Trust pays, and how to lay out heads in a house or a fourplex.
Ceiling cassette
Cassettes in the ceiling or heads on the wall: what each needs above and around it.
Repair
When a head drips or trips: drains, pumps and what goes wrong.
Cleaning and maintenance
Filters, coils and wildfire smoke season.