A service visit
Ask about the diagnostic charge, what it covers and whether any of it applies to an approved repair. Diagnosis and repair are separate decisions.
Heating, cooling & home comfort · Orange County
Get help with a system that is not keeping up, plan routine care, or explore a replacement. Start with what you have noticed. You do not need to know the fix.
Need service today? Call (714) 576-4733.
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COST ESTIMATOR
Choose the work and enter its size. Get a starting range without an email address or an existing quote.
Prices checked September 2026. Anything not priced online is confirmed at your visit.
A repair visit, routine care and a replacement estimate start with different questions. Choose yours; no equipment knowledge or contact details needed.
Answer what you know. No name, email or photos needed.
Know what a price covers before deciding whether it fits.
Ask about the diagnostic charge, what it covers and whether any of it applies to an approved repair. Diagnosis and repair are separate decisions.
Compare equipment, sizing assessment, ducts, electrical work, removal, permits and commissioning. An equipment price alone is not an installed system.
Compare the visit schedule, included checks, exclusions and renewal terms. Ask how repairs and priority service are handled separately.
Explore the brief, the choices and the scope behind each project.

A compact outdoor unit anchors a replacement plan that starts inside the house.
Explore the project →
A ductless concept gives a frequently used room a more focused solution.
Explore the project →
An airflow-focused brief looks beyond the thermostat setting.
Explore the project →A good starting point is the part of your home you want to improve.
Plan heating and cooling around the home, not simply the size of the old unit.
Explore this service →Give an office, addition or hard-to-condition room its own comfort plan.
Explore this service →Find out why the system is struggling before deciding what to replace.
Explore this service →A comfortable home begins with a clear description of what is not working. We connect that everyday experience to the assessment, equipment and installation details that belong in the solution.
Listen to the comfort problem first.
Put the complete installation beside the equipment price.
Explain the controls, care and handoff.
Have repair and replacement quotes? Compare the longer-term costs.
Compare your own quotes and annual running-cost estimates over the same period. Keep the comfort questions beside the numbers.
No contact details needed. Your work stays in this browser tab, so download a copy before closing it.
The planner adds your quote to the yearly running and maintenance costs you enter, over 3, 5 or 10 years, so you compare both options the same way.
Prices checked September 2026.
Compare one of our projects with your space and keep the look you like next to your notes.
JPG, PNG or WebP, up to 12 MB. Your photo stays in this browser tab.

“The AC died on the hottest day of the year. I called at 8, Marco was here by 11 and had it running by noon. He showed me the failed part and the price before he touched anything.”
“Two other companies quoted a bigger unit without measuring anything. Stillair did the calculation and put in a smaller heat pump that keeps every room even. Our summer bill dropped.”
“I called about no heat expecting to hear we needed a new furnace. They replaced an igniter, showed us the old one, and told us the furnace has years left.”
A service visit: Ask about the diagnostic charge, what it covers and whether any of it applies to an approved repair. Diagnosis and repair are separate decisions. A replacement: Compare equipment, sizing assessment, ducts, electrical work, removal, permits and commissioning. An equipment price alone is not an installed system. Ongoing care: Compare the visit schedule, included checks, exclusions and renewal terms. Ask how repairs and priority service are handled separately.
We find the fault first. A system under ten years old with one problem usually gets repaired. An old system failing repeatedly gets a repair price and a replacement price so you can compare.
A home-specific load assessment considers more than floor area. Ask how the proposed size was determined and whether the ducts and airflow support it.
Usually, in our mild climate, but it depends on your rates and how you use it. We show you the estimate with its assumptions so you can judge it.
Price the work, keep a planning summary, or send us a note. We reply within one business day.
Find the right service Send us a messageExplore the fit, options and scope for the work you are considering.
Plan heating and cooling around the home, not simply the size of the old unit.
Explore this service →Give an office, addition or hard-to-condition room its own comfort plan.
Explore this service →Find out why the system is struggling before deciding what to replace.
Explore this service →Plan heating and cooling around the home, not simply the size of the old unit.

A replacement project where equipment condition, comfort, operating costs and the home’s requirements need to be considered together.
Keep filters and service access in the maintenance plan. Ask for the manufacturer’s care instructions and a clear explanation of parts and labor coverage.
Give an office, addition or hard-to-condition room its own comfort plan.

A room or zone where extending or changing the central system may not be the best fit.
A ductless system still needs cleaning and maintenance. Discuss filter access, noise and the appearance of line covers before approving locations.
Find out why the system is struggling before deciding what to replace.

A room that never feels right, a strange noise, or a system that keeps needing another repair.
Keep a record of service, filter changes and recurring symptoms. If the same room remains uncomfortable, bring that history to the next assessment.
Different spaces. Different priorities. See how the brief shapes each project.

A compact outdoor unit anchors a replacement plan that starts inside the house.
Explore the project →
A ductless concept gives a frequently used room a more focused solution.
Explore the project →
An airflow-focused brief looks beyond the thermostat setting.
Explore the project →A compact outdoor unit anchors a replacement plan that starts inside the house.

The brief combines summer cooling, winter heating and a clearer ownership plan. The equipment location preserves service access without taking over the garden.
We ran a load calculation on the house, sealed the ducts and checked the panel before choosing the unit.
A ductless concept gives a frequently used room a more focused solution.

The office is in use while the rest of the house is quiet, so that room got its own zone with its own temperature.
One indoor head, a small outdoor unit and a hidden drain line, without touching the rest of the house.
An airflow-focused brief looks beyond the thermostat setting.

The homeowner’s concern is a living room that feels different from the rest of the house. The project begins with the pattern of use and the existing system’s performance.
We measured airflow room by room, repaired two ducts and added a return. No new equipment needed.
Compare the same years and the same assumptions.
The visit to find the fault. You approve any repair before we start it.
HomeGuide cost guide ↗A seasonal tune-up. Repairs and refrigerant are priced separately.
HomeGuide cost guide ↗An installed heat pump. Sizing, ducts and electrical work are confirmed at your visit.
HomeGuide cost guide ↗An installed central air conditioner.
HomeGuide cost guide ↗Furnace and air conditioner replaced together. New ductwork is priced separately.
HomeGuide cost guide ↗Typical installed price ranges. Your written quote confirms the full scope.
Calculate a starting budget →Ask about the diagnostic charge, what it covers and whether any of it applies to an approved repair. Diagnosis and repair are separate decisions.
Compare equipment, sizing assessment, ducts, electrical work, removal, permits and commissioning. An equipment price alone is not an installed system.
Compare the visit schedule, included checks, exclusions and renewal terms. Ask how repairs and priority service are handled separately.
The planner adds your quote to the yearly running and maintenance costs you enter, over 3, 5 or 10 years, so you compare both options the same way.
Ask for quantities, specified products, preparation, exclusions and the process for approving additional work. A lower number is useful only when you understand what changed.
Use the cost estimator for a starting range and the planning tools for scope details. Both create a PDF of your scope and questions. No contact details are required.
Checked September 2026.
A clear path from the first conversation to the completed work.
Separate an active fault, routine care and a replacement goal so the right conversation happens first.
Agree on availability, diagnostic or assessment charges and what the visit includes.
Compare the proposed work and total scope before authorizing it.
Collect commissioning or service records, warranty contacts and maintenance instructions.
A service visit: Ask about the diagnostic charge, what it covers and whether any of it applies to an approved repair. Diagnosis and repair are separate decisions. A replacement: Compare equipment, sizing assessment, ducts, electrical work, removal, permits and commissioning. An equipment price alone is not an installed system. Ongoing care: Compare the visit schedule, included checks, exclusions and renewal terms. Ask how repairs and priority service are handled separately.
We find the fault first. A system under ten years old with one problem usually gets repaired. An old system failing repeatedly gets a repair price and a replacement price so you can compare.
A home-specific load assessment considers more than floor area. Ask how the proposed size was determined and whether the ducts and airflow support it.
Usually, in our mild climate, but it depends on your rates and how you use it. We show you the estimate with its assumptions so you can judge it.
Equipment model numbers, sizing basis, duct and electrical scope, controls, removal, approvals, commissioning and warranty responsibilities. Clarify exclusions before comparing totals.
Only the amounts you enter. Use quotes after any confirmed adjustments, and explain those adjustments when comparing. Inflation, financing, future breakdowns and resale value are excluded.
Same day, seven days a week, when a system has stopped heating or cooling. Call (714) 576-4733. If you smell gas or a carbon monoxide alarm goes off, leave the house and call the utility or 911 first.
A comfortable home begins with a clear description of what is not working. We connect that everyday experience to the assessment, equipment and installation details that belong in the solution.
We believe the proposal should be understandable before the first product is ordered. Good questions about preparation, access and care make the visible result easier to plan.
We serve homeowners in Fullerton, Orange, Irvine, Costa Mesa, Tustin, Anaheim and nearby communities.
Send us a message →“The AC died on the hottest day of the year. I called at 8, Marco was here by 11 and had it running by noon. He showed me the failed part and the price before he touched anything.”
“Two other companies quoted a bigger unit without measuring anything. Stillair did the calculation and put in a smaller heat pump that keeps every room even. Our summer bill dropped.”
“I called about no heat expecting to hear we needed a new furnace. They replaced an igniter, showed us the old one, and told us the furnace has years left.”
What happens with the photos and details you enter on this website.
Estimates and planning answers stay in your browser. A photo you add to the project photo board stays on your device. Reloading or closing the tab clears your work, so download a copy if you want to keep it.
Briefs and planning PDFs include the answers you entered and your questions. They leave out your name, email, message, address and photo. Look them over before you share them.
The contact form opens a message in your own email app. Nothing is sent until you send it.
This website has no analytics or advertising trackers. Links to other websites open their own pages with their own privacy practices.
This is a sample website by Dept5. Stillair Heating & Cooling is a fictional company. Its people, projects and reviews are examples, and the images are illustrations. Prices shown are ranges, not quotes.
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