What a combustion analysis is
Why Otter-Pro includes it and a basic visual does not.
We measure CO, O2, and temperature rise. That is how a cracked exchanger gets caught — or ruled out — without theater.
No heat is usually an ignitor, flame sensor, pressure switch, or thermostat — not an automatic furnace replacement.
Use this as a field guide to furnace combustion analysis, then book a visit if the house still misbehaves.
We test ignition, flame proving, inducer, and safety switches. Age is a data point, not a diagnosis.
We map furnace combustion analysis to the actual failed part or design limit. Age of the system is a data point, not the diagnosis.
You approve any repair after the findings are written down. Diagnostic visits are a flat $69. New installation estimates are free in-home with a load calculation — not a number invented from square footage on Zillow.
“It’s 15 years old, you need a new system” without readings is a pitch. We show the failed part first.
A company that skips testing on furnace combustion analysis will skip it on the next call too. We would rather lose a job than install the wrong thing.
Related service page on this site: maintenance. The article you are reading is the explanation; that page is how to book the work.
OTTER HVAC is based at 2939 Santos Ln, Walnut Creek. Oakland, Lafayette, and Concord are regular routes, along with the rest of our listed East Bay cities. Hours are 7am–5pm, seven days a week. We do not advertise 24/7 because we do not staff a night shift.
Inland heat (Pleasanton, Livermore, Concord) and marine air (Alameda, Daly City) are different loads. A note written for Oakland is not automatically right for a fog-belt house. We treat them that way.
Category on this guide: Maintenance. Primary search phrase: furnace combustion analysis.
Call (650) 900-0440 or book online. Tell us the city, the symptom in one sentence, and the brand if you know it. If we have a window today, we will say so. If we do not, we will say that too.
Technicians are EPA 608, OSHA, and NATE certified. Public reviews average 5.0 stars across roughly 146 Google and 151 Yelp reviews. That does not replace a test on your unit.
Related service: HVAC Maintenance. Book a $69 diagnostic or a free install estimate. Hours: 7:00am–5:00pm, seven days a week. Shop: 2939 Santos Ln, Walnut Creek, CA 94597.
Related: All HVAC guides · HVAC Maintenance · Pricing and $69 diagnostic · Contact OTTER HVAC
Frequently asked questions
What do you test on a furnace combustion analysis visit?
We test ignition, flame proving, inducer, and safety switches. Age is a data point, not a diagnosis. The visit is a flat $69. Repair work starts only after you approve the written findings.
Will you quote furnace combustion analysis from a photo?
No. We do not price furnace combustion analysis from a driveway photo. $69 diagnostic, then a quote — or a free in-home install estimate if replacement is the honest path.
Do you handle this in Oakland and Lafayette?
Yes. We run Oakland, Lafayette, and the rest of our East Bay list from 2939 Santos Ln, Walnut Creek. Hours are 7am–5pm every day — not 24/7. Call (650) 900-0440.
Explore related pages
References and credentials
- U.S. DOE Energy Saver
- EPA Section 608
- EPA Section 608 refrigerant certification
- U.S. Department of Energy — Energy Saver
Authority sources: U.S. DOE Energy Saver · EPA Section 608