5040 Commercial Circle, Unit C
Concord, CA 94520
(925) 438-8367

Have any feedback for us? We'd love to hear it! Call us at (925) 326-6232 and let us know how we are doing.


Local Reviews

Rated 5.0 out of 5 stars based on 252 customer reviews

Always highly satisfied with your technicians work.

Thank you as always

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Jackie was great!

Another great experience w Certified. Jackie was super helpful and seemed comfortable in spite of the chaos in our home.

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Great service!

All employees at Certified are well trained and do a great job.

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Great service, good customer service, detailed.

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Excellent

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Fine job, great service tech

Certified always helpful, knowledgeable, and prompt.

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Very knowledgeable,professional and well versed.

She was great to talk to.

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Excellent Service!

Mateo was very professional and efficient! He went above and beyond 🙂

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Excellent service technician, reliable company

I thoroughly enjoyed having Diego service our heating system. He was efficient and knowledgeable. He answered my questions and explained everything clearly.

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Great maintenance service

Our heater has been making an annoying rattling sound for a year or two. We were told it wasn’t fixable. But he fixed it! Ahhhh silence.

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Great Service

Diego did a fine job. He was early for the appointment and did a great job.

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Great service

Jackie is very professional and always on time.

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Dependable and efficient.

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Thorough and courteous

Diego was thorough with his inspection and very professional and courteous

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Job Locations

Lee J.

Lee J. Job Checkin

Today certified solar heating and air conditioning are on a 4 day install in Vallejo ca. we will be installing a new 4ton 80% high efficiency furnace, adding a coil and condenser for ac, and replacing the duct work. We will be turning the daycare into its own zone separate from the main house.

Today certified solar heating and air conditioning are on a 4 day install in Vallejo ca. we will be installing a new 4ton 80% high efficiency furnace, adding  a coil and condenser for ac, and replacing the duct work. We will be turning the daycare into its own zone separate from the main house.

Diego C.

Diego C. Job Checkin

Out in Sunnyvale this afternoon performing a furnace maintenance and a/c safety check for the Lopresto residence. After today there system will be more efficient with there scheduled preventative maintenance.

Out in Sunnyvale this afternoon performing a furnace maintenance and a/c safety check for the Lopresto residence. After today there system will be more efficient with there scheduled preventative maintenance.

Jackie G.

Jackie G. Job Checkin

This static pressure is bananas! This is a test that we do , sorta like checking the vitals on our machine! We will be back next week to talk about how to get our unit to a healthy static pressure! Thank you for having us Mrs. Brown!

This static pressure is bananas! This is a test that we do , sorta like checking the vitals on our machine! We will be back next week to talk about how to get our unit to a healthy static pressure! Thank you for having us Mrs. Brown!

Galen  S.

Galen S. Job Checkin

Came back out to Louis’ house to go over heat pump options. Looking into solar options as well.


Galen  S.

Galen S. Job Checkin

Came out to Castro Valley to speak with one of our members about upgrading their central heating systems. We discussed all equipment options available for their home and did a full airflow assessment

Came out to Castro Valley to speak with one of our members about upgrading their central heating systems. We discussed all equipment options available for their home and did a full airflow assessment

Jackie G.

Jackie G. Job Checkin

Today we are finishing this maintenance on an American standard from 1999. The first picture is a blower motor that is leaking oil. The second picture are hot spots in the heat chambers! Preventative maintenance is important to keep these things from happening.

Today we are finishing this maintenance on an American standard from 1999. The first picture is a blower motor that is leaking oil. The second picture are hot spots in the heat chambers! Preventative maintenance is important to keep these things from happening.

Jackie G.

Jackie G. Job Checkin

We’re here working on a 1999 American standard furnace! The first picture is a blower motor that is leaking oil . The second picture is showing us signs that our furnace is getting too hot . Furnace maintenance is important to prevent these kinds of things!

We’re here working on a 1999 American standard furnace! The first picture is a blower motor that is leaking oil . The second picture is showing us signs that our furnace is getting too hot . Furnace maintenance is important to prevent these kinds of things!

Diego C.

Diego C. Job Checkin

In the hills of Moraga, California this afternoon performing a furnace maintenance and a/c safety check for the White residence. There scheduled maintenance helped me bring to there attention that there uv light was out. We are going to come back out and replace it so the whites get complete function out of there uv light stick!

In the hills of Moraga, California this afternoon performing a furnace maintenance and a/c safety check for the White residence. There scheduled maintenance helped me bring to there attention that there uv light was out. We are going to come back out and replace it  so the whites get complete function out of there uv light stick!

Wyatt C.

Wyatt C. Job Checkin

Today we installed a new 2.5 Ton 14.2 Seer Package Unit in Concord, Ca. Glad to help provide a comfortable living space to another happy client!

Today we installed a new 2.5 Ton 14.2 Seer Package Unit in Concord, Ca. Glad to help provide a comfortable living space to another happy client!

Jackie G.

Jackie G. Job Checkin

Just finishing up a furnace Maintenance in concord ca.

Just finishing up a furnace Maintenance in concord ca.

Galen  S.

Galen S. Job Checkin

I came to the Berkeley Hills to speak with Alex about upgrading her heating system. We discussed different technologies and efficiencies and came up with the best plan to take care of her heating issues. Look forward to speaking with her soon and installing a new central furnace.

I came to the Berkeley Hills to speak with Alex about upgrading her heating system. We discussed different technologies and efficiencies and came up with the best plan to take care of her heating issues. Look forward to speaking with her soon and installing a new central furnace.

Diego C.

Diego C. Job Checkin

In Hayward this afternoon performing a furnace maintenance and a/c safety check for the osaze residence. They recently got new attic insulation through us and have noticed a difference tremendously! Both systems were running up to par after today’s scheduled maintenance.

In Hayward this afternoon performing a furnace maintenance and a/c safety check for the osaze residence. They recently got new attic insulation through us and have noticed a difference tremendously! Both systems were running up to par after today’s scheduled maintenance.

Josh K.

Josh K. Job Checkin

Performing a pretty sight of all ductwork in attic, and a beautiful home in Concord California. We always look forward to doing work in this neighborhood.

Performing a pretty sight of all ductwork in attic, and a beautiful home in Concord California. We always look forward to doing work in this neighborhood.

Lee J.

Lee J. Job Checkin

Here in the Walnut Creek area replacing a mini split head under warranty. We had installed 8 mini split heads here last summer. One of the heads in the office had failed, so we came out ASAP to replace it and get the system up and running again

Here in the Walnut Creek area replacing a mini split head under warranty. We had installed 8 mini split heads here last summer. One of the heads in the office had failed, so we came out ASAP to replace it and get the system up and running again

Jackie G.

Jackie G. Job Checkin

Furnace maintenance. This unit is a carrier from 2014. This unit is collecting some dirt and hair from inside home into the blower wheel. It’s important for our blower wheel to be clean and light so the fins scoop more air then dirt into the home!

Furnace maintenance. This unit is a carrier from 2014. This unit is collecting some dirt and hair from inside home into the blower wheel. It’s important for our blower wheel to be clean and light so the fins scoop more air then dirt into the home!